Polydopamine(PD)coating,one of the simplest and most versatile surface functionalization method faces challenges in terms of stability and reactivity.In this study,we propose an in situ dynamic reassembly approach to ...Polydopamine(PD)coating,one of the simplest and most versatile surface functionalization method faces challenges in terms of stability and reactivity.In this study,we propose an in situ dynamic reassembly approach to address these challenges.By immersing a pre-deposited PD coating in a strong alkaline solution containing poly(allylamine)hydrochloride(PAH),the dissociated PD oligomers undergo covalent crosslinking in situ,leading to the formation of a reconstructed PDPA coating enriched with stable amino groups through thorough crosslinking.The PDPA coating demonstrates superior chemical and mechanical stability compared to PD,while enhancing multifunctional properties and offering improved surface functional modification potential.The PDPA coating holds promise in materials science,biomedical engineering,and nanotechnology,enabling versatile surface modification and functionalization in extreme conditions.展开更多
Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-...Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-sterilizable polypropylene-based membrane for face masks to address challenges associated with infection transmission prevention.The membrane,created using 3D printing,underwent functionalization with zinc oxide(ZnO)and polydopamine(PDA)-TEMPO to achieve broad-spectrum light absorption and facilitate self-sterilization through photocatalytic and photothermal effects upon light exposure.The hydrophobic surface(water contact angle:133±2°)minimized moisture accumulation,and the membrane exhibited robust mechanical properties,including shear strength(1.25±0.5kPa)and peel resistance strength(112.8±11.2kPa).The evaluation demonstrated stability in airflow(0-500cm^(3)/s)and excellent aerosol filtration efficiency(94.8±0.6%)for particles(PM 0.3,PM 2.5,PM 10),comparable to commercial masks.The membrane showed antibacterial efficacy over five uses in a simulated respiratory environment.Safety assessments confirmed biocompatibility through cytocompatibility and skin irritation assays.In conclusion,this membrane offers efficient filtration and photo-triggered sterilization,presenting a promising solution for next-generation face masks to address concerns related to reuse,disposal,and infection control.展开更多
The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing...The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing the mussel-inspired Polydopamine(PDA)to introduce a strong chemical-physical bonding between titanium and PEEK.The enhanced Fiber-Metal Laminate(FML)exhibits a significant 48.82%enhancement in Interlaminar Shear Strength(ILSS).In addition,it alters the failure mode of the FML from single metal-resin interlaminar delamination to a multi-mechanism,including debonding,delamination of different composite layers,leading to a 28.57%improvement in maximum displacement.展开更多
In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF...In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF).COF@CB@MPDA possessed good water dispersibility and was synthesized by the selfpolymerization of dopamine under alkaline conditions in the presence of the COF,CB and CF.The high surface area COF enhanced the adsorption of CF,whilst CB gave the composites high electrical conductivity to improve the sensitivity of the proposed COF@CB@MPDA/glassy carbon electrode(GCE)sensor.The specific recognition of CF by COF@CB@MPDA involved hydrogen bonding and van der Waals interactions.Under optimized conditions,the sensor showed a good linear relationship with CF concentration over the range of 5.0×10^(–7)and 1.0×10^(–4)mol/L,with a limit of detection(LOD)of 9.53×10^(–8)mol/L.Further,the developed sensor exhibited high selectivity,repeatability and stability for CF detection in milk and milk powders.The method used to fabricate the COF@CB@MPDA/GCE sensor could be easily adapted for the selective recognition and detection of other antibacterial agents and organic pollutants in the environment.展开更多
Large-scale bismuth vanadate(BiVO_(4))photoanodes are critical to the practical application of photoelectrochemical water splitting devices.However,the lack of interface-modified coatings with simultaneous low cost,sc...Large-scale bismuth vanadate(BiVO_(4))photoanodes are critical to the practical application of photoelectrochemical water splitting devices.However,the lack of interface-modified coatings with simultaneous low cost,scalability,high hole transport efficiency,low impedance,and photocorrosion resistance is a major challenge that prevents the practical application of large-size photoanodes.Here,we present a scalable nickel-chelated polydopamine conformal coating for modifying BiVO_(4)(BiVO_(4)@PDA-Ni,BPNi),achieving over 500 h of stable water oxidation at 0.6 VRHE.The excellent stability is attributed to the chelated Ni acting as hole oxidation sites for PDA,thereby suppressing the accumulated-holes-induced PDA decomposition.Additionally,the in situ generation of Ni(IV)facilitates the structural reorganization of PDA in the photoelectrochemical system,further enhancing the stability of the PDA matrix.The findings of PDA photodegradation,its autonomous metal ion capture within photoelectrochemical systems,and the rapid deactivation of BPNi photoanodes caused by vanadium(V)ions have all provided significant guidance for the enhancement of PDA.Our study demonstrates that nickel-chelated polydopamine can be applied to large-scale BiVO_(4) photoanodes to facilitate oxygen evolution.This will promote the development of large-scale photoanodes suitable for photoelectrochemical devices.展开更多
A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL...A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL@PD-MNPs） with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significant- ly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy, A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin （DMY） in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation.展开更多
