Fabrication of biocompatible core-shell microcapsules in a controllable and scalable manner remains an important but challenging task.Here,we develop a one-step microfluidic approach for the highthroughput production ...Fabrication of biocompatible core-shell microcapsules in a controllable and scalable manner remains an important but challenging task.Here,we develop a one-step microfluidic approach for the highthroughput production of biocompatible microcapsules,which utilizes single emulsions as templates and controls the precipitation of biocompatible polymer at the water/oil interface.The facile method enables the loading of various oils in the core and the enhancement of polymer shell strength by polyelectrolyte coating.The resulting microcapsules have the advantages of controllability,scalability,biocompatibility,high encapsulation efficiency and high loading capacity.The core-shell microcapsules are ideal delivery vehicles for programmable active release and various controlled release mechanisms are demonstrated,including burst release by vigorous shaking,pH-triggered release for targeted intestinal release and sustained release of perfume over a long period of time.The utility of our technique paves the way for practical applications of core-shell microcapsules.展开更多
The purpose of this study was to design and prepare a biocompatible microemulsion of Andrographis paniculata(BMAP) containing both fat-soluble and water-soluble constituents. We determined the contents of active const...The purpose of this study was to design and prepare a biocompatible microemulsion of Andrographis paniculata(BMAP) containing both fat-soluble and water-soluble constituents. We determined the contents of active constituents of BMAP and evaluated its bioavailability. The biocompatible microemulsion(BM), containing lecithin and bile salts, was optimized in the present study, showing a good physical stability. The mean droplet size was 19.12 nm, and the average polydispersity index(PDI) was 0.153. The contents of andrographolide and dehydroandrographolide in BMAP, as determined by high performance liquid chromatography(HPLC), were higher than that in ethanol extraction. The pharmacokinetic results of BMAP showed that the AUC0-7 and AUC0→∞ values of BMAP were 2.267 and 27.156 μg·m L-1·h 1, respectively, and were about 1.41-fold and 6.30-fold greater than that of ethanol extraction, respectively. These results demonstrated that the bioavailability of and rographolide extracted by BMAP was significantly higher than that extracted by ethanol. In conclusion, the BMAP preparation displayed ann improved dose form for future clinical applications.展开更多
A wide variety of different types of microorganisms are known to produce intracellular energy and carbon storage products, which have been generally described as being poly (β-hydroxybutyrate), PHB, but which are, mo...A wide variety of different types of microorganisms are known to produce intracellular energy and carbon storage products, which have been generally described as being poly (β-hydroxybutyrate), PHB, but which are, more often than not, copolymers containing different alkyl groups at the β-position. Hence, PHB belongs to the family ofpoly (β-hydroxyalkanoastes), PHA, all of which are usually formed as intracellular inclusions in bacteria under unbalanced growth conditions. Recently, it became of industrial interest to evaluate these PHA polyesters as natural biodegradable and biocompatible plastics for a wide range of possible applications, such as surgical sutures or packaging containers. For industrial applications, the controlled incorporation of repeating units with different chain lengths into a series of copolymers is desirable in order to produce polyesters with a range of material properties because physical and chemical characteristics depend strongly on the polymer composition. Such 'tailor-made' copolymers can be produced under controlled growth conditions in that, if a defined mixture of substrates for a certain type of microorganisms is supplied, a well defined and reproducible copolymer is formed.展开更多
Many phytochemicals show promise in cancer prevention and treatment, but their low aqueous solubility, poor stability, unfavorable bioavailability, and low target specificity make administering them at therapeutic dos...Many phytochemicals show promise in cancer prevention and treatment, but their low aqueous solubility, poor stability, unfavorable bioavailability, and low target specificity make administering them at therapeutic doses unrealistic. This is particularly true for(-)-epigallocatechin gallate, curcumin, quercetin, resveratrol, and genistein. There is an increasing interest in developing novel delivery strategies for these natural products. Liposomes, micelles, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and poly(lactide-co-glycolide) nanoparticles are biocompatible and biodegradable nanoparticles. Those nanoparticles can increase the stability and solubility of phytochemicals, exhibit a sustained release property, enhance their absorption and bioavailability, protect them from premature enzymatic degradation or metabolism, prolong their circulation time, improve their target specificity to cancer cells or tumors via passive or targeted delivery, lower toxicity or side-effects to normal cells or tissues through preventing them from prematurely interacting with the biological environment, and enhance anti-cancer activities. Nanotechnology opens a door for developing phytochemical-loaded nanoparticles for prevention and treatment of cancer.展开更多
Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables.Ink printing is desirable for e-textile development using a simple and i...Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables.Ink printing is desirable for e-textile development using a simple and inexpensive process.However,fabricating high-performance atop textiles with good dispersity,stability,biocompatibility,and wearability for high-resolution,large-scale manufacturing,and practical applications has remained challenging.Here,waterbased multi-walled carbon nanotubes(MWCNTs)-decorated liquid metal(LM)inks are proposed with carbonaceous gallium–indium micro-nanostructure.With the assistance of biopolymers,the sodium alginate-encapsulated LM droplets contain high carboxyl groups which non-covalently crosslink with silk sericin-mediated MWCNTs.E-textile can be prepared subsequently via printing technique and natural waterproof triboelectric coating,enabling good flexibility,hydrophilicity,breathability,wearability,biocompatibility,conductivity,stability,and excellent versatility,without any artificial chemicals.The obtained e-textile can be used in various applications with designable patterns and circuits.Multi-sensing applications of recognizing complex human motions,breathing,phonation,and pressure distribution are demonstrated with repeatable and reliable signals.Self-powered and energy-harvesting capabilities are also presented by driving electronic devices and lighting LEDs.As proof of concept,this work provides new opportunities in a scalable and sustainable way to develop novel wearable electronics and smart clothing for future commercial applications.展开更多
Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is report...Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is reported.Microfluidic technology is utilized to emulsify the inner aqueous phase containing the shell polymer into monodisperse drops in the outer oil phase.As the cosolvent in the inner aqueous phase diffuses into the outer oil phase,the solubility of the shell polymer decreases,which eventually precipitates.Since the shell polymer,shellac,contains both hydrophilic and hydrophobic groups,it tends to wet both the inner aqueous phase and the outer oil phase,thus forming a solid shell at the periphery of the drop.We show that the diffusion rate of hydrophilic molecules encapsulated in the water core decreases as their molecular weight increases and the property of the microcapsules could further be modified by polyelectrolyte multilayer coating.These microcapsules are fabricated using FDA-approved polymer and non-toxic solvents and are of great use in drugs,cosmetics and foods.展开更多
Due to its unique properties such as high hardness, light transmittance, thermal conductance, chemical stability and corrosion resistance, diamond has drawn tremendous attention in last two decades. These specific pro...Due to its unique properties such as high hardness, light transmittance, thermal conductance, chemical stability and corrosion resistance, diamond has drawn tremendous attention in last two decades. These specific properties made diamond film a promising material for cutting tools, microwave windows, heat sinks for electronic devices and diamond electrodes. However, the diamond film with grain sizes at microscale usually exhibits high surface roughness and hinders its applications in the microelectro mechanical system (MEMS) and biological field because it is difficult to be polished by mechanical and chemical methods. With the development of the chemical vapor deposition, the nanocrystalline diamond (NCD) film has been fabricated and found new applications. The grain size of NCD film is in the range of 10 to 100 nm, which inherits the properties of the diamond and possesses the unique properties of the nanoscale materials, and the morphology of the NCD film is granular or needle-like structure. The microwave plasma chemical vapor deposition (MPCVD) has been regarded as the most promising method to deposit NCD film at low temperature. Compared to the hot filament CVD, MPCVD can grow high quality NCD film avoiding of the contamination from the filament materials. The MPCVD technique has high plasma density to activate carbonaceous compound and grow NCD film in high growth rate and low substrate temperature. The unique properties of NCD film, such as the superior electrical, mechanical and biological properties facilitate their application in various fields. The biological application, especially as a biocompatible coating, mainly includes the joint replacement implants and protective coatings and the ophthalmological prosthesis.展开更多
The soft magnetic materials have potential applications in the field of bioengineering as carriers for targeted drug delivery. The magnetic properties, particle size after coating, Curie temperature and its biocompati...The soft magnetic materials have potential applications in the field of bioengineering as carriers for targeted drug delivery. The magnetic properties, particle size after coating, Curie temperature and its biocompatibility are important parameters for the synthesis of materials. In the present communication cobalt ferrite nanoparticles have been synthesized using co-precipitation method and coated with sodium alginate. The X-ray diffraction and infrared spectroscopic measurements have been used to confirm the ferrite structure formation and coating of the samples with alginate. The SEM micrographs have been used to confirm the particle size which is found to be 45 nm before coating and 78 nm after coating. The saturation magnetization obtained using the hysteresis data for the uncoated cobalt ferrite sample is 19.8 emu/gm while for the coated sample it reduces to 10.2 emu/gm. The AC susceptibility measurements indicate SP structure for the uncoated samples with Curie temperature less than 100℃. The thermo gravimetric measurements have been used to estimate the amount of alginate coating on the sample and it has been correlated with retention of magnetic properties after coating. The value of saturation magnetization reduces after coating due to mass reduction of magnetic material in the sample in accordance with the TGA measurements.展开更多
