Gastrointestinal tract toxicity represents a serious adverse effect of chemotherapy,leading to reduced quality of life and survival.For instance,irinotecan(CPT-11)usually causes severe gastrointestinal toxicity,with a...Gastrointestinal tract toxicity represents a serious adverse effect of chemotherapy,leading to reduced quality of life and survival.For instance,irinotecan(CPT-11)usually causes severe gastrointestinal toxicity,with a lack of effective therapeutic interventions,making treatment often unsustainable.Therefore,development of an effective and safe therapy is crucial for improving chemotherapy efficacy and the patients’quality of life.In this work,we developed a novel approach involving the helical-shaped cyanobacterium microalgae,Spirulina platensis(SP),to carry the bornyl acetate(BA)-loaded chitosan nanoparticles to enhance drug retention in the small intestine.We demonstrated the protection effect of BA against chemotherapy-induced intestinal injury using an epithelial cell model.In a mouse model,orally administered BA-ChNPs@SP accumulated in the small intestine and attenuated inflammation by reducing dsDNA release and oxidative stress.This was concomitant with the restoration of the intestinal barrier and modulation of the immune microenvironment.This work suggests the promise of the microalgae-carrying nanomedicine strategy for treatment of intestinal diseases,emphasizing its potential in addressing chemotherapy-induced gastrointestinal complications.展开更多
This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a ...This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a general part covering the grand lines and more in-depth views of more recent tannin,lignin,carbohydrate and soy bioadhesives,somemix of the other bio raw materials with soy protein and soy flour and some other differently sourced bioadhesives for wood,this review presents a more in-depth part on starch-based wood adhesives and a more indepth part covering plant protein-based adhesives.It must be kept in mind that the review is focused on completely or almost completely biosourced adhesives,the fashionable adhesives derived from mixes of biosourced materials with synthetic resins having been intentionally excluded.This choice was made as the latter constitute only an intermediate interval,possibly temporary if even for a somewhat long times,towards a final full bioeconomy of scale in this field.This review also focuses on more recent results,mainly obtained in the last 10–20 years,thus on adhesive formulations really innovative and sometimes even non-traditional.In all these fields there is still a lot of possibility of innovation for relevant formulation as this field is still in rapid growth.展开更多
Gatifloxacin eye drops are frequently used in eye infections.However such formulations have a major drawback i.e.short duration of action and usually require 4e6 times installations daily.A chitosan coated niosomal fo...Gatifloxacin eye drops are frequently used in eye infections.However such formulations have a major drawback i.e.short duration of action and usually require 4e6 times installations daily.A chitosan coated niosomal formulation of gatifloxain was purposed to show a longer retention time on eyes and subsequent reduction in dosing frequency.Vesicles were prepared by solvent injection method using cholesterol and Span-60.An extensive optimization of formulation was done using different ratios of cholesterol,Span-60 and drug,revealed NS60-5(cholesterol:span-6050:50 and drug content of 20 mg)to be the optimized niosome formulation.NS60-5 had shown a highest entrapment efficiency of 64.9±0.66%with particle size 213.2±1.5 nm and zeta potential34.7±2.2 mV.Optimized niosomes were also coated with different concentrations of chitosan and evaluated.Permeation studies had revealed that optimized niosomes(86.77±1.31%)had increased the transcorneal permeation of Gatifloxacin more than two fold than simple drug solution(37.19±1.1%).Longer retention potential of the coated niosomes was further verified by fluorescence microscopy.Study revealed that simple dye solution got easily washed out with in 6 h.The uncoated niosomes(NS60-5)showed a longer retention(more than 6 h),which was further enhanced in case of coated niosomes i.e.CNS60-1(more than 12 h).Antimicrobial studies had shown the better efficacy of CNS60-1(zone of inhibition)when compared to marketed formulation.The final chitosan formulation was found to have shown better ocular tolerability as demonstrated by corneal hydration test histopathology investigations.展开更多
Polycarbophil(PCP),a kind of pharmaceutical polymers with superior bioadhesive properties has been widely used in the field of controlled drug delivery systems.It could be used as a highly efficient thickener,bioadhe...Polycarbophil(PCP),a kind of pharmaceutical polymers with superior bioadhesive properties has been widely used in the field of controlled drug delivery systems.It could be used as a highly efficient thickener,bioadhesive agent,suspending aid and emulsion stabilizer when dispersed in water or other polar solvents.These exceptional utilities of the polymers result from their hydrophilic nature.Hydrogen bonding plays an important role in most adhesion behaviours and becomes the main adhesion force.This paper reviews the applications of PCP in pharmacy over the past decades,and clarifies its unique advantages in the bioadhesive formulations.After an introduction discussing its structural characteristics and action mechanism,the focus turned to the description of its available applications in detail with particular emphasis on the ocular,nasal,vagina and oral drug delivery systems.The other less developed formulations are also described,including the buccal and the transdermal delivery systems.展开更多
A high performance composite membrane was prepared under the inspiration of bioadhesion principles for pervaporative dehydration of ethanol.Chitosan(CS)and polyacrylonitrile(PAN)ultrafiltration membranes were used as ...A high performance composite membrane was prepared under the inspiration of bioadhesion principles for pervaporative dehydration of ethanol.Chitosan(CS)and polyacrylonitrile(PAN)ultrafiltration membranes were used as the active layer and the support layer,respectively.Guar gum(GG),a natural bioadhesive,was introduced as the intermediate bonding layer to improve the separation performance and stability of the fabricated CS/GG/PAN composite membranes.The contact angle of the GG layer was just between those of the CS layer and the PAN layer,minimizing the difference of hydrophilicity between the active layer and the support layer.The peeling strength of the composite membrane was significantly enhanced after the introduction of the GG layer.The effects of preparation conditions and operation conditions including GG concentration,operating temperature and ethanol concentration in feed on the pervaporation performance were investigated.The as-fabricated CS/GG/PAN composite membrane showed the optimum performance with a permeation flux of up to804 g·m-2·h-1and a separation factor higher than 1900.Besides,the composite membranes exhibited a desirable long-term operational stability.展开更多