Zirconium-based metal-organic frameworks(Zr-MOFs)have attracted widespread attention due to their high specific surface area,high porosity,abundant metal active sites and excellent hydrothermal stability.However,Zr-MO...Zirconium-based metal-organic frameworks(Zr-MOFs)have attracted widespread attention due to their high specific surface area,high porosity,abundant metal active sites and excellent hydrothermal stability.However,Zr-MOFs materials are mostly powdery in nature and thus difficult to separate from aqueous media,which limits their application in wastewater treatment.In this study,PDA/Zr-MOFs/PU foam was constructed by growing Zr-MOFs nanoparticles on a dopamine-modified polyurethane foam substrate by in-situ hydrothermal synthesis as an adsorbent for removing dyes from wastewater.The results demonstrated that the polydopamine coating improves the dispersion of the Zr-MOFs nanoparticles on the substrate and enhances the interaction between the Zr-MOFs nanoparticles and the PU foam substrate.As a result,compared with Zr-MOFs/PU foam,the prepared PDA/ZrMOFs/PU foam exhibits higher adsorption capacity for crystal violet(CV)(63.38 mg/g)and rhodamine B(RB)(67.73 mg/g),with maximum adsorption efficiencies of CV and RB of 98.4%(pH=11)and 93.5%(pH=7),respectively,at a concentration of 10 mg/L.The PDA/Zr-MOFs/PU foam can simultaneously remove CV and RB from the mixed solution.Moreover,the PDA/ZrMOFs/PU foam still exhibits high stability and reusability after five cycles.展开更多
Exosomes derived from mesenchymal stem cells are of therapeutic interest because of their important role in intracellular communication and biological regulation.On the basis of previously studied nerve conduits,we de...Exosomes derived from mesenchymal stem cells are of therapeutic interest because of their important role in intracellular communication and biological regulation.On the basis of previously studied nerve conduits,we designed a polydopamine-modified chitin conduit loaded with mesenchymal stem cell-derived exosomes that release the exosomes in a sustained and stable manner.In vitro experiments revealed that rat mesenchymal stem cell-derived exosomes enhanced Schwann cell proliferation and secretion of neurotrophic and growth factors,increased the expression of Jun and Sox2 genes,decreased the expression of Mbp and Krox20 genes in Schwann cells,and reprogrammed Schwann cells to a repair phenotype.Furthermore,mesenchymal stem cell-derived exosomes promoted neurite growth of dorsal root ganglia.The polydopamine-modified chitin conduits loaded with mesenchymal stem cell-derived exosomes were used to bridge 2 mm rat sciatic nerve defects.Sustained release of exosomes greatly accelerated nerve healing and improved nerve function.These findings confirm that sustained release of mesenchymal stem cell-derived exosomes loaded into polydopamine-modified chitin conduits promotes the functional recovery of injured peripheral nerves.展开更多
Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisite...Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the nanoparticles.The structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic properties.After covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further enhanced.This was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility.Moreover,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free radicals.As a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.展开更多
Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive ...Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive application.There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys.Herein,the epoxy resin powder coating with polydopamine modified molybdenum disulfide(MoS_(2)@PDA-EP powder coating with 0,0.1,0.2,0.5,1.0 wt.%loading)was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance.The results revealed that the addition of MoS_(2)@PDA enhanced the adhesion strength between coatings and alloys,wear resistance and corrosion protection of the powder coatings.Among them,the optimum was obtained by 0.2 wt.%MoS_(2)@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix.To conclude,MoS_(2)@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.展开更多
The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration.However,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration w...The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration.However,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose,which limits their clinical benefits.Bioactive mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth fa ctors and can activate the equivalent receptors but have simplified sequences and structures.In this study,we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth fa ctor mimetic peptides(Chi/PDA-Ps).We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional peptides.In this study,we evaluated the biocompatibility of the Chi/P DA-Ps conduits.Brain-derived neurotrophic factor mimetic peptide and vascular endothelial growth fa ctor mimetic peptide synergistically promoted prolife ration of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in vitro.The Chi/P DA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve injury.We found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius atrophy.The electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and re myelination was further resto red.These findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.展开更多
An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has be...An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis.展开更多
Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical ...Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical applications. Besides, it is necessary to endow Mg alloys with bioactive property, which is crucial for temporary bone implants. Here, a self-healing, corrosion resistant and bioactive duplex coating of plasma electrolytic oxidization(PEO)/polydopamine(PDA) is applied on AZ91 substrate using PEO and subsequent electrodeposition process. Moreover, the role of different electrodeposition times(60 s, 120 s) and dopamine concentrations(1 and 1.5 mg/ml) to improve corrosion resistance, bioactivity, biocompatibility and self-healing property and its mechanism are investigated. The results indicate that the PEO coating is efficiently sealed by the PDA, depending on the electrodeposition parameters. Noticeably, electrodeposition for 120 s in dopamine concentration of 1 mg/ml(120T-1C) results in the formation of uniform and crack-free PDA coating. Duplex PEO/PDA coatings reveal high bioactivity compared to PEO coating, owing to electrostatic interaction between PDA top-layer and calcium and phosphate ions as well as high hydrophilicity of coatings. In addition, duplex PEO/PDA coatings also show improved and more stable protective performance than the PEO and bare alloy, depending on the PDA deposition parameters. Noticeably, the corrosion current density of the 120T-1C decreases one orders of magnitude compared to PEO. In addition, the presence of a broad passivation region in the anodic polarization branch shows durable self-healing property via Zipper-like mechanism, demonstrating the duplex coating could preserve promising corrosion resistance.Furthermore, the cytocompatibility of duplex coated samples is also confirmed via interaction with MG63 cells. In summary, the PEO/PDA coating with great corrosion protection, self-healing ability, bioactivity and biocompatibility could be a promising candidate for degradable magnesium-based implants.展开更多