Here,we present a novel bioorthogonal platform that enables precise positioning of attached moieties in close proximity,thereby facilitating the discovery and optimization of biocompatible reactions.Using this platfor...Here,we present a novel bioorthogonal platform that enables precise positioning of attached moieties in close proximity,thereby facilitating the discovery and optimization of biocompatible reactions.Using this platform,we achieve a Horner-Wadsworth-Emmons(HWE)reaction under physiological conditions,generating a fluorophore in situ with a yield of up to 93%.This proximity platform should facilitate the discovery of various types of biocompatible reactions,making it a versatile tool for biomedical applica-tions.展开更多
Polylactic acid (PLA) was successfully covalently grafted onto multi-walled carbon nanotubes (MWCNT) by microwave-assisted polymerization of lactide monomers. The final products MWCNT-g-PLA were characterized with Fou...Polylactic acid (PLA) was successfully covalently grafted onto multi-walled carbon nanotubes (MWCNT) by microwave-assisted polymerization of lactide monomers. The final products MWCNT-g-PLA were characterized with Fourier-transform IR (FTIR), Raman spectroscopy, thermogravimetric analyses (TGA) and transmission electron microscopy (TEM). The results indicated PLA chain was covalently attached to the MWCNT. The grafted PLA was uniformly coated on the surface of MWCNT with a layer thickness of 2 ~ 6 nm. The grafted PLA content could be controlled by microwave irradiation time and the concentrations of reactant. The product with 60.5% grafted PLA content can be synthesized in one hour.展开更多
A multifunctional nanoparticle based on carboxymethyl cellulose was developed. Folate group was attached to nanoparticle for specific recognition of cancerous cells and 5FU was encapsulated for delivering cytotoxicity...A multifunctional nanoparticle based on carboxymethyl cellulose was developed. Folate group was attached to nanoparticle for specific recognition of cancerous cells and 5FU was encapsulated for delivering cytotoxicity. The whole system was able to track by the semiconductor quantum dots that were attached to the nanoparticle. The multifunctional nanoparticle was characterized by UV-VIS spectra, PL spectra, FTIR, TEM, SEM etc and was targeted to human breast cancer cell, MCF7. The biocompatibility of nanoparticle without drug and cytotoxicity rendered by nanoparticle with drug was studied with MCF7 and L929 cell lines. The epifluorescent images suggest that the folate-conjugated nanoparticles were more internalized by folate receptor positive cell line, MCF7 than the noncancerous L929 cells.展开更多
The chemical reactivity of novel stable triazene 3 toward some nucleophilic and electrophilic reagents was investigated. Traizene 3 was used as a key precursor for the synthesis of some novel important heterocyclic co...The chemical reactivity of novel stable triazene 3 toward some nucleophilic and electrophilic reagents was investigated. Traizene 3 was used as a key precursor for the synthesis of some novel important heterocyclic compounds such as Pyrazole, Isoxazole, Dihydropyrimidine, Tetrahydro-pyridine derivatives with expected antimicrobial activity. The synthesized compounds were obtained in good yields. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1H-NMR and Ms spectral data.展开更多
We describe a new method for transparent and conductive films based on carbon nanotubes and bovine serum albumin composite development. Films are deposited from an aqueous solution of carbon nanotubes/bovine serum alb...We describe a new method for transparent and conductive films based on carbon nanotubes and bovine serum albumin composite development. Films are deposited from an aqueous solution of carbon nanotubes/bovine serum albumin by drop-coating and rod-coating methods. Sheet resistances of as-prepared films vary from 200 Ohm/sq with 50% transmittance to 30 KOhm/sq with 90% transmittance. The maximum sdc/sop ration found in this work is 2.27, which gives a DC conductivity of 4.55 × 104 S·m-1. Atomic force microscopy and Raman spectroscopy studies of the films show that the process of film formation produces neither structural nor chemical changes in the nanotubes. Possibility of using these films for cell culturing is tested on human embryonic fibroblast cell line. Therefore, it is first time ever in literature, when proposed a method, allowing fabricating at the same time transparent, high-conductive and biocompatible CNT films.展开更多
In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous em...In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous emulsion-solvent diffusion methodology was used to produce drug-loaded PLGA nanoparticles without any purification or solvent evaporation requirements.Formulation parameters,such as lactide/glycolide ratio,polymer concentration,solvent/non solvent ratio and non solvent phase,as well as the non ionic tensioactive P188 co-precipitation composition were systematically explored.The optimized formulation(mean size:145 nm,surface charge:-13 m V) was employed to encapsulate various amounts of NSAIDs in a simple and scalable manner.The drug release was characterized in vitro by a complete release for 48 h.These results encourage upcoming preliminary steps for in vivo experiments of prosthesis surface functionalization.展开更多