Bioadhesive polymers can serve as surgical sealants with a wide range of potential clinical applications, including augmentation of wound closure and acute induction of hemostasis. Key determinants of sealant efficacy...Bioadhesive polymers can serve as surgical sealants with a wide range of potential clinical applications, including augmentation of wound closure and acute induction of hemostasis. Key determinants of sealant efficacy include the strength and duration of tissue-material adhesion, as well as material biocompatibility. Canonical bioadhesive materials, however, are limited by a tradeoff among performance criteria that is largely governed by the efficiency of tissue-material interactions. In general, increasingly bioreactive materials are endowed with greater bioadhesive potential and protracted residence time, but incite more tissue damage and localized inflammation. One emergent strategy to improve sealant clinical performance is application-specific material design, with the goal of leveraging both local soft tissue surface chemistry and environmental factors to promote adhesive tissue-material interactions. We hypothesize that copolymer systems with equivalent bioreactive group densities (isoreactive) but different amounts/oxidation states of constituent polymers will exhibit differential interactions across soft tissue types. We synthesized an isoreactive family of aldehyde-mediated co-polymers, and subjected these materials to physical (gelation time), mechanical (bulk modulus and adhesion strength), and biological (in-vitro cytotoxicity and in-vivo biocompatibility) assays indicative of sealant performance. Results show that while bioadhesion to a range of soft tissue surfaces (porcine aortic adventitia, renal artery adventitia, renal cortex, and pericardium) varies with isoreactive manipulation, general indicators of material biocompatibility remain constant. Together these findings suggest that isore-active tuning of polymeric systems is a promising strategy to circumvent current challenges in surgical sealant applications.展开更多
Gelatin-based biomaterials have emerged as promising candidates for bioadhesives due to their biodegradability and biocompatibility.However,they often face limitations due to the uncontrollable phase transition of gel...Gelatin-based biomaterials have emerged as promising candidates for bioadhesives due to their biodegradability and biocompatibility.However,they often face limitations due to the uncontrollable phase transition of gelatin,which is dominated by hydrogen bonds between peptide chains.Here,we developed controllable phase transition gelatin-based(CPTG)bioadhesives by regulating the dynamic balance of hydrogen bonds between the peptide chains using 2-hydroxyethylurea(HU)and punicalagin(PA).These CPTG bioadhesives exhibited significant enhancements in adhesion energy and injectability even at 4℃compared to traditional gelatin bioadhesives.The developed bioadhesives could achieve self-reinforcing interfacial adhesion upon contact with moist wound tissues.This effect was attributed to HU diffusion,which disrupted the dynamic balance of hydrogen bonds and therefore induced a localized structural densification.This process was further facilitated by the presence of pyrogallol from PA.Furthermore,the CPTG bioadhesive could modulate the immune microenvironment,offering antibacterial,antioxidant,and immune-adjustable properties,thereby accelerating diabetic wound healing,as confirmed in a diabetic wound rat model.This proposed design strategy is not only crucial for developing controllable phase-transition bioadhesives for diverse applications,but also paves the way for broadening the potential applications of gelatin-based biomaterials.展开更多
The high demand for rapid wound healing has spurred the development of multifunctional and smart bioadhesives with strong bioadhesion,antibacterial effect,real-time sensing,wireless communication,and on-demand treatme...The high demand for rapid wound healing has spurred the development of multifunctional and smart bioadhesives with strong bioadhesion,antibacterial effect,real-time sensing,wireless communication,and on-demand treatment capabilities.Bioadhesives with bio-inspired structures and chemicals have shown unprecedented adhesion strengths,as well as tunable optical,electrical,and bio-dissolvable properties.Accelerated wound healing has been achieved via directly released antibacterial and growth factors,material or drug-induced host immune responses,and delivery of curative cells.Most recently,the integration of biosensing and treatment modules with wireless units in a closed-loop system yielded smart bioadhesives,allowing real-time sensing of the physiological conditions(e.g.,pH,temperature,uric acid,glucose,and cytokine)with iterative feedback for drastically enhanced,stage-specific wound healing by triggering drug delivery and treatment to avoid infection or prolonged inflammation.Despite rapid advances in the burgeoning field,challenges still exist in the design and fabrication of integrated systems,particularly for chronic wounds,presenting significant opportunities for the future development of next-generation smart materials and systems.展开更多
Objective: Pueraria total flavonids(PTF) can treat cardiovascular and cerebrovascular diseases, but it has poor membrane permeability and oral bioavailability. Some excipients, such as carbomer, chitosan, and hydroxyp...Objective: Pueraria total flavonids(PTF) can treat cardiovascular and cerebrovascular diseases, but it has poor membrane permeability and oral bioavailability. Some excipients, such as carbomer, chitosan, and hydroxypropyl methylcellulose, can improve the oral bioavailability. Traditional in vitro evaluation techniques, including the rat intestinal perfusion and cell line models, cannot evaluate PTF absorption and holistic transporters.Methods: This study evaluated excipients' adhesiveness and effect on PTF transport across Caco-2 cell monolayer. cDNA microarrays identified gene expression changes in Caco-2 cells exposed to PTF and PTF with excipients, and revealed the mechanism underlying the effect of excipients on PTF absorption.Results: In vitro adhesion and transport experiments across Caco-2 showed that excipients had higher adhesiveness to gastric mucosa and transport efficiency across Caco-2 cells than PTF alone. The interaction of PTF with excipients significantly changed the expression of some genes, which might influence the absorption rate of PTF.Conclusion: Different bioadhesive polymers can improve intestinal absorption of PTF, which was related to some genes affiliated to the ATP-binding cassette(ABC) and solute carrier transporter(SLC) to some extent.展开更多
Keratoplasty is the gold standard treatment for visual impairment caused by corneal damage.The use of suturing as the bonding method is the source of many complications following keratoplasty.Currently available corne...Keratoplasty is the gold standard treatment for visual impairment caused by corneal damage.The use of suturing as the bonding method is the source of many complications following keratoplasty.Currently available corneal adhesives do not have both adequate adhesive strength and acceptable biocompatibility.Herein,we developed a photocurable bioadhesive hydrogel which was composed of gelatin methacryloyl and oxidized dextran for sutureless keratoplasty.The bioadhesive hydrogel exhibited high light transmittance,resistance to enzymatic degradation and excellent biocompatibility.It also had higher adhesive strength than commercial adhesives(fibrin glue).In a rabbit model of lamellar keratoplasty,donor corneal grafts could be closely bonded to the recipient corneal bed and remained attached for 56 days by using of this in situ photopolymerized bioadhesive hydrogel.The operated cornea maintained transparent and noninflamed.Sutureless keratoplasty using bioadhesive hydrogel allowed rapid graft re-epithelialization,typically within 7 days.In vivo confocal microscopic and histological evaluation of the operated cornea did not show any apparent abnormalities in terms of corneal cells and ultrastructure.Thus,this bioadhesive hydrogel is exhibited to be an appealing alternative to sutures for keratoplasty and other corneal surgeries.展开更多