The increasing antibiotic treatment failure is attributed to the increasing emergence of drug-resistant bacteria,and the attachment of these bacteria to the surface of implantation materials often leads to dangerous b...The increasing antibiotic treatment failure is attributed to the increasing emergence of drug-resistant bacteria,and the attachment of these bacteria to the surface of implantation materials often leads to dangerous bacterial biofilm formation on the implant surface.Thus,this creates an urgent need to develop new antibacterial material and antifouling implants.Polydopamine(PDA),as a musselinspired material,has many advantageous properties,such as a simple preparation procedure,excellent hydrophilicity and biocompatibility,strong adhesive performance,easy functionalization,outstanding photothermal conversion effect,and strong quenching effect.PDA has increasingly attracted much interest not only for its adherence to virtually all types of surfaces but also as it provides a simple and versatile approach to functionalize material surfaces to obtain a variety of multifunctional nanomaterials.In this review,we mainly focus on the preparation and polymerization mechanism of PDA systems and then provide a compilation of several reports on the PDA surface modification of various nanomaterials and material surfaces,including metals,metal oxides,carbons,and polymers.Finally,we summarize the advantages and disadvantages of polydopamine surface-modified nanomaterials.展开更多
Detailed atomistic structures are constructed for polydopamine membranes containing different amounts of catechol and quinone groups to investigate the effect of p H value in the membrane casting solution on sorption ...Detailed atomistic structures are constructed for polydopamine membranes containing different amounts of catechol and quinone groups to investigate the effect of p H value in the membrane casting solution on sorption and diffusion of small gas molecules(water and propylene) in the membranes. Interactions between dopamine oligomers are calculated, and it is found that the interactions decrease from- 2356.52 k J·mol-1in DOP-1 to-1586.69 k J·mol-1in DOP-3 when all of the catechol groups are converted to quinone groups. The mobility of polymer segments and free volume properties of polydopamine membranes are analyzed. The sorption quantities of water and propylene in the membrane are calculated using Grand Canonical Monte Carlo method. The sorption results show that water adsorbed in DOP-1, DOP-2 and DOP-3 are 17.3, 18.6 and 20.0 mg water per gram polymer, respectively, and no propylene molecule can be adsorbed. The diffusion behavior of water molecules in the membrane is investigated by molecular dynamics simulation. The diffusion coefficients of water molecules in DOP-1, DOP-2 and DOP-3 membranes are(1.80 ± 0.52) × 10-11,(3.40 ± 0.64) × 10-11and(4.50 ± 0.92) × 10-11m2·s-1, respectively. The predicted sorption quantities and diffusion coefficients of water and propylene in the membrane present the same trends as those from experimental results.展开更多
In clinical cancer research,it is quite promising to develop multimodal synergistic therapeutic strategies.Photodynamic and photothermal synergistic therapy is a very desirable multimodal therapy strategy.Herein,we re...In clinical cancer research,it is quite promising to develop multimodal synergistic therapeutic strategies.Photodynamic and photothermal synergistic therapy is a very desirable multimodal therapy strategy.Herein,we report a facile and simple method to construct a nanotherapeutic agent for photodynamic and photothermal therapy.This nanotherapeutic agent(ZnO@Ce6-PDA)is composed of a ZnO nanoparticle core,an interlayer of photosensitizer chlorin e6(Ce6)and an outer layer of polydopamine(PDA).Due to the existence of Ce6,the ZnO@Ce6-PDA can efficiently generate singlet oxygen(1O2)under 660 nm laser irradiation.Moreover,the ZnO@Ce6-PDA can serve as a photothermal agent,because of the excellent photothermal conversion efficiency of the PDA coating layer in the presence of 780 nm laser.Experiment results demonstrated that the designed nanotherapeutic agent had outstanding phototoxicity upon the combination of laser irradiation at 660 and 780 nm.Thus,our work proves that the ZnO@Ce6-PDA is a promising photodynamic/photothermal dual-modal nanotherapeutic agent for enhanced cancer therapy.展开更多
Two-dimensional materials have been proved to be effective in improving the performance of anticorrosive coatings.However,most of the reported two-dimensional materials only have the ability to passively block corrosi...Two-dimensional materials have been proved to be effective in improving the performance of anticorrosive coatings.However,most of the reported two-dimensional materials only have the ability to passively block corrosive media and cannot effectively inhibit localized corrosion reactions at the metal/coating interface.Herein,we first synthesized a novel polyaniline(PANI)nanosheet with both barrier and passivation functions for metals.In addition,polydopamine(PDA)wrapped PANI nanosheets(PANI@PDA)were obtained by in situ self-polymerization reaction of dopamine on the PANI surface,which enhance its interfacial interaction with polymeric resin.The chemical structure,morphology and corrosion inhibition properties of the nanosheets were systematically analyzed.The incorporated PANI@PDA nanosheets in composite coating provide a longer penetration path for corrosive mediums.Secondly,the uniformly dispersed two-dimensional nanosheets induce the formation of passivation film on the metal substrate.The protective effect of PANI@PDA nanosheets on coatings was verified by electrochemical impedance spectroscopy(EIS).Results indicated that the prepared composite coating exhibited excellent corrosion resistance throughout the test cycle.This simple and effective modification strategy based on conductive polymers provides a new insight into the development of environmentally adaptive composite coatings with active and passive protection.展开更多