As the most abundant biopolymer on the earth,cellulose has recently gained significant attention in the development of antibacterial biomaterials.Biodegradability,renewability,strong mechanical properties,tunable aspe...As the most abundant biopolymer on the earth,cellulose has recently gained significant attention in the development of antibacterial biomaterials.Biodegradability,renewability,strong mechanical properties,tunable aspect ratio,and low density offer tremendous possibilities for the use of cellulose in various fields.Owing to the high number of reactive groups(i.e.,hydroxyl groups)on the cellulose surface,it can be readily functionalized with various functional groups,such as aldehydes,carboxylic acids,and amines,leading to diverse properties.In addition,the ease of surface modification of cellulose expands the range of compounds which can be grafted onto its structure,such as proteins,polymers,metal nanoparticles,and antibiotics.There are many studies in which cellulose nano-/microfibrils and nanocrystals are used as a support for antibacterial agents.However,little is known about the relationship between cellulose chemical surface modification and its antibacterial activity or biocompatibility.In this study,we have summarized various techniques for surface modifications of cellulose nanostructures and its derivatives along with their antibacterial and biocompatibility behavior to develop non-leaching and durable antibacterial materials.Despite the high effectiveness of surface-modified cellulosic antibacterial materials,more studies on their mechanism of action,the relationship between their properties and their effectivity,and more in vivo studies are required.展开更多
Mg and its alloys are drawing huge attention since the last two decades as a viable option for temporary implants applications.A commendable progress has already been made in the development of these alloys.The biodeg...Mg and its alloys are drawing huge attention since the last two decades as a viable option for temporary implants applications.A commendable progress has already been made in the development of these alloys.The biodegradable nature of Mg,appreciable biocompatibility of elemental Mg,and its close resemblance to natural bone in terms of density and elastic modulus make them highly preferable option amongst other available alternatives in this field.This review article presents an overview covering the recent advancements made in the field of Mg-based biodegradable implants for orthopaedic implant applications.The paper focuses on alloy development and fabrication techniques,the state of the art of important Mg-based alloy systems in terms of their mechanical properties,in-vitro and in-vivo degradation behaviour and cytotoxicity.Further,the paper reviews the current progress achieved in the clinical transition of Mg-based alloys for orthopaedic fixtures.The review also includes the degradation mechanisms of the alloys in physiological environment and highlights the mismatch existing between the rate of bone healing and alloy degradation due to rapid corrosion of the alloys in such environment,which has still restricted their widespread application.Finally,the surface coating techniques available for the alloys as an effective way to reduce the degradation rate are reviewed,followed by a discussion on the future research prospects.展开更多
Carbon nanotube(CNT)composite materials are very attractive for use in neural tissue engineering and biosensor coatings.CNT scaffolds are excellent mimics of extracellular matrix due to their hydrophilicity,viscosity,...Carbon nanotube(CNT)composite materials are very attractive for use in neural tissue engineering and biosensor coatings.CNT scaffolds are excellent mimics of extracellular matrix due to their hydrophilicity,viscosity,and biocompatibility.CNTs can also impart conductivity to other insulating materials improve mechanical stability guide neuronal cell behavior and trigger axon regeneration.The performance of chitosan(CS)/polyethylene glycol(PEG)composite scaffolds could be optimized by introducing multi-walled CNTs(MWCNTs).CS/PEG/CNT composite scaffolds with CNT content of 1%,3%,and 5%(1%=0.01 g/mL)were prepared by freeze-drying.Their physical and chemical properties and biocompatibility were evaluated.Scanning electron microscopy(SEM)showed that the composite scaffolds had a highly connected porous structure.Transmission electron microscope(TEM)and Raman spectroscopy proved that the CNTs were well dispersed in the CS/PEG matrix and combined with the CS/PEG nanofiber bundles.MWCNTs enhanced the elastic modulus of the scaffold.The porosity of the scaffolds ranged from 83%to 96%.They reached a stable water swelling state within 24 h,and swelling decreased with increasing MWCNT concentration.The electrical conductivity and cell adhesion rate of the scaffolds increased with increasing MWCNT content.Immunofluorescence showed that rat pheochromocytoma(PC12)cells grown in the scaffolds had characteristics similar to nerve cells.We measured changes in the expression of nerve cell markers by quantitative real-time polymerase chain reaction(qRT-PCR),and found that PC12 cells cultured in the scaffolds expressed growth-associated protein 43(GAP43),nerve growth factor receptor(NGFR),and class IIIβ-tubulin(TUBB3)proteins.Preliminary research showed that the prepared CS/PEG/CNT scaffold has good biocompatibility and can be further applied to neural tissue engineering research.展开更多
Monodispersed Fe3O4/polypyrrole （PPy） hollow particles were synthesized via controllable in-situ deposition and polymerization techniques using poly（styrene-co-acrylic） （PSA） latex as template. Field-dependent m...Monodispersed Fe3O4/polypyrrole （PPy） hollow particles were synthesized via controllable in-situ deposition and polymerization techniques using poly（styrene-co-acrylic） （PSA） latex as template. Field-dependent magnetization plot illustrates that the capsules are superparamagnetic at 300 K. FTIR spectrum confirms that the myoglobin （Mb） molecule adsorbed on the surface of Fe3O4/PPy hollow particle essentially retains its native structure. Furthermore, direct electrochemistry of Mb can be realized on Fe3O4/PPy capsules modified pyrolytic graphite disk electrode, which indicates that the magnetic conductive polymer capsules can promote the electron transfer of protein.展开更多