Effective control of post-extraction hemorrhage and alveolar bone resorption is critical for successful extraction socket treatment,which remains an unmet clinical challenge.Herein,an injectable Tetra-PEG hydrogel tha...Effective control of post-extraction hemorrhage and alveolar bone resorption is critical for successful extraction socket treatment,which remains an unmet clinical challenge.Herein,an injectable Tetra-PEG hydrogel that possesses rapid gelation,firm tissue adhesion,high mechanical strength,suitable degradability,and excellent biocompatibility is developed as a sutureless and coagulation-independent bioadhesive for the management of extraction sockets.Our results demonstrate that the rapid and robust adhesive sealing of the extraction socket by the Tetra-PEG hydrogel can provide reliable protection for the underlying wound and stabilize blood clots to facilitate tissue healing.In vivo experiments using an anticoagulated rat tooth extraction model show that the hydrogel significantly outperformed clinically used cotton and gelatin sponge in hemostatic efficacy,wound closure,alveolar ridge preservation,and in situ alveolar bone regeneration.Histomorphological evaluations reveal the mechanisms for accelerated bone repair through suppressed long-term inflammation,elevated collagen deposition,higher osteoblast activity,and enhanced angiogenesis.Together,our study highlights the clinical potential of the developed injectable Tetra-PEG hydrogel for treating anticoagulant-related post-extraction hemorrhage and improving socket healing.展开更多
Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow an...Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow and/or weak adhesive,poor mechanical strength,low biocompatibility,and poor biodegradability,which largely limit their clinical application in GI perforation repair.In this work,we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive(SS)composed of tetra-armed poly(ethylene glycol)amine(Tetra-PEG-NH2)and tetra-armed poly(ethylene glycol)succinimidyl succinate(Tetra-PEG-SS)for the sutureless repair of GI defects.The SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric models.Importantly,the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue formation.The in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion,suppressed inflammation,and enhanced angiogenesis.Together,our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.展开更多
Postoperative radiotherapy is the standard method for inhibition of breast cancer recurrence and metastasis,whereas radiation resistant and ineluctable skin radiation injury are still key problems encountered in the p...Postoperative radiotherapy is the standard method for inhibition of breast cancer recurrence and metastasis,whereas radiation resistant and ineluctable skin radiation injury are still key problems encountered in the prognosis of breast cancer.Herein,we design an internally implantable biodegradable hydrogel and extracutaneously applicable antioxidant bioadhesive to concurrently prevent postoperative tumor recurrence and radioactive skin injury after adjuvant radiotherapy.The biodegradable silk fibroin/perfluorocarbon hydrogel loading doxorubicin(DOX)formed by consecutive ultrasonication-inducedβ-sheets-crosslinked amphiphilic silk fibroin/perfluorocarbon/DOX nanoemulsion,exhibits continuous release of oxygen in physiological environment to improve hypoxia and sensitivity of radiotherapy,as well as simultaneous release of DOX to finally achieve effective anti-cancer effect.A stretchable bioadhesive is fabricated by copolymerization ofα-thioctic acid and N,N-diacryloyl-L-lysine,and gold nanorods and gallic acid are loaded into the bioadhesive to afford gentle photothermal therapy and antioxidant functions.The near-infrared light-induced controlled release of gallic acid and mild photothermal therapy can efficiently eliminate excess free radicals generated by radiotherapy and promote radioactive wound healing.Ultimately,in vivo animal studies substantiate the efficacy of our methodology,wherein the post-tumor resection administration of hydrogel and concomitant application of an antioxidant bioadhesive patch effectively inhibit tumor recurrence and attenuate the progression of skin radiation damage.展开更多
Due to the nature of non-invasive wound closure,the ability to close different forms of leaks,and the potential to immobilize various devices,bioadhesives are altering clinical practices.As one of the vital factors,bi...Due to the nature of non-invasive wound closure,the ability to close different forms of leaks,and the potential to immobilize various devices,bioadhesives are altering clinical practices.As one of the vital factors,bioadhesives’strength is determined by adhesion and cohesion mechanisms.As well as being essential for adhesion strength,the cohesion mechanism also influences their bulk functions and the way the adhesives can be applied.Although there are many published reports on various adhesion mechanisms,cohesion mechanisms have rarely been addressed.In this review,we have summarized the most used cohesion mechanisms.Furthermore,the relationship of cohesion strategies and adhesion strategies has been discussed,including employing the same functional groups harnessed for adhesion,using combinational approaches,and exploiting different strategies for cohesion mechanism.By providing a comprehensive insight into cohesion strategies,the paper has been integrated to offer a roadmap to facilitate the commercialization of bioadhesives.展开更多
Corneal transplantation is an effective clinical treatment for corneal diseases,which,however,is limited by donor corneas.It is of great clinical value to develop bioadhesive corneal patches with functions of“Transpa...Corneal transplantation is an effective clinical treatment for corneal diseases,which,however,is limited by donor corneas.It is of great clinical value to develop bioadhesive corneal patches with functions of“Transparency”and“Epithelium&Stroma generation”,as well as“Suturelessness”and“Toughness”.To simultaneously meet the“T.E.S.T.”requirements,a light-curable hydrogel is designed based on methacryloylated gelatin(GelMA),Pluronic F127 diacrylate(F127DA)&Aldehyded Pluronic F127(AF127)co-assembled bi-functional micelles and collagen type I(COL I),combined with clinically applied corneal cross-linking(CXL)technology for repairing damaged cornea.The patch formed after 5 min of ultraviolet irradiation possesses transparent,highly tough,and strongly bio-adhesive performance.Multiple cross-linking makes the patch withstand deformation near 600%and exhibit a burst pressure larger than 400 mmHg,significantly higher than normal intraocular pressure(10-21 mmHg).Besides,the slower degradation than GelMA-F127DA&AF127 hydrogel without COL I makes hydrogel patch stable on stromal beds in vivo,supporting the regrowth of corneal epithelium and stroma.The hydrogel patch can replace deep corneal stromal defects and well bio-integrate into the corneal tissue in rabbit models within 4 weeks,showing great potential in surgeries for keratoconus and other corneal diseases by combining with CXL.展开更多
Bioadhesive gels with robust adhesion on wet and irregular tissue surfaces are desirable for clinical applications.Assembly of bioadhesive powders is an effective strategy for obtaining gels that adhere to wet and irr...Bioadhesive gels with robust adhesion on wet and irregular tissue surfaces are desirable for clinical applications.Assembly of bioadhesive powders is an effective strategy for obtaining gels that adhere to wet and irregular tissue surfaces by absorbing interfacial water.However,current bioadhesive powders lack positive biological functions and are prone to postoperative adhesion.Here,we present a powder strategy based on metal-ligand coordination to create a series of bioadhesive polyacrylic acid(PAA)gels.In the gel network,metal ions(M^(n+))are used to coordinate with the carboxy ligands of PAA to form dynamic noncovalent crosslinks.The powders can absorb interfacial water and assemble into gels on wet and irregular tissue surfaces within a few seconds,forming an initial adhesion layer by electrostatic interactions.Furthermore,the polymers can diffuse into the tissue matrix,and metal-ligand coordination is reconstructed to enhance the adhesion.Moreover,with a cationic shield layer,the bioadhesive powders can effectively avoid postoperative adhesion.Importantly,M^(n+) ions endow the gel with customized biological functions.We demonstrate that the hemostatic,antibacterial,peroxidase-like catalytic,and photodetachment abilities of the gels by incorporating different M^(n+) ions.These advantages make the bioadhesive powder a promising platform for diverse tissue repair applications.展开更多