Integration of strong upconversion emission with deep tissue penetration and stable photothermal generation is of great significance for imaging-guided photothermal therapy under infrared excitation.Herein,the NaYF_(4...Integration of strong upconversion emission with deep tissue penetration and stable photothermal generation is of great significance for imaging-guided photothermal therapy under infrared excitation.Herein,the NaYF_(4):Yb^(3+),Ho^(3+),Ce^(3+)@NaGdF_(4):Yb^(3+),Nd^(3+)@NaGdF_(4)core-shell-shell upconversion nanoparticles(UCNPs) with increasing Ce^(3+)doping concentration were firstly synthesized,in which the size manipulation,enhanced red to green emission intensity ratio(IR/IG),980 and 808 nm dual-modal excitations,as well as improved total upco nversion emission intensity can be achieved.After the coating of polydopamine(PDA) through dopamine spontaneous polymerization on the UCNPs surface under alkaline condition,the obtained UCNP@PDA nanocomposites show efficient photothermal effect under 808 nm excitation,while the thickness variation of PDA can be indicated by the upconversion spectra under 980 nm excitation.Interestingly,the photothermal effect of the UCNP@PDA nanocomposites with high IR/IGratio is mo re stable with PDA thickness variation,which bene fits from the structure design that allows PDA to simultaneously absorb the visible emission from inside UCNPs and the external 808 nm infrared light.Further in vitro cytotoxicity assay and photothermal therapy demonstrate that the UCNP@PDA nanocomposite has good biocompatibility and ability to kill tumor cells by photothermal effect under 808 nm excitation.This research may provide a nanoplatform for integrating deep bioimaging with highly stable photothermal therapy without the sacrifice of radiative transitions of rare earth ions.展开更多
Lignocellulose has the potential to become a bio-based adsorbent due to its biodegradability and renewability.In this study,a novel polydopamine functionalized-lignin(lignin@PDA),prepared via self-polymerization of do...Lignocellulose has the potential to become a bio-based adsorbent due to its biodegradability and renewability.In this study,a novel polydopamine functionalized-lignin(lignin@PDA),prepared via self-polymerization of dopamine(PDA)on lignin,was used as a bio-based adsorbent for rapid scavenging of hexavalent chromium(Cr(VI)).The morphology,functional groups,crystalline structure,and chemical composition of lignin@PDA were characterized with a scanning electron microscope-energy dispersive spectrometer,Fourier transform infrared spectroscopy,X-ray diffraction,and X-ray photoelectron spectroscopy.The Cr(VI)adsorption process of lignin@PDA was studied using batch experiments as a function of pH,ionic strength,adsorbent dose,and contact time at room temperature.The adsorption rate of lignin@PDA was five times greater than that of the unmodified lignin,with a maximum adsorption capacity of 102.6 mg/g in an acidic medium.The adsorption of Cr(VI)on lignin@PDA fit the pseudo-secondorder equation and the Freundlich model,indicating that the adsorption process was mainly dominated by chemisorption and surface complexation.The thermodynamic parameters showed that adsorption of Cr(VI)on lignin@PDA was an endothermic and spontaneous process.The X-ray absorption fine structure results showed that sorption and reduction of Cr(VI)into Cr(II)occurred simultaneously on lignin.Moreover,PDA coating not only improved the reactivity of lignin but also promoted the complete reduction of Cr(VI)by lignin.According to these results,polydopamine functionalized-lignin is a promising bio-based adsorbent for immobilization of Cr(VI)from wastewater.展开更多
Most recently,cobalt sulfide(CoS)nanospheres(NSs)have been demonstrated as an ideal high-efficient photothermal agent for tumor elimination.Howeve r,the surface of CoS NSs is lack of functio nal chemical groups or act...Most recently,cobalt sulfide(CoS)nanospheres(NSs)have been demonstrated as an ideal high-efficient photothermal agent for tumor elimination.Howeve r,the surface of CoS NSs is lack of functio nal chemical groups or active radicals to incorporate therapeutic agents,which tremendously hinders their versatile utilization in medical field.Here,surface activation of CoS NSs was realized through the growth of polydopamine(PDA)in situ via alkaline-triggered polymerization.Upon the formation of CoS@PDA NSs,thiol-polyethylene glycol(SH-PEG)and chemotherapeutic agent of doxorubicin(DOX)were loaded onto the particle surface by means ofπ-πelectrostatic interaction and Michael addition reactions.Assynthesized CoS@PDA/PEG/DOX(CoPPD)NSs exhibited an admirable photothermal property and high loading capacity of DOX(44.6%).Furthermore,drug release can be accelerated under a more acidic pH condition mimicking tumor microenvironment(TME),ascribed to the protonation of amino group in DOX molecules.Finally,a strong chemotherapeutic-enhanced photothermal therapeutic effect was demonstrated toward solid tumor under near-infrared(NIR)light irradiation without causing significant systemic toxicity.In this regard,this paradigm may offer valuable guidance for the design of multifunctional CoS-based nanoagents for medical treatment.展开更多
基金supported by the National Natural Science Foundation of China(Nos.82301156,32371377,and 52203131)Leading Talent Project of Guangzhou Development District(No.2020L013)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(No.LTGY23H140001)the Fundamental Research Funds for Wenzhou Medical University(No.KYYW202208)。
文摘Polydopamine(PD)coating,one of the simplest and most versatile surface functionalization method faces challenges in terms of stability and reactivity.In this study,we propose an in situ dynamic reassembly approach to address these challenges.By immersing a pre-deposited PD coating in a strong alkaline solution containing poly(allylamine)hydrochloride(PAH),the dissociated PD oligomers undergo covalent crosslinking in situ,leading to the formation of a reconstructed PDPA coating enriched with stable amino groups through thorough crosslinking.The PDPA coating demonstrates superior chemical and mechanical stability compared to PD,while enhancing multifunctional properties and offering improved surface functional modification potential.The PDPA coating holds promise in materials science,biomedical engineering,and nanotechnology,enabling versatile surface modification and functionalization in extreme conditions.
基金supported by Key Scientific Research Projects of Colleges and Universities in Henan Province(No.23ZX016)University Innovation Research and Training Program(No.202110467004)the Distinguished Professor Program of Institutions of Higher Learning in Henan Province,National Key R&D Program of China(No.2019YFE0101200).