基金supported by the National Natural Science Foundation of China (Nos.21878258 and 11704331)"theFundamental Research Funds for the Central Universities" (No. 2018QNA4046)+2 种基金the Youth Funds of the State Key Laboratory of Fluid Power and Mechatronic Systems (Zhejiang University)supported by the National Science Foundation (No. DMR-1310266)the Harvard Materials Research Science and Engineering Center (No.DMR-1420570)
文摘Fabrication of biocompatible core-shell microcapsules in a controllable and scalable manner remains an important but challenging task.Here,we develop a one-step microfluidic approach for the highthroughput production of biocompatible microcapsules,which utilizes single emulsions as templates and controls the precipitation of biocompatible polymer at the water/oil interface.The facile method enables the loading of various oils in the core and the enhancement of polymer shell strength by polyelectrolyte coating.The resulting microcapsules have the advantages of controllability,scalability,biocompatibility,high encapsulation efficiency and high loading capacity.The core-shell microcapsules are ideal delivery vehicles for programmable active release and various controlled release mechanisms are demonstrated,including burst release by vigorous shaking,pH-triggered release for targeted intestinal release and sustained release of perfume over a long period of time.The utility of our technique paves the way for practical applications of core-shell microcapsules.
基金supported by the National Nature Science Foundation of China(No.81102815)New Teacher Fund for Doctor Station,the Ministry of Education of China(No.20110013120017)
文摘The purpose of this study was to design and prepare a biocompatible microemulsion of Andrographis paniculata(BMAP) containing both fat-soluble and water-soluble constituents. We determined the contents of active constituents of BMAP and evaluated its bioavailability. The biocompatible microemulsion(BM), containing lecithin and bile salts, was optimized in the present study, showing a good physical stability. The mean droplet size was 19.12 nm, and the average polydispersity index(PDI) was 0.153. The contents of andrographolide and dehydroandrographolide in BMAP, as determined by high performance liquid chromatography(HPLC), were higher than that in ethanol extraction. The pharmacokinetic results of BMAP showed that the AUC0-7 and AUC0→∞ values of BMAP were 2.267 and 27.156 μg·m L-1·h 1, respectively, and were about 1.41-fold and 6.30-fold greater than that of ethanol extraction, respectively. These results demonstrated that the bioavailability of and rographolide extracted by BMAP was significantly higher than that extracted by ethanol. In conclusion, the BMAP preparation displayed ann improved dose form for future clinical applications.
文摘A wide variety of different types of microorganisms are known to produce intracellular energy and carbon storage products, which have been generally described as being poly (β-hydroxybutyrate), PHB, but which are, more often than not, copolymers containing different alkyl groups at the β-position. Hence, PHB belongs to the family ofpoly (β-hydroxyalkanoastes), PHA, all of which are usually formed as intracellular inclusions in bacteria under unbalanced growth conditions. Recently, it became of industrial interest to evaluate these PHA polyesters as natural biodegradable and biocompatible plastics for a wide range of possible applications, such as surgical sutures or packaging containers. For industrial applications, the controlled incorporation of repeating units with different chain lengths into a series of copolymers is desirable in order to produce polyesters with a range of material properties because physical and chemical characteristics depend strongly on the polymer composition. Such 'tailor-made' copolymers can be produced under controlled growth conditions in that, if a defined mixture of substrates for a certain type of microorganisms is supplied, a well defined and reproducible copolymer is formed.
基金supported by grant from the National Center for Complementary&Integrative Health(Nos.R15AT007013 and R15AT008733)
文摘Many phytochemicals show promise in cancer prevention and treatment, but their low aqueous solubility, poor stability, unfavorable bioavailability, and low target specificity make administering them at therapeutic doses unrealistic. This is particularly true for(-)-epigallocatechin gallate, curcumin, quercetin, resveratrol, and genistein. There is an increasing interest in developing novel delivery strategies for these natural products. Liposomes, micelles, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and poly(lactide-co-glycolide) nanoparticles are biocompatible and biodegradable nanoparticles. Those nanoparticles can increase the stability and solubility of phytochemicals, exhibit a sustained release property, enhance their absorption and bioavailability, protect them from premature enzymatic degradation or metabolism, prolong their circulation time, improve their target specificity to cancer cells or tumors via passive or targeted delivery, lower toxicity or side-effects to normal cells or tissues through preventing them from prematurely interacting with the biological environment, and enhance anti-cancer activities. Nanotechnology opens a door for developing phytochemical-loaded nanoparticles for prevention and treatment of cancer.