Repairing Achilles tendon has emerged as a long-standing challenge in the orthopaedic surgeries.Although suture is the gold standard for re-attaching and repairing the fractured Achilles tendons in clinical surgeries,...Repairing Achilles tendon has emerged as a long-standing challenge in the orthopaedic surgeries.Although suture is the gold standard for re-attaching and repairing the fractured Achilles tendons in clinical surgeries,it is still subjected to numerous adverse side-effects,including chronic inflammatory,tendon tissue re-rupture,scar formation,and post-surgical peritendinous adhesion.In this work,we develop a class of hydrogel bioadhesives with tailored nanoscale phase separation for Achilles tendon repairing.To address the existing limitations of sutures,our hydrogel bioadhesives encompass three core functionalities:(i)instant and tough adhesion to Achilles tendon tissues,(ii)extraordinary long-term adhesion robustness under wet and dynamic in vivo conditions,and(iii)anti-postsurgical peritendinous adhesion.Combining our hydrogel bioadhesives with sutures,such kind of integrated approach enables a conformable yet robust biointerface with the tendon tissues,and prevents the fibroblast migration and formation of connective tissues,thus facilitating the tendon repairing.The hydrogel bioadhesives reported here open up new opportunities for the repairing of fractured Achilles tendons in diverse and complicated clinical scenarios.展开更多
The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-ben...The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-benefit option on the market due to their lightness and lower cost compared to solid wood.However,the synthetic adhesives used in producing traditional particleboard panels cause serious harm to human health.Developing particleboard panels with fibrous waste and natural adhesives could be a sustainable alternative for these sectors.The work aimed to create particleboards with fibrous wastes from the pseudostem of the banana tree(Musa paradisiaca)and different proportions of the natural adhesive cassava starch-CS in replacement of synthetic adhesive urea-formaldehyde-UF.Five experimental groups were manufactured with banana trees and different percentages of UF and CS adhesives,namely(100UF–0%CS),(50%UF–50%CS),(30%UF–70%CS),(10%UF–90%CS)and(0%UF–100%CS).The particleboards had their physical-mechanical properties determined.The apparent density values did not show significant variation between the assessed treatments.Regarding the water absorption and thickness swelling,the best performances were observed for the panels made without the addition of CS(100%UF).For the mechanical properties of static bending strength and Janka hardness,it was identified that adding up to 50%CS did not interfere with the quality of the panels.These analyses show that the particleboard panels produced with wastes of the banana tree bonded with natural CS adhesivemay be an economically viable and environmentally correct alternative,positively strengthening the development of sustainable strategies.展开更多
Gelatin based adhesives have been used in the last decades in different biomedical applications due to the excellent biocompatibility,easy processability,transparency,non-toxicity,and reasonable mechanical properties ...Gelatin based adhesives have been used in the last decades in different biomedical applications due to the excellent biocompatibility,easy processability,transparency,non-toxicity,and reasonable mechanical properties to mimic the extracellular matrix(ECM).Gelatin adhesives can be easily tuned to gain different viscoelastic and mechanical properties that facilitate its ocular application.We herein grafted glycidyl methacrylate on the gelatin backbone with a simple chemical modification of the precursor,utilizing epoxide ring-opening reactions and visible light-crosslinking.This chemical modification allows the obtaining of an elastic protein-based hydrogel(GELGYM)with excellent biomimetic properties,approaching those of the native tissue.GELGYM can be modulated to be stretched up to 4 times its initial length and withstand high tensile stresses up to 1.95 MPa with compressive strains as high as 80%compared to Gelatin-methacryloyl(GeIMA),the most studied derivative of gelatin used as a bioadhesive.GELGYM is also highly biocompatible and supports cellular adhesion,proliferation,and migration in both 2 and 3-dimensional cell-cultures.These characteristics along with its super adhesion to biological tissues such as cornea,aorta,heart,muscle,kidney,liver,and spleen suggest widespread applications of this hydrogel in many biomedical areas such as transplantation,tissue adhesive,wound dressing,bioprinting,and drug and cell delivery.展开更多
Helicobacter pylori (H. pylori) is one of the most common pathogenic bacterial infections and is found in the stomachs of approximately half of the world’s population. It is the primary known cause of gast...Helicobacter pylori (H. pylori) is one of the most common pathogenic bacterial infections and is found in the stomachs of approximately half of the world’s population. It is the primary known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. However, combined drug therapy as the general treatment in the clinic, the rise of antibiotic-resistant bacteria, adverse reactions and poor patient compliance are major obstacles to the eradication of H. pylori. Oral site-specific drug delivery systems that could increase the longevity of the treatment agent at the target site might improve the therapeutic effect and avoid side effects. Gastroretentive drug delivery systems potentially prolong the gastric retention time and controlled/sustained release of a drug, thereby increasing the concentration of the drug at the application site, potentially improving its bioavailability and reducing the necessary dosage. Recommended gastroretentive drug delivery systems for enhancing local drug delivery include floating systems, bioadhesive systems and expandable systems. In this review, we summarize the important physiological parameters of the gastrointestinal tract that affect the gastric residence time. We then focus on various aspects useful in the development of gastroretentive drug delivery systems, including current trends and the progress of novel forms, especially with respect to their application for the treatment of H. pylori infections.展开更多
基金the National Key Research and Development Program of China(2022YFE0203600,China)NFSC(81925035,82341232)+2 种基金Program of Shanghai Committee of Science and Technology(21ZR1475200,China)Department of Science and Technology of Guangdong Province(High-Level R&D and Innovative Research Institute 2021B0909050003)SciTech Projects of Zhongshan(CXTD2022011,LJ2021001).
文摘Gastrointestinal tract toxicity represents a serious adverse effect of chemotherapy,leading to reduced quality of life and survival.For instance,irinotecan(CPT-11)usually causes severe gastrointestinal toxicity,with a lack of effective therapeutic interventions,making treatment often unsustainable.Therefore,development of an effective and safe therapy is crucial for improving chemotherapy efficacy and the patients’quality of life.In this work,we developed a novel approach involving the helical-shaped cyanobacterium microalgae,Spirulina platensis(SP),to carry the bornyl acetate(BA)-loaded chitosan nanoparticles to enhance drug retention in the small intestine.We demonstrated the protection effect of BA against chemotherapy-induced intestinal injury using an epithelial cell model.In a mouse model,orally administered BA-ChNPs@SP accumulated in the small intestine and attenuated inflammation by reducing dsDNA release and oxidative stress.This was concomitant with the restoration of the intestinal barrier and modulation of the immune microenvironment.This work suggests the promise of the microalgae-carrying nanomedicine strategy for treatment of intestinal diseases,emphasizing its potential in addressing chemotherapy-induced gastrointestinal complications.