文摘Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-sterilizable polypropylene-based membrane for face masks to address challenges associated with infection transmission prevention.The membrane,created using 3D printing,underwent functionalization with zinc oxide(ZnO)and polydopamine(PDA)-TEMPO to achieve broad-spectrum light absorption and facilitate self-sterilization through photocatalytic and photothermal effects upon light exposure.The hydrophobic surface(water contact angle:133±2°)minimized moisture accumulation,and the membrane exhibited robust mechanical properties,including shear strength(1.25±0.5kPa)and peel resistance strength(112.8±11.2kPa).The evaluation demonstrated stability in airflow(0-500cm^(3)/s)and excellent aerosol filtration efficiency(94.8±0.6%)for particles(PM 0.3,PM 2.5,PM 10),comparable to commercial masks.The membrane showed antibacterial efficacy over five uses in a simulated respiratory environment.Safety assessments confirmed biocompatibility through cytocompatibility and skin irritation assays.In conclusion,this membrane offers efficient filtration and photo-triggered sterilization,presenting a promising solution for next-generation face masks to address concerns related to reuse,disposal,and infection control.
基金the financial supports of Fundamental Research Funds for the Central Universities,China(Nos.YWF-23-L-1012,YWF-22-L-1017)。
文摘The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing the mussel-inspired Polydopamine(PDA)to introduce a strong chemical-physical bonding between titanium and PEEK.The enhanced Fiber-Metal Laminate(FML)exhibits a significant 48.82%enhancement in Interlaminar Shear Strength(ILSS).In addition,it alters the failure mode of the FML from single metal-resin interlaminar delamination to a multi-mechanism,including debonding,delamination of different composite layers,leading to a 28.57%improvement in maximum displacement.
基金supported by the Project of Key R&D Program of Shandong Province(2023CXGC010712).Geoffrey I.N.
文摘In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF).COF@CB@MPDA possessed good water dispersibility and was synthesized by the selfpolymerization of dopamine under alkaline conditions in the presence of the COF,CB and CF.The high surface area COF enhanced the adsorption of CF,whilst CB gave the composites high electrical conductivity to improve the sensitivity of the proposed COF@CB@MPDA/glassy carbon electrode(GCE)sensor.The specific recognition of CF by COF@CB@MPDA involved hydrogen bonding and van der Waals interactions.Under optimized conditions,the sensor showed a good linear relationship with CF concentration over the range of 5.0×10^(–7)and 1.0×10^(–4)mol/L,with a limit of detection(LOD)of 9.53×10^(–8)mol/L.Further,the developed sensor exhibited high selectivity,repeatability and stability for CF detection in milk and milk powders.The method used to fabricate the COF@CB@MPDA/GCE sensor could be easily adapted for the selective recognition and detection of other antibacterial agents and organic pollutants in the environment.
基金support by National Natural Science Foundation of China(NSFC,Grant No.22379153 and 22109128)Ningbo Science And Technology Bureau:Ningbo Key Research and Development Project(2023Z147)Ningbo 3315 Program(2018A-13-C).
文摘Large-scale bismuth vanadate(BiVO_(4))photoanodes are critical to the practical application of photoelectrochemical water splitting devices.However,the lack of interface-modified coatings with simultaneous low cost,scalability,high hole transport efficiency,low impedance,and photocorrosion resistance is a major challenge that prevents the practical application of large-size photoanodes.Here,we present a scalable nickel-chelated polydopamine conformal coating for modifying BiVO_(4)(BiVO_(4)@PDA-Ni,BPNi),achieving over 500 h of stable water oxidation at 0.6 VRHE.The excellent stability is attributed to the chelated Ni acting as hole oxidation sites for PDA,thereby suppressing the accumulated-holes-induced PDA decomposition.Additionally,the in situ generation of Ni(IV)facilitates the structural reorganization of PDA in the photoelectrochemical system,further enhancing the stability of the PDA matrix.The findings of PDA photodegradation,its autonomous metal ion capture within photoelectrochemical systems,and the rapid deactivation of BPNi photoanodes caused by vanadium(V)ions have all provided significant guidance for the enhancement of PDA.Our study demonstrates that nickel-chelated polydopamine can be applied to large-scale BiVO_(4) photoanodes to facilitate oxygen evolution.This will promote the development of large-scale photoanodes suitable for photoelectrochemical devices.
基金supported by the National Natural Science Foundation of China(21336002,21222606,21376096)the Key Program of Guangdong Natural Science Foundation(S2013020013049)+1 种基金the Fundamental Research Funds for the Chinese Universities(2015PT002,2015ZP009)the Program of State Key Laboratory of Pulp and Paper Engineering(2015C04)~~
文摘A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles （PD-MNPs） was prepared and characterized. The widely used Aspetyillus niger lipase （ANL） was immobilized on the PD-MNPs （ANL@PD-MNPs） with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significant- ly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy, A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin （DMY） in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation.
基金supported by the National Natural Science Foundation of China(No.51703234)the China Postdoctoral Science Foundation(No.2018M632438)+3 种基金the Zhejiang Provincial Natural Science Foundation of China(No.LY17E030010)the Natural Science Foundation of Ningbo City of China(Nos.2018A610036,2018A610219,2018A610029,2019A610159,and 2019A610005)the Scientific Research Fund of Zhejiang Provincial Education Department(No.Y201839180)the K.C.Wong Magna Fund in Ningbo University。
文摘Zirconium-based metal-organic frameworks(Zr-MOFs)have attracted widespread attention due to their high specific surface area,high porosity,abundant metal active sites and excellent hydrothermal stability.However,Zr-MOFs materials are mostly powdery in nature and thus difficult to separate from aqueous media,which limits their application in wastewater treatment.In this study,PDA/Zr-MOFs/PU foam was constructed by growing Zr-MOFs nanoparticles on a dopamine-modified polyurethane foam substrate by in-situ hydrothermal synthesis as an adsorbent for removing dyes from wastewater.The results demonstrated that the polydopamine coating improves the dispersion of the Zr-MOFs nanoparticles on the substrate and enhances the interaction between the Zr-MOFs nanoparticles and the PU foam substrate.As a result,compared with Zr-MOFs/PU foam,the prepared PDA/ZrMOFs/PU foam exhibits higher adsorption capacity for crystal violet(CV)(63.38 mg/g)and rhodamine B(RB)(67.73 mg/g),with maximum adsorption efficiencies of CV and RB of 98.4%(pH=11)and 93.5%(pH=7),respectively,at a concentration of 10 mg/L.The PDA/Zr-MOFs/PU foam can simultaneously remove CV and RB from the mixed solution.Moreover,the PDA/ZrMOFs/PU foam still exhibits high stability and reusability after five cycles.