基金funded by The Hong Kong Polytechnic University(Project No.1-WZ1Y,1-YXAK,1-W21C).
文摘Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables.Ink printing is desirable for e-textile development using a simple and inexpensive process.However,fabricating high-performance atop textiles with good dispersity,stability,biocompatibility,and wearability for high-resolution,large-scale manufacturing,and practical applications has remained challenging.Here,waterbased multi-walled carbon nanotubes(MWCNTs)-decorated liquid metal(LM)inks are proposed with carbonaceous gallium–indium micro-nanostructure.With the assistance of biopolymers,the sodium alginate-encapsulated LM droplets contain high carboxyl groups which non-covalently crosslink with silk sericin-mediated MWCNTs.E-textile can be prepared subsequently via printing technique and natural waterproof triboelectric coating,enabling good flexibility,hydrophilicity,breathability,wearability,biocompatibility,conductivity,stability,and excellent versatility,without any artificial chemicals.The obtained e-textile can be used in various applications with designable patterns and circuits.Multi-sensing applications of recognizing complex human motions,breathing,phonation,and pressure distribution are demonstrated with repeatable and reliable signals.Self-powered and energy-harvesting capabilities are also presented by driving electronic devices and lighting LEDs.As proof of concept,this work provides new opportunities in a scalable and sustainable way to develop novel wearable electronics and smart clothing for future commercial applications.
基金the Youth Founds of the State Key Laboratory of Fluid Power and Mechatronic Systems(Zhejiang University)“Thousand Talents Program” for Distinguished Young Scholars+2 种基金C.-X.Zhao acknowledges financial support from Australian Research Council through the award of a 2014 ARC Future Fellowship(No.FT140100726)supported by the National Science Foundation of U.S.A.(No.DMR-1310266)the Harvard Materials Research Science and Engineering Center(No.DMR-1420570)
文摘Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is reported.Microfluidic technology is utilized to emulsify the inner aqueous phase containing the shell polymer into monodisperse drops in the outer oil phase.As the cosolvent in the inner aqueous phase diffuses into the outer oil phase,the solubility of the shell polymer decreases,which eventually precipitates.Since the shell polymer,shellac,contains both hydrophilic and hydrophobic groups,it tends to wet both the inner aqueous phase and the outer oil phase,thus forming a solid shell at the periphery of the drop.We show that the diffusion rate of hydrophilic molecules encapsulated in the water core decreases as their molecular weight increases and the property of the microcapsules could further be modified by polyelectrolyte multilayer coating.These microcapsules are fabricated using FDA-approved polymer and non-toxic solvents and are of great use in drugs,cosmetics and foods.
文摘Due to its unique properties such as high hardness, light transmittance, thermal conductance, chemical stability and corrosion resistance, diamond has drawn tremendous attention in last two decades. These specific properties made diamond film a promising material for cutting tools, microwave windows, heat sinks for electronic devices and diamond electrodes. However, the diamond film with grain sizes at microscale usually exhibits high surface roughness and hinders its applications in the microelectro mechanical system (MEMS) and biological field because it is difficult to be polished by mechanical and chemical methods. With the development of the chemical vapor deposition, the nanocrystalline diamond (NCD) film has been fabricated and found new applications. The grain size of NCD film is in the range of 10 to 100 nm, which inherits the properties of the diamond and possesses the unique properties of the nanoscale materials, and the morphology of the NCD film is granular or needle-like structure. The microwave plasma chemical vapor deposition (MPCVD) has been regarded as the most promising method to deposit NCD film at low temperature. Compared to the hot filament CVD, MPCVD can grow high quality NCD film avoiding of the contamination from the filament materials. The MPCVD technique has high plasma density to activate carbonaceous compound and grow NCD film in high growth rate and low substrate temperature. The unique properties of NCD film, such as the superior electrical, mechanical and biological properties facilitate their application in various fields. The biological application, especially as a biocompatible coating, mainly includes the joint replacement implants and protective coatings and the ophthalmological prosthesis.
文摘The soft magnetic materials have potential applications in the field of bioengineering as carriers for targeted drug delivery. The magnetic properties, particle size after coating, Curie temperature and its biocompatibility are important parameters for the synthesis of materials. In the present communication cobalt ferrite nanoparticles have been synthesized using co-precipitation method and coated with sodium alginate. The X-ray diffraction and infrared spectroscopic measurements have been used to confirm the ferrite structure formation and coating of the samples with alginate. The SEM micrographs have been used to confirm the particle size which is found to be 45 nm before coating and 78 nm after coating. The saturation magnetization obtained using the hysteresis data for the uncoated cobalt ferrite sample is 19.8 emu/gm while for the coated sample it reduces to 10.2 emu/gm. The AC susceptibility measurements indicate SP structure for the uncoated samples with Curie temperature less than 100℃. The thermo gravimetric measurements have been used to estimate the amount of alginate coating on the sample and it has been correlated with retention of magnetic properties after coating. The value of saturation magnetization reduces after coating due to mass reduction of magnetic material in the sample in accordance with the TGA measurements.