文摘This review is composed of three main parts each of which is written by well-known top specialists that have been,in a way or other,also the main participants of the majority of the developments reported.Thus,after a general part covering the grand lines and more in-depth views of more recent tannin,lignin,carbohydrate and soy bioadhesives,somemix of the other bio raw materials with soy protein and soy flour and some other differently sourced bioadhesives for wood,this review presents a more in-depth part on starch-based wood adhesives and a more indepth part covering plant protein-based adhesives.It must be kept in mind that the review is focused on completely or almost completely biosourced adhesives,the fashionable adhesives derived from mixes of biosourced materials with synthetic resins having been intentionally excluded.This choice was made as the latter constitute only an intermediate interval,possibly temporary if even for a somewhat long times,towards a final full bioeconomy of scale in this field.This review also focuses on more recent results,mainly obtained in the last 10–20 years,thus on adhesive formulations really innovative and sometimes even non-traditional.In all these fields there is still a lot of possibility of innovation for relevant formulation as this field is still in rapid growth.
文摘Gatifloxacin eye drops are frequently used in eye infections.However such formulations have a major drawback i.e.short duration of action and usually require 4e6 times installations daily.A chitosan coated niosomal formulation of gatifloxain was purposed to show a longer retention time on eyes and subsequent reduction in dosing frequency.Vesicles were prepared by solvent injection method using cholesterol and Span-60.An extensive optimization of formulation was done using different ratios of cholesterol,Span-60 and drug,revealed NS60-5(cholesterol:span-6050:50 and drug content of 20 mg)to be the optimized niosome formulation.NS60-5 had shown a highest entrapment efficiency of 64.9±0.66%with particle size 213.2±1.5 nm and zeta potential34.7±2.2 mV.Optimized niosomes were also coated with different concentrations of chitosan and evaluated.Permeation studies had revealed that optimized niosomes(86.77±1.31%)had increased the transcorneal permeation of Gatifloxacin more than two fold than simple drug solution(37.19±1.1%).Longer retention potential of the coated niosomes was further verified by fluorescence microscopy.Study revealed that simple dye solution got easily washed out with in 6 h.The uncoated niosomes(NS60-5)showed a longer retention(more than 6 h),which was further enhanced in case of coated niosomes i.e.CNS60-1(more than 12 h).Antimicrobial studies had shown the better efficacy of CNS60-1(zone of inhibition)when compared to marketed formulation.The final chitosan formulation was found to have shown better ocular tolerability as demonstrated by corneal hydration test histopathology investigations.
基金the work was supported by a research group from Shenyang Pharmaceutical University,including the financial support.And get the vigorous help from all the teachers and students of Pharmacy Department.
文摘Polycarbophil(PCP),a kind of pharmaceutical polymers with superior bioadhesive properties has been widely used in the field of controlled drug delivery systems.It could be used as a highly efficient thickener,bioadhesive agent,suspending aid and emulsion stabilizer when dispersed in water or other polar solvents.These exceptional utilities of the polymers result from their hydrophilic nature.Hydrogen bonding plays an important role in most adhesion behaviours and becomes the main adhesion force.This paper reviews the applications of PCP in pharmacy over the past decades,and clarifies its unique advantages in the bioadhesive formulations.After an introduction discussing its structural characteristics and action mechanism,the focus turned to the description of its available applications in detail with particular emphasis on the ocular,nasal,vagina and oral drug delivery systems.The other less developed formulations are also described,including the buccal and the transdermal delivery systems.
基金Supported by the New Century Excellent Talents in University(NCET-10-0623)the National Natural Science Foundation for Distinguished Young Scholars(21125627)+1 种基金the National Basic Research Program of China(2009CB623404)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(Dong Hua University)
文摘A high performance composite membrane was prepared under the inspiration of bioadhesion principles for pervaporative dehydration of ethanol.Chitosan(CS)and polyacrylonitrile(PAN)ultrafiltration membranes were used as the active layer and the support layer,respectively.Guar gum(GG),a natural bioadhesive,was introduced as the intermediate bonding layer to improve the separation performance and stability of the fabricated CS/GG/PAN composite membranes.The contact angle of the GG layer was just between those of the CS layer and the PAN layer,minimizing the difference of hydrophilicity between the active layer and the support layer.The peeling strength of the composite membrane was significantly enhanced after the introduction of the GG layer.The effects of preparation conditions and operation conditions including GG concentration,operating temperature and ethanol concentration in feed on the pervaporation performance were investigated.The as-fabricated CS/GG/PAN composite membrane showed the optimum performance with a permeation flux of up to804 g·m-2·h-1and a separation factor higher than 1900.Besides,the composite membranes exhibited a desirable long-term operational stability.
文摘Bioadhesive polymers can serve as surgical sealants with a wide range of potential clinical applications, including augmentation of wound closure and acute induction of hemostasis. Key determinants of sealant efficacy include the strength and duration of tissue-material adhesion, as well as material biocompatibility. Canonical bioadhesive materials, however, are limited by a tradeoff among performance criteria that is largely governed by the efficiency of tissue-material interactions. In general, increasingly bioreactive materials are endowed with greater bioadhesive potential and protracted residence time, but incite more tissue damage and localized inflammation. One emergent strategy to improve sealant clinical performance is application-specific material design, with the goal of leveraging both local soft tissue surface chemistry and environmental factors to promote adhesive tissue-material interactions. We hypothesize that copolymer systems with equivalent bioreactive group densities (isoreactive) but different amounts/oxidation states of constituent polymers will exhibit differential interactions across soft tissue types. We synthesized an isoreactive family of aldehyde-mediated co-polymers, and subjected these materials to physical (gelation time), mechanical (bulk modulus and adhesion strength), and biological (in-vitro cytotoxicity and in-vivo biocompatibility) assays indicative of sealant performance. Results show that while bioadhesion to a range of soft tissue surfaces (porcine aortic adventitia, renal artery adventitia, renal cortex, and pericardium) varies with isoreactive manipulation, general indicators of material biocompatibility remain constant. Together these findings suggest that isore-active tuning of polymeric systems is a promising strategy to circumvent current challenges in surgical sealant applications.