基金supported by the National Natural Science Foundation of China,Nos.31771322,31571235the National Science Foundation of Beijing,No.7212121+3 种基金Beijing Science Technology New Star Cross Subject,No.2018019Science and Technology Plan Project of Shenzhen,No.JCYJ 20190806162205278the Key Laboratory of Trauma and Neural Regeneration(Peking University),Ministry of Educationa grant from National Center for Trauma Medicine,No.BMU2020XY005-01(all to PXZ).
文摘Exosomes derived from mesenchymal stem cells are of therapeutic interest because of their important role in intracellular communication and biological regulation.On the basis of previously studied nerve conduits,we designed a polydopamine-modified chitin conduit loaded with mesenchymal stem cell-derived exosomes that release the exosomes in a sustained and stable manner.In vitro experiments revealed that rat mesenchymal stem cell-derived exosomes enhanced Schwann cell proliferation and secretion of neurotrophic and growth factors,increased the expression of Jun and Sox2 genes,decreased the expression of Mbp and Krox20 genes in Schwann cells,and reprogrammed Schwann cells to a repair phenotype.Furthermore,mesenchymal stem cell-derived exosomes promoted neurite growth of dorsal root ganglia.The polydopamine-modified chitin conduits loaded with mesenchymal stem cell-derived exosomes were used to bridge 2 mm rat sciatic nerve defects.Sustained release of exosomes greatly accelerated nerve healing and improved nerve function.These findings confirm that sustained release of mesenchymal stem cell-derived exosomes loaded into polydopamine-modified chitin conduits promotes the functional recovery of injured peripheral nerves.
基金This work was financially supported by Jilin Provincial Science and Technology Project(No.YDZJ202101-ZYTS054)the National Science Fund for Distinguished Young Scholars(No.51925104)the National Natural Science Foundation of China(No.51871162).
文摘Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the nanoparticles.The structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic properties.After covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further enhanced.This was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility.Moreover,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free radicals.As a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.
基金financial support provided by the National Natural Science Foundation of China(Grant No.U1806225)the National Natural Science Foundation of China(Grant No.51908092)the Joint Funds of the National Natural Science Foundation of China-Guangdong(Grant No.U1801254)。
文摘Epoxy resin powder coating has been successfully applied on the corrosion protection of magnesium lithium alloys.However,poor wear resistance and microcracks formed during the solidification have limited it extensive application.There are limited approaches to exploit such anti-corrosion and mechanical properties of magnesium lithium alloys.Herein,the epoxy resin powder coating with polydopamine modified molybdenum disulfide(MoS_(2)@PDA-EP powder coating with 0,0.1,0.2,0.5,1.0 wt.%loading)was well prepared by melt extrusion to investigate its anticorrosion performance and wear resistance.The results revealed that the addition of MoS_(2)@PDA enhanced the adhesion strength between coatings and alloys,wear resistance and corrosion protection of the powder coatings.Among them,the optimum was obtained by 0.2 wt.%MoS_(2)@PDA-EP powder coating which could be attributed to well dispersion and efficient adhesion with coating matrix.To conclude,MoS_(2)@PDA-EP powder coating is meaningfully beneficial for the anticorrosive and wear performance improvement of magnesium lithium alloys.
基金the National Natural Science Foundation of China,Nos.31771322,31571235the Natural Science Foundation of Beijing,No.7212121+3 种基金Beijing Science Technology New Star Cross Subject of China,No.2018019Shenzhen Science and Technology Plan Project of China,No.JCYJ 20190806162205278the Key Laboratory of Trauma and Neural Regeneration(Peking University),Ministry of Educationa grant from National Center for Trauma Medicine,No.BMU2020XY005-01(all to PXZ)。
文摘The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration.However,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose,which limits their clinical benefits.Bioactive mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth fa ctors and can activate the equivalent receptors but have simplified sequences and structures.In this study,we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth fa ctor mimetic peptides(Chi/PDA-Ps).We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional peptides.In this study,we evaluated the biocompatibility of the Chi/P DA-Ps conduits.Brain-derived neurotrophic factor mimetic peptide and vascular endothelial growth fa ctor mimetic peptide synergistically promoted prolife ration of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in vitro.The Chi/P DA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve injury.We found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius atrophy.The electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and re myelination was further resto red.These findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.21475046,21427809)
文摘An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis.