基金supported by the National Natural Science Foundation of China(Nos.21977075,22271200)the National Key R&D Program of China(Nos.2022YFC2009902,2022YFC2009900)+1 种基金the Science and Technology Plan Project of Sichuan Province(No.2023YFS0121)the 1·3·5 Project for Disciplines of Excellence at West China Hospital(No.ZYYC23003),Sichuan University。
文摘Here,we present a novel bioorthogonal platform that enables precise positioning of attached moieties in close proximity,thereby facilitating the discovery and optimization of biocompatible reactions.Using this platform,we achieve a Horner-Wadsworth-Emmons(HWE)reaction under physiological conditions,generating a fluorophore in situ with a yield of up to 93%.This proximity platform should facilitate the discovery of various types of biocompatible reactions,making it a versatile tool for biomedical applica-tions.
文摘Polylactic acid (PLA) was successfully covalently grafted onto multi-walled carbon nanotubes (MWCNT) by microwave-assisted polymerization of lactide monomers. The final products MWCNT-g-PLA were characterized with Fourier-transform IR (FTIR), Raman spectroscopy, thermogravimetric analyses (TGA) and transmission electron microscopy (TEM). The results indicated PLA chain was covalently attached to the MWCNT. The grafted PLA was uniformly coated on the surface of MWCNT with a layer thickness of 2 ~ 6 nm. The grafted PLA content could be controlled by microwave irradiation time and the concentrations of reactant. The product with 60.5% grafted PLA content can be synthesized in one hour.
文摘A multifunctional nanoparticle based on carboxymethyl cellulose was developed. Folate group was attached to nanoparticle for specific recognition of cancerous cells and 5FU was encapsulated for delivering cytotoxicity. The whole system was able to track by the semiconductor quantum dots that were attached to the nanoparticle. The multifunctional nanoparticle was characterized by UV-VIS spectra, PL spectra, FTIR, TEM, SEM etc and was targeted to human breast cancer cell, MCF7. The biocompatibility of nanoparticle without drug and cytotoxicity rendered by nanoparticle with drug was studied with MCF7 and L929 cell lines. The epifluorescent images suggest that the folate-conjugated nanoparticles were more internalized by folate receptor positive cell line, MCF7 than the noncancerous L929 cells.
文摘The chemical reactivity of novel stable triazene 3 toward some nucleophilic and electrophilic reagents was investigated. Traizene 3 was used as a key precursor for the synthesis of some novel important heterocyclic compounds such as Pyrazole, Isoxazole, Dihydropyrimidine, Tetrahydro-pyridine derivatives with expected antimicrobial activity. The synthesized compounds were obtained in good yields. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1H-NMR and Ms spectral data.
文摘We describe a new method for transparent and conductive films based on carbon nanotubes and bovine serum albumin composite development. Films are deposited from an aqueous solution of carbon nanotubes/bovine serum albumin by drop-coating and rod-coating methods. Sheet resistances of as-prepared films vary from 200 Ohm/sq with 50% transmittance to 30 KOhm/sq with 90% transmittance. The maximum sdc/sop ration found in this work is 2.27, which gives a DC conductivity of 4.55 × 104 S·m-1. Atomic force microscopy and Raman spectroscopy studies of the films show that the process of film formation produces neither structural nor chemical changes in the nanotubes. Possibility of using these films for cell culturing is tested on human embryonic fibroblast cell line. Therefore, it is first time ever in literature, when proposed a method, allowing fabricating at the same time transparent, high-conductive and biocompatible CNT films.
基金financially supported by the European Erasmus program
文摘In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous emulsion-solvent diffusion methodology was used to produce drug-loaded PLGA nanoparticles without any purification or solvent evaporation requirements.Formulation parameters,such as lactide/glycolide ratio,polymer concentration,solvent/non solvent ratio and non solvent phase,as well as the non ionic tensioactive P188 co-precipitation composition were systematically explored.The optimized formulation(mean size:145 nm,surface charge:-13 m V) was employed to encapsulate various amounts of NSAIDs in a simple and scalable manner.The drug release was characterized in vitro by a complete release for 48 h.These results encourage upcoming preliminary steps for in vivo experiments of prosthesis surface functionalization.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)an NSERC-FPinnovations CRD grant for supporting this researchMcGill University for a MEDA fellowship.