基金supported by National Key Research and Development Program of China(grant nos.2021YFA1000200 and 2021YFA1000201)National Natural Science Foundation of China(grant nos.12372175,12102010 and 52363019)+1 种基金Tianjin Municipal Science and Technology Plan Project(grant no.24ZYCGSY00650)Tianjin Health Technology Project(grant no.TJWJ2022XK043).
文摘Gelatin-based biomaterials have emerged as promising candidates for bioadhesives due to their biodegradability and biocompatibility.However,they often face limitations due to the uncontrollable phase transition of gelatin,which is dominated by hydrogen bonds between peptide chains.Here,we developed controllable phase transition gelatin-based(CPTG)bioadhesives by regulating the dynamic balance of hydrogen bonds between the peptide chains using 2-hydroxyethylurea(HU)and punicalagin(PA).These CPTG bioadhesives exhibited significant enhancements in adhesion energy and injectability even at 4℃compared to traditional gelatin bioadhesives.The developed bioadhesives could achieve self-reinforcing interfacial adhesion upon contact with moist wound tissues.This effect was attributed to HU diffusion,which disrupted the dynamic balance of hydrogen bonds and therefore induced a localized structural densification.This process was further facilitated by the presence of pyrogallol from PA.Furthermore,the CPTG bioadhesive could modulate the immune microenvironment,offering antibacterial,antioxidant,and immune-adjustable properties,thereby accelerating diabetic wound healing,as confirmed in a diabetic wound rat model.This proposed design strategy is not only crucial for developing controllable phase-transition bioadhesives for diverse applications,but also paves the way for broadening the potential applications of gelatin-based biomaterials.
基金supported by the National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health under Award No.R21EB030140the National Heart,Lung,and Blood Institute of the National Institutes of Health under Award Number R61HL154215,the National Science Foundation(NSF)(Grant No.ECCS-1933072)Penn State University.Y.L.would like to acknowledge the support of the Natural Science Foundation of China under Grant 61825102,U21A20460.
文摘The high demand for rapid wound healing has spurred the development of multifunctional and smart bioadhesives with strong bioadhesion,antibacterial effect,real-time sensing,wireless communication,and on-demand treatment capabilities.Bioadhesives with bio-inspired structures and chemicals have shown unprecedented adhesion strengths,as well as tunable optical,electrical,and bio-dissolvable properties.Accelerated wound healing has been achieved via directly released antibacterial and growth factors,material or drug-induced host immune responses,and delivery of curative cells.Most recently,the integration of biosensing and treatment modules with wireless units in a closed-loop system yielded smart bioadhesives,allowing real-time sensing of the physiological conditions(e.g.,pH,temperature,uric acid,glucose,and cytokine)with iterative feedback for drastically enhanced,stage-specific wound healing by triggering drug delivery and treatment to avoid infection or prolonged inflammation.Despite rapid advances in the burgeoning field,challenges still exist in the design and fabrication of integrated systems,particularly for chronic wounds,presenting significant opportunities for the future development of next-generation smart materials and systems.
基金supported by the national natural science fund projects(No.81274094)
文摘Objective: Pueraria total flavonids(PTF) can treat cardiovascular and cerebrovascular diseases, but it has poor membrane permeability and oral bioavailability. Some excipients, such as carbomer, chitosan, and hydroxypropyl methylcellulose, can improve the oral bioavailability. Traditional in vitro evaluation techniques, including the rat intestinal perfusion and cell line models, cannot evaluate PTF absorption and holistic transporters.Methods: This study evaluated excipients' adhesiveness and effect on PTF transport across Caco-2 cell monolayer. cDNA microarrays identified gene expression changes in Caco-2 cells exposed to PTF and PTF with excipients, and revealed the mechanism underlying the effect of excipients on PTF absorption.Results: In vitro adhesion and transport experiments across Caco-2 showed that excipients had higher adhesiveness to gastric mucosa and transport efficiency across Caco-2 cells than PTF alone. The interaction of PTF with excipients significantly changed the expression of some genes, which might influence the absorption rate of PTF.Conclusion: Different bioadhesive polymers can improve intestinal absorption of PTF, which was related to some genes affiliated to the ATP-binding cassette(ABC) and solute carrier transporter(SLC) to some extent.
基金supported by National Natural Science Foundation of China(81870633)Guangdong Province Key Field R&D Program(2020B1111150002).
文摘Keratoplasty is the gold standard treatment for visual impairment caused by corneal damage.The use of suturing as the bonding method is the source of many complications following keratoplasty.Currently available corneal adhesives do not have both adequate adhesive strength and acceptable biocompatibility.Herein,we developed a photocurable bioadhesive hydrogel which was composed of gelatin methacryloyl and oxidized dextran for sutureless keratoplasty.The bioadhesive hydrogel exhibited high light transmittance,resistance to enzymatic degradation and excellent biocompatibility.It also had higher adhesive strength than commercial adhesives(fibrin glue).In a rabbit model of lamellar keratoplasty,donor corneal grafts could be closely bonded to the recipient corneal bed and remained attached for 56 days by using of this in situ photopolymerized bioadhesive hydrogel.The operated cornea maintained transparent and noninflamed.Sutureless keratoplasty using bioadhesive hydrogel allowed rapid graft re-epithelialization,typically within 7 days.In vivo confocal microscopic and histological evaluation of the operated cornea did not show any apparent abnormalities in terms of corneal cells and ultrastructure.Thus,this bioadhesive hydrogel is exhibited to be an appealing alternative to sutures for keratoplasty and other corneal surgeries.
基金support for the work from the Ministry of Science and Technology of China (2020YFA0908900)National Natural Science Foundation of China (21935011 and 21725403)+2 种基金Shenzhen Science and Technology Innovation Commission (KQTD20200820113012029,JCYJ20190814114605162,and JCYJ20220818100601003)Guangdong Basic and Applied Basic Research Foundation (2022A1515110321)Guangdong Provincial Key Laboratory of Advanced Biomaterials (2022B1212010003).
文摘Effective control of post-extraction hemorrhage and alveolar bone resorption is critical for successful extraction socket treatment,which remains an unmet clinical challenge.Herein,an injectable Tetra-PEG hydrogel that possesses rapid gelation,firm tissue adhesion,high mechanical strength,suitable degradability,and excellent biocompatibility is developed as a sutureless and coagulation-independent bioadhesive for the management of extraction sockets.Our results demonstrate that the rapid and robust adhesive sealing of the extraction socket by the Tetra-PEG hydrogel can provide reliable protection for the underlying wound and stabilize blood clots to facilitate tissue healing.In vivo experiments using an anticoagulated rat tooth extraction model show that the hydrogel significantly outperformed clinically used cotton and gelatin sponge in hemostatic efficacy,wound closure,alveolar ridge preservation,and in situ alveolar bone regeneration.Histomorphological evaluations reveal the mechanisms for accelerated bone repair through suppressed long-term inflammation,elevated collagen deposition,higher osteoblast activity,and enhanced angiogenesis.Together,our study highlights the clinical potential of the developed injectable Tetra-PEG hydrogel for treating anticoagulant-related post-extraction hemorrhage and improving socket healing.