文摘Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical applications. Besides, it is necessary to endow Mg alloys with bioactive property, which is crucial for temporary bone implants. Here, a self-healing, corrosion resistant and bioactive duplex coating of plasma electrolytic oxidization(PEO)/polydopamine(PDA) is applied on AZ91 substrate using PEO and subsequent electrodeposition process. Moreover, the role of different electrodeposition times(60 s, 120 s) and dopamine concentrations(1 and 1.5 mg/ml) to improve corrosion resistance, bioactivity, biocompatibility and self-healing property and its mechanism are investigated. The results indicate that the PEO coating is efficiently sealed by the PDA, depending on the electrodeposition parameters. Noticeably, electrodeposition for 120 s in dopamine concentration of 1 mg/ml(120T-1C) results in the formation of uniform and crack-free PDA coating. Duplex PEO/PDA coatings reveal high bioactivity compared to PEO coating, owing to electrostatic interaction between PDA top-layer and calcium and phosphate ions as well as high hydrophilicity of coatings. In addition, duplex PEO/PDA coatings also show improved and more stable protective performance than the PEO and bare alloy, depending on the PDA deposition parameters. Noticeably, the corrosion current density of the 120T-1C decreases one orders of magnitude compared to PEO. In addition, the presence of a broad passivation region in the anodic polarization branch shows durable self-healing property via Zipper-like mechanism, demonstrating the duplex coating could preserve promising corrosion resistance.Furthermore, the cytocompatibility of duplex coated samples is also confirmed via interaction with MG63 cells. In summary, the PEO/PDA coating with great corrosion protection, self-healing ability, bioactivity and biocompatibility could be a promising candidate for degradable magnesium-based implants.
基金This study was financially supported by the National Natural Science Foundation of China(Nos.21875014 and 52073013).
文摘The increasing antibiotic treatment failure is attributed to the increasing emergence of drug-resistant bacteria,and the attachment of these bacteria to the surface of implantation materials often leads to dangerous bacterial biofilm formation on the implant surface.Thus,this creates an urgent need to develop new antibacterial material and antifouling implants.Polydopamine(PDA),as a musselinspired material,has many advantageous properties,such as a simple preparation procedure,excellent hydrophilicity and biocompatibility,strong adhesive performance,easy functionalization,outstanding photothermal conversion effect,and strong quenching effect.PDA has increasingly attracted much interest not only for its adherence to virtually all types of surfaces but also as it provides a simple and versatile approach to functionalize material surfaces to obtain a variety of multifunctional nanomaterials.In this review,we mainly focus on the preparation and polymerization mechanism of PDA systems and then provide a compilation of several reports on the PDA surface modification of various nanomaterials and material surfaces,including metals,metal oxides,carbons,and polymers.Finally,we summarize the advantages and disadvantages of polydopamine surface-modified nanomaterials.
基金Supported by the National Science Fund for Distinguished Young Scholars(21125627)the National Natural Science Foundation of China(21306131)+2 种基金Specialized Research Fund for the Doctoral Program of Higher Education(20120032120009)Seed Foundation of Tianjin Universitythe Programme of Introducing Talents of Disciplineto Universities(B06006)
文摘Detailed atomistic structures are constructed for polydopamine membranes containing different amounts of catechol and quinone groups to investigate the effect of p H value in the membrane casting solution on sorption and diffusion of small gas molecules(water and propylene) in the membranes. Interactions between dopamine oligomers are calculated, and it is found that the interactions decrease from- 2356.52 k J·mol-1in DOP-1 to-1586.69 k J·mol-1in DOP-3 when all of the catechol groups are converted to quinone groups. The mobility of polymer segments and free volume properties of polydopamine membranes are analyzed. The sorption quantities of water and propylene in the membrane are calculated using Grand Canonical Monte Carlo method. The sorption results show that water adsorbed in DOP-1, DOP-2 and DOP-3 are 17.3, 18.6 and 20.0 mg water per gram polymer, respectively, and no propylene molecule can be adsorbed. The diffusion behavior of water molecules in the membrane is investigated by molecular dynamics simulation. The diffusion coefficients of water molecules in DOP-1, DOP-2 and DOP-3 membranes are(1.80 ± 0.52) × 10-11,(3.40 ± 0.64) × 10-11and(4.50 ± 0.92) × 10-11m2·s-1, respectively. The predicted sorption quantities and diffusion coefficients of water and propylene in the membrane present the same trends as those from experimental results.
基金supported in part by the Key Project of Natural Science Foundation of China (Nos.21775036,21675046,21735002, 21521063 and 21874035)the Key Point Research and Invention Program of Hunan Province (No.2017DK2011)+1 种基金the Research Foundation of Education Bureau of Hunan Province (No.18B027)the Hunan Provincial Natural Science Foundation (No.2018JJ2033)
文摘In clinical cancer research,it is quite promising to develop multimodal synergistic therapeutic strategies.Photodynamic and photothermal synergistic therapy is a very desirable multimodal therapy strategy.Herein,we report a facile and simple method to construct a nanotherapeutic agent for photodynamic and photothermal therapy.This nanotherapeutic agent(ZnO@Ce6-PDA)is composed of a ZnO nanoparticle core,an interlayer of photosensitizer chlorin e6(Ce6)and an outer layer of polydopamine(PDA).Due to the existence of Ce6,the ZnO@Ce6-PDA can efficiently generate singlet oxygen(1O2)under 660 nm laser irradiation.Moreover,the ZnO@Ce6-PDA can serve as a photothermal agent,because of the excellent photothermal conversion efficiency of the PDA coating layer in the presence of 780 nm laser.Experiment results demonstrated that the designed nanotherapeutic agent had outstanding phototoxicity upon the combination of laser irradiation at 660 and 780 nm.Thus,our work proves that the ZnO@Ce6-PDA is a promising photodynamic/photothermal dual-modal nanotherapeutic agent for enhanced cancer therapy.
基金fundings from the National Natural Science Foundation of China(nos.51971121 and 52002228)the National Natural Science Foundation of China-Shandong Joint Fund for Marine Science Research Centers(CN)(No.U2106216)the Qingdao Marine Science and Technology Innovation Project(No.22-3-3-hygg-27-hy).