文摘As the most abundant biopolymer on the earth,cellulose has recently gained significant attention in the development of antibacterial biomaterials.Biodegradability,renewability,strong mechanical properties,tunable aspect ratio,and low density offer tremendous possibilities for the use of cellulose in various fields.Owing to the high number of reactive groups(i.e.,hydroxyl groups)on the cellulose surface,it can be readily functionalized with various functional groups,such as aldehydes,carboxylic acids,and amines,leading to diverse properties.In addition,the ease of surface modification of cellulose expands the range of compounds which can be grafted onto its structure,such as proteins,polymers,metal nanoparticles,and antibiotics.There are many studies in which cellulose nano-/microfibrils and nanocrystals are used as a support for antibacterial agents.However,little is known about the relationship between cellulose chemical surface modification and its antibacterial activity or biocompatibility.In this study,we have summarized various techniques for surface modifications of cellulose nanostructures and its derivatives along with their antibacterial and biocompatibility behavior to develop non-leaching and durable antibacterial materials.Despite the high effectiveness of surface-modified cellulosic antibacterial materials,more studies on their mechanism of action,the relationship between their properties and their effectivity,and more in vivo studies are required.
文摘Mg and its alloys are drawing huge attention since the last two decades as a viable option for temporary implants applications.A commendable progress has already been made in the development of these alloys.The biodegradable nature of Mg,appreciable biocompatibility of elemental Mg,and its close resemblance to natural bone in terms of density and elastic modulus make them highly preferable option amongst other available alternatives in this field.This review article presents an overview covering the recent advancements made in the field of Mg-based biodegradable implants for orthopaedic implant applications.The paper focuses on alloy development and fabrication techniques,the state of the art of important Mg-based alloy systems in terms of their mechanical properties,in-vitro and in-vivo degradation behaviour and cytotoxicity.Further,the paper reviews the current progress achieved in the clinical transition of Mg-based alloys for orthopaedic fixtures.The review also includes the degradation mechanisms of the alloys in physiological environment and highlights the mismatch existing between the rate of bone healing and alloy degradation due to rapid corrosion of the alloys in such environment,which has still restricted their widespread application.Finally,the surface coating techniques available for the alloys as an effective way to reduce the degradation rate are reviewed,followed by a discussion on the future research prospects.
基金This study was supported by the National Natural Science Foundation of China(Nos.51975400 and 62031022)the Shanxi Provincial Key Medical Scientific Research Project(No.2020XM06),China.
文摘Carbon nanotube(CNT)composite materials are very attractive for use in neural tissue engineering and biosensor coatings.CNT scaffolds are excellent mimics of extracellular matrix due to their hydrophilicity,viscosity,and biocompatibility.CNTs can also impart conductivity to other insulating materials improve mechanical stability guide neuronal cell behavior and trigger axon regeneration.The performance of chitosan(CS)/polyethylene glycol(PEG)composite scaffolds could be optimized by introducing multi-walled CNTs(MWCNTs).CS/PEG/CNT composite scaffolds with CNT content of 1%,3%,and 5%(1%=0.01 g/mL)were prepared by freeze-drying.Their physical and chemical properties and biocompatibility were evaluated.Scanning electron microscopy(SEM)showed that the composite scaffolds had a highly connected porous structure.Transmission electron microscope(TEM)and Raman spectroscopy proved that the CNTs were well dispersed in the CS/PEG matrix and combined with the CS/PEG nanofiber bundles.MWCNTs enhanced the elastic modulus of the scaffold.The porosity of the scaffolds ranged from 83%to 96%.They reached a stable water swelling state within 24 h,and swelling decreased with increasing MWCNT concentration.The electrical conductivity and cell adhesion rate of the scaffolds increased with increasing MWCNT content.Immunofluorescence showed that rat pheochromocytoma(PC12)cells grown in the scaffolds had characteristics similar to nerve cells.We measured changes in the expression of nerve cell markers by quantitative real-time polymerase chain reaction(qRT-PCR),and found that PC12 cells cultured in the scaffolds expressed growth-associated protein 43(GAP43),nerve growth factor receptor(NGFR),and class IIIβ-tubulin(TUBB3)proteins.Preliminary research showed that the prepared CS/PEG/CNT scaffold has good biocompatibility and can be further applied to neural tissue engineering research.
基金the National Natural Science Foundation of China (No.10672154)National Science Fund of Ministry of Education of Anhui Province (No.2005KJ135).
文摘Monodispersed Fe3O4/polypyrrole （PPy） hollow particles were synthesized via controllable in-situ deposition and polymerization techniques using poly（styrene-co-acrylic） （PSA） latex as template. Field-dependent magnetization plot illustrates that the capsules are superparamagnetic at 300 K. FTIR spectrum confirms that the myoglobin （Mb） molecule adsorbed on the surface of Fe3O4/PPy hollow particle essentially retains its native structure. Furthermore, direct electrochemistry of Mb can be realized on Fe3O4/PPy capsules modified pyrolytic graphite disk electrode, which indicates that the magnetic conductive polymer capsules can promote the electron transfer of protein.