基金gratefully acknowledge the support for the work from Ministry of Science and Technology of China(2020YFA0908900)National Natural Science Foundation of China(21935011 and 21725403)+2 种基金Shenzhen Science and Technology Innovation Commission(KQTD20200820113012029 and JCYJ20220818100601003)Guangdong Basic and Applied Basic Research Foundation(2022A1515110321,2019A1515110511)Guangdong Provincial Key Laboratory of Advanced Biomaterials(2022B1212010003).
文摘Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation management.However,several concerns remain for the existing bioadhesives including slow and/or weak adhesive,poor mechanical strength,low biocompatibility,and poor biodegradability,which largely limit their clinical application in GI perforation repair.In this work,we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive(SS)composed of tetra-armed poly(ethylene glycol)amine(Tetra-PEG-NH2)and tetra-armed poly(ethylene glycol)succinimidyl succinate(Tetra-PEG-SS)for the sutureless repair of GI defects.The SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric models.Importantly,the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue formation.The in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion,suppressed inflammation,and enhanced angiogenesis.Together,our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.
基金support for this work from the National Natural Science Foundation of China(Grant No.52233008,51733006,32301120)the CAMS Innovation Fund for Medical Sciences(2021-I2M-1-042,2021-I2M-1-060)the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2022-RC350-06).
文摘Postoperative radiotherapy is the standard method for inhibition of breast cancer recurrence and metastasis,whereas radiation resistant and ineluctable skin radiation injury are still key problems encountered in the prognosis of breast cancer.Herein,we design an internally implantable biodegradable hydrogel and extracutaneously applicable antioxidant bioadhesive to concurrently prevent postoperative tumor recurrence and radioactive skin injury after adjuvant radiotherapy.The biodegradable silk fibroin/perfluorocarbon hydrogel loading doxorubicin(DOX)formed by consecutive ultrasonication-inducedβ-sheets-crosslinked amphiphilic silk fibroin/perfluorocarbon/DOX nanoemulsion,exhibits continuous release of oxygen in physiological environment to improve hypoxia and sensitivity of radiotherapy,as well as simultaneous release of DOX to finally achieve effective anti-cancer effect.A stretchable bioadhesive is fabricated by copolymerization ofα-thioctic acid and N,N-diacryloyl-L-lysine,and gold nanorods and gallic acid are loaded into the bioadhesive to afford gentle photothermal therapy and antioxidant functions.The near-infrared light-induced controlled release of gallic acid and mild photothermal therapy can efficiently eliminate excess free radicals generated by radiotherapy and promote radioactive wound healing.Ultimately,in vivo animal studies substantiate the efficacy of our methodology,wherein the post-tumor resection administration of hydrogel and concomitant application of an antioxidant bioadhesive patch effectively inhibit tumor recurrence and attenuate the progression of skin radiation damage.
基金The authors would like to acknowledge the Science Foundation Ireland(SFI)and the European Regional Development Fund(Grant Number 13/RC/2073_P2)for financial assistanceYB is supported by funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 713690.
文摘Due to the nature of non-invasive wound closure,the ability to close different forms of leaks,and the potential to immobilize various devices,bioadhesives are altering clinical practices.As one of the vital factors,bioadhesives’strength is determined by adhesion and cohesion mechanisms.As well as being essential for adhesion strength,the cohesion mechanism also influences their bulk functions and the way the adhesives can be applied.Although there are many published reports on various adhesion mechanisms,cohesion mechanisms have rarely been addressed.In this review,we have summarized the most used cohesion mechanisms.Furthermore,the relationship of cohesion strategies and adhesion strategies has been discussed,including employing the same functional groups harnessed for adhesion,using combinational approaches,and exploiting different strategies for cohesion mechanism.By providing a comprehensive insight into cohesion strategies,the paper has been integrated to offer a roadmap to facilitate the commercialization of bioadhesives.
基金This work was supported by the Shanghai Rising-Star Program(Grants No.21QA1401500)Clinical Research Plan of SHDC(Grants No.SHDC2020CR1043B).
文摘Corneal transplantation is an effective clinical treatment for corneal diseases,which,however,is limited by donor corneas.It is of great clinical value to develop bioadhesive corneal patches with functions of“Transparency”and“Epithelium&Stroma generation”,as well as“Suturelessness”and“Toughness”.To simultaneously meet the“T.E.S.T.”requirements,a light-curable hydrogel is designed based on methacryloylated gelatin(GelMA),Pluronic F127 diacrylate(F127DA)&Aldehyded Pluronic F127(AF127)co-assembled bi-functional micelles and collagen type I(COL I),combined with clinically applied corneal cross-linking(CXL)technology for repairing damaged cornea.The patch formed after 5 min of ultraviolet irradiation possesses transparent,highly tough,and strongly bio-adhesive performance.Multiple cross-linking makes the patch withstand deformation near 600%and exhibit a burst pressure larger than 400 mmHg,significantly higher than normal intraocular pressure(10-21 mmHg).Besides,the slower degradation than GelMA-F127DA&AF127 hydrogel without COL I makes hydrogel patch stable on stromal beds in vivo,supporting the regrowth of corneal epithelium and stroma.The hydrogel patch can replace deep corneal stromal defects and well bio-integrate into the corneal tissue in rabbit models within 4 weeks,showing great potential in surgeries for keratoconus and other corneal diseases by combining with CXL.
基金funding support by the National Natural Science Foundation of China(22072014)the Fundamental Research Funds for the Central Universities(ZYGX2019J119)+3 种基金Chengdu Science and Technology Bureau(2021-GH02-00105-HZ)Shenzhen Science and Technology Program(JCYJ20210324142210027)the Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province(2021ZYD0046)Sichuan Outstanding Young Scholars Foundation(21JCQN0235)。
文摘Bioadhesive gels with robust adhesion on wet and irregular tissue surfaces are desirable for clinical applications.Assembly of bioadhesive powders is an effective strategy for obtaining gels that adhere to wet and irregular tissue surfaces by absorbing interfacial water.However,current bioadhesive powders lack positive biological functions and are prone to postoperative adhesion.Here,we present a powder strategy based on metal-ligand coordination to create a series of bioadhesive polyacrylic acid(PAA)gels.In the gel network,metal ions(M^(n+))are used to coordinate with the carboxy ligands of PAA to form dynamic noncovalent crosslinks.The powders can absorb interfacial water and assemble into gels on wet and irregular tissue surfaces within a few seconds,forming an initial adhesion layer by electrostatic interactions.Furthermore,the polymers can diffuse into the tissue matrix,and metal-ligand coordination is reconstructed to enhance the adhesion.Moreover,with a cationic shield layer,the bioadhesive powders can effectively avoid postoperative adhesion.Importantly,M^(n+) ions endow the gel with customized biological functions.We demonstrate that the hemostatic,antibacterial,peroxidase-like catalytic,and photodetachment abilities of the gels by incorporating different M^(n+) ions.These advantages make the bioadhesive powder a promising platform for diverse tissue repair applications.