文摘Two-dimensional materials have been proved to be effective in improving the performance of anticorrosive coatings.However,most of the reported two-dimensional materials only have the ability to passively block corrosive media and cannot effectively inhibit localized corrosion reactions at the metal/coating interface.Herein,we first synthesized a novel polyaniline(PANI)nanosheet with both barrier and passivation functions for metals.In addition,polydopamine(PDA)wrapped PANI nanosheets(PANI@PDA)were obtained by in situ self-polymerization reaction of dopamine on the PANI surface,which enhance its interfacial interaction with polymeric resin.The chemical structure,morphology and corrosion inhibition properties of the nanosheets were systematically analyzed.The incorporated PANI@PDA nanosheets in composite coating provide a longer penetration path for corrosive mediums.Secondly,the uniformly dispersed two-dimensional nanosheets induce the formation of passivation film on the metal substrate.The protective effect of PANI@PDA nanosheets on coatings was verified by electrochemical impedance spectroscopy(EIS).Results indicated that the prepared composite coating exhibited excellent corrosion resistance throughout the test cycle.This simple and effective modification strategy based on conductive polymers provides a new insight into the development of environmentally adaptive composite coatings with active and passive protection.
基金Project supported by the National Natural Science Foundation of China (51872200,51772210)the Natural Science Foundation of Shanghai(18ZR1441900)the National Key Research and Development Projects(2018YFC1106302)。
文摘Integration of strong upconversion emission with deep tissue penetration and stable photothermal generation is of great significance for imaging-guided photothermal therapy under infrared excitation.Herein,the NaYF_(4):Yb^(3+),Ho^(3+),Ce^(3+)@NaGdF_(4):Yb^(3+),Nd^(3+)@NaGdF_(4)core-shell-shell upconversion nanoparticles(UCNPs) with increasing Ce^(3+)doping concentration were firstly synthesized,in which the size manipulation,enhanced red to green emission intensity ratio(IR/IG),980 and 808 nm dual-modal excitations,as well as improved total upco nversion emission intensity can be achieved.After the coating of polydopamine(PDA) through dopamine spontaneous polymerization on the UCNPs surface under alkaline condition,the obtained UCNP@PDA nanocomposites show efficient photothermal effect under 808 nm excitation,while the thickness variation of PDA can be indicated by the upconversion spectra under 980 nm excitation.Interestingly,the photothermal effect of the UCNP@PDA nanocomposites with high IR/IGratio is mo re stable with PDA thickness variation,which bene fits from the structure design that allows PDA to simultaneously absorb the visible emission from inside UCNPs and the external 808 nm infrared light.Further in vitro cytotoxicity assay and photothermal therapy demonstrate that the UCNP@PDA nanocomposite has good biocompatibility and ability to kill tumor cells by photothermal effect under 808 nm excitation.This research may provide a nanoplatform for integrating deep bioimaging with highly stable photothermal therapy without the sacrifice of radiative transitions of rare earth ions.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ19E030017)the Research Start-up Fund(Grant No.KYS205619042)the Technological Research Project for Public Welfare of Zhejiang Province(Grant No.LGG19E030005).
文摘Lignocellulose has the potential to become a bio-based adsorbent due to its biodegradability and renewability.In this study,a novel polydopamine functionalized-lignin(lignin@PDA),prepared via self-polymerization of dopamine(PDA)on lignin,was used as a bio-based adsorbent for rapid scavenging of hexavalent chromium(Cr(VI)).The morphology,functional groups,crystalline structure,and chemical composition of lignin@PDA were characterized with a scanning electron microscope-energy dispersive spectrometer,Fourier transform infrared spectroscopy,X-ray diffraction,and X-ray photoelectron spectroscopy.The Cr(VI)adsorption process of lignin@PDA was studied using batch experiments as a function of pH,ionic strength,adsorbent dose,and contact time at room temperature.The adsorption rate of lignin@PDA was five times greater than that of the unmodified lignin,with a maximum adsorption capacity of 102.6 mg/g in an acidic medium.The adsorption of Cr(VI)on lignin@PDA fit the pseudo-secondorder equation and the Freundlich model,indicating that the adsorption process was mainly dominated by chemisorption and surface complexation.The thermodynamic parameters showed that adsorption of Cr(VI)on lignin@PDA was an endothermic and spontaneous process.The X-ray absorption fine structure results showed that sorption and reduction of Cr(VI)into Cr(II)occurred simultaneously on lignin.Moreover,PDA coating not only improved the reactivity of lignin but also promoted the complete reduction of Cr(VI)by lignin.According to these results,polydopamine functionalized-lignin is a promising bio-based adsorbent for immobilization of Cr(VI)from wastewater.
基金supported by National Natural Science Foundation of China(Nos.51703186,31671037)。
文摘Most recently,cobalt sulfide(CoS)nanospheres(NSs)have been demonstrated as an ideal high-efficient photothermal agent for tumor elimination.Howeve r,the surface of CoS NSs is lack of functio nal chemical groups or active radicals to incorporate therapeutic agents,which tremendously hinders their versatile utilization in medical field.Here,surface activation of CoS NSs was realized through the growth of polydopamine(PDA)in situ via alkaline-triggered polymerization.Upon the formation of CoS@PDA NSs,thiol-polyethylene glycol(SH-PEG)and chemotherapeutic agent of doxorubicin(DOX)were loaded onto the particle surface by means ofπ-πelectrostatic interaction and Michael addition reactions.Assynthesized CoS@PDA/PEG/DOX(CoPPD)NSs exhibited an admirable photothermal property and high loading capacity of DOX(44.6%).Furthermore,drug release can be accelerated under a more acidic pH condition mimicking tumor microenvironment(TME),ascribed to the protonation of amino group in DOX molecules.Finally,a strong chemotherapeutic-enhanced photothermal therapeutic effect was demonstrated toward solid tumor under near-infrared(NIR)light irradiation without causing significant systemic toxicity.In this regard,this paradigm may offer valuable guidance for the design of multifunctional CoS-based nanoagents for medical treatment.