基金support by Natural Science Foundation of Guangdong Province(Nos.2022A1515010152 and 2021A1515110735)the Basic Research Program of Shenzhen(Nos.JCYJ20210324105211032 and GJHZ20210705141809030)+1 种基金the Scientific Research Platforms and Projects of University of Guangdong Provincial Education Office(No.2022ZDZX3019)supported in part by the Science,Technology,and Innovation Commission of Shenzhen Municipality(No.ZDSYS20200811143601004).
文摘Repairing Achilles tendon has emerged as a long-standing challenge in the orthopaedic surgeries.Although suture is the gold standard for re-attaching and repairing the fractured Achilles tendons in clinical surgeries,it is still subjected to numerous adverse side-effects,including chronic inflammatory,tendon tissue re-rupture,scar formation,and post-surgical peritendinous adhesion.In this work,we develop a class of hydrogel bioadhesives with tailored nanoscale phase separation for Achilles tendon repairing.To address the existing limitations of sutures,our hydrogel bioadhesives encompass three core functionalities:(i)instant and tough adhesion to Achilles tendon tissues,(ii)extraordinary long-term adhesion robustness under wet and dynamic in vivo conditions,and(iii)anti-postsurgical peritendinous adhesion.Combining our hydrogel bioadhesives with sutures,such kind of integrated approach enables a conformable yet robust biointerface with the tendon tissues,and prevents the fibroblast migration and formation of connective tissues,thus facilitating the tendon repairing.The hydrogel bioadhesives reported here open up new opportunities for the repairing of fractured Achilles tendons in diverse and complicated clinical scenarios.
基金financed by“Conselho Nacional de Desenvolvimento Cientifico e Tecnologico”(CNPq)and“Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior”(CAPES)-Finance Code 001.
文摘The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-benefit option on the market due to their lightness and lower cost compared to solid wood.However,the synthetic adhesives used in producing traditional particleboard panels cause serious harm to human health.Developing particleboard panels with fibrous waste and natural adhesives could be a sustainable alternative for these sectors.The work aimed to create particleboards with fibrous wastes from the pseudostem of the banana tree(Musa paradisiaca)and different proportions of the natural adhesive cassava starch-CS in replacement of synthetic adhesive urea-formaldehyde-UF.Five experimental groups were manufactured with banana trees and different percentages of UF and CS adhesives,namely(100UF–0%CS),(50%UF–50%CS),(30%UF–70%CS),(10%UF–90%CS)and(0%UF–100%CS).The particleboards had their physical-mechanical properties determined.The apparent density values did not show significant variation between the assessed treatments.Regarding the water absorption and thickness swelling,the best performances were observed for the panels made without the addition of CS(100%UF).For the mechanical properties of static bending strength and Janka hardness,it was identified that adding up to 50%CS did not interfere with the quality of the panels.These analyses show that the particleboard panels produced with wastes of the banana tree bonded with natural CS adhesivemay be an economically viable and environmentally correct alternative,positively strengthening the development of sustainable strategies.
基金the Boston-KPro research fund and NIH/NEI P30EY003790(Core-PA)R.S.was supported in part by the K99 grant from NIH award no.K99 EY030553+3 种基金the Center for Nanoscale Systems(CNS),Harvard University,a member of the National Nanotechnology Coordinated Infrastructure Network(NNCI)the National Science Foundation under NSF award no.1541959.F.R-O and D.A-M were supported by the research project ICI19/00006funded by Instituto de Salud CarlosⅢand co-funded by European Union(ERDF/ESF,"A way to make Europe"/"Investing in your future")F.R-O additionally acknowledges funding from Plan Andaluz de Investigaci´on,Desarrollo e Innovaci´on(PAIDI2020)Fellowship supported by Consejería de Economía,Conocimiento,Empresas y Universidad,Junta de Andalucía co-funded by Fondo Social Europeo de Andalucía 2014-2020.
文摘Gelatin based adhesives have been used in the last decades in different biomedical applications due to the excellent biocompatibility,easy processability,transparency,non-toxicity,and reasonable mechanical properties to mimic the extracellular matrix(ECM).Gelatin adhesives can be easily tuned to gain different viscoelastic and mechanical properties that facilitate its ocular application.We herein grafted glycidyl methacrylate on the gelatin backbone with a simple chemical modification of the precursor,utilizing epoxide ring-opening reactions and visible light-crosslinking.This chemical modification allows the obtaining of an elastic protein-based hydrogel(GELGYM)with excellent biomimetic properties,approaching those of the native tissue.GELGYM can be modulated to be stretched up to 4 times its initial length and withstand high tensile stresses up to 1.95 MPa with compressive strains as high as 80%compared to Gelatin-methacryloyl(GeIMA),the most studied derivative of gelatin used as a bioadhesive.GELGYM is also highly biocompatible and supports cellular adhesion,proliferation,and migration in both 2 and 3-dimensional cell-cultures.These characteristics along with its super adhesion to biological tissues such as cornea,aorta,heart,muscle,kidney,liver,and spleen suggest widespread applications of this hydrogel in many biomedical areas such as transplantation,tissue adhesive,wound dressing,bioprinting,and drug and cell delivery.
文摘Helicobacter pylori (H. pylori) is one of the most common pathogenic bacterial infections and is found in the stomachs of approximately half of the world’s population. It is the primary known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. However, combined drug therapy as the general treatment in the clinic, the rise of antibiotic-resistant bacteria, adverse reactions and poor patient compliance are major obstacles to the eradication of H. pylori. Oral site-specific drug delivery systems that could increase the longevity of the treatment agent at the target site might improve the therapeutic effect and avoid side effects. Gastroretentive drug delivery systems potentially prolong the gastric retention time and controlled/sustained release of a drug, thereby increasing the concentration of the drug at the application site, potentially improving its bioavailability and reducing the necessary dosage. Recommended gastroretentive drug delivery systems for enhancing local drug delivery include floating systems, bioadhesive systems and expandable systems. In this review, we summarize the important physiological parameters of the gastrointestinal tract that affect the gastric residence time. We then focus on various aspects useful in the development of gastroretentive drug delivery systems, including current trends and the progress of novel forms, especially with respect to their application for the treatment of H. pylori infections.
