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1.
Eur J Dent Educ ; 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38148502

RESUMO

INTRODUCTION: Virtual reality (VR) and haptic simulation technology have been increasingly implemented in dental training. Since the first haptic VR dental simulator (Simodont) was introduced 10 years ago, it has been applied in more than 40 universities in mainland China. This scoping review aimed to review literature, showcasing the teaching reform of dental virtual simulation in mainland China to global dental education peers. METHODS: This scoping review was conducted using the PRISMA extension for scoping review guidelines. Seven electronic databases were searched, and two reviewers independently performed the selection and characterization of the studies. RESULTS: The final scoping review included 12 studies. Four studies focused on the G. V. Black class II cavity, three on manual dexterity skills training, two on full metal crown preparation, one on pulpal access and coronal cavity preparation, one on flipped classroom teaching, and one on 'doctor-patient communication' skills. DISCUSSION: The most critical scenarios, self-assessment, working posture, curriculum setting, training and cost are analysed and discussed. CONCLUSION: Haptic simulation technology is a valuable complementary tool to the phantom head in dental education. The combined utilization of these two training devices has been superior to either in isolation. However, there is a lack of research on the sequencing of the two systems, as well as the appropriate distribution of curriculum between them. It is necessary for educators to organize or engage in experience sharing, collaboration and knowledge dissemination. These actions are essential for promoting effective teaching within dental educational institutions.

2.
Molecules ; 26(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530499

RESUMO

"Smart" polymeric microcapsules with excellent permeability of membranes have drawn considerable attention in scientific and industrial research such as drug delivery carriers, microreactors, and artificial organelles. In this work, hybrid hollow polymeric microcapsules (HPs) containing redox-active gold-sulfide bond were prepared with bovine serum albumin, inorganic metal cluster (AuNCs), and poly(N-isopropylacrylamide) conjugates by using Pickering emulsion method. HPs were transferred from water-in-oil to water-in-water by adding PEGbis(N-succinimidylsuccinate). To achieve redox-responsive membrane, the Au-S bond units incorporated into the microcapsules' membranes, allowed us to explore the effects of a new stimuli, that is, the redox Au-S bond breaking on the microcapsules' membranes. The permeability of these hybrid hollow polymeric microcapsules could be sensitively tuned via adding environment-friendly hydrogen peroxide (H2O2), resulting from a fast fracture of Au-S bond. Meanwhile, AuNCs and conjugates could depart from the microcapsules, and enhance the permeability of the membrane. Based on the excellent permeability of the membrane, phosphatase was encapsuled into HPs and p-nitrophenyl phosphate as a substrate. After adding 1 × 10-2 and 1 × 10-4 M H2O2, the catalytic efficiency was nearly 4.06 and 2.22 times higher than that of HPs in the absence of H2O2, respectively. Hence, the unique redox-responsive HPs have potential applications in biocatalytic reaction, drug delivery, and materials as well as in bioscience.


Assuntos
Nitrofenóis/química , Compostos Organofosforados/química , Monoéster Fosfórico Hidrolases/metabolismo , Polímeros/síntese química , Resinas Acrílicas/química , Cápsulas , Catálise , Ouro/química , Peróxido de Hidrogênio/química , Oxirredução , Monoéster Fosfórico Hidrolases/química , Polímeros/química , Soroalbumina Bovina/química , Sulfetos/química , Propriedades de Superfície
3.
Angew Chem Int Ed Engl ; 55(25): 7095-100, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27144816

RESUMO

A facile route to hierarchically organized multicompartmentalized proteinosomes based on a recursive Pickering emulsion procedure using amphiphilic protein-polymer nanoconjugate building blocks is described. The number of incarcerated guest proteinosomes within a single host proteinosome is controlled, and enzymes and genetic polymers encapsulated within targeted subcompartments to produce chemically organized multi-tiered structures. Three types of spatiotemporal response-retarded concomitant release, synchronous release or hierarchical release of dextran and DNA-are demonstrated based on the sequential response of the host and guest membranes to attack by protease, or through variations in the positioning of disulfide-containing cross-links in either the host or guest proteinosomes integrated into the nested architectures. Overall, our studies provide a step towards the construction of hierarchically structured synthetic protocells with chemically and spatially integrated proto-organelles.


Assuntos
Preparações de Ação Retardada/química , Emulsões/química , Nanoconjugados/química , Polímeros/química , Proteínas/química , Tensoativos/química , Células Artificiais/química , DNA/administração & dosagem , Dextranos/administração & dosagem
4.
Chemosphere ; 307(Pt 1): 135780, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35870608

RESUMO

Thermosetting unsaturated polyester resin (UPR) composites were found widespread industrial applications. However, the numerous stable carbon-carbon bonds in cross-linked networks made them intractable for degradation, causing the large-scale composite wastes. Here a nanoscale Fe0 catalyst in-situ forming strategy was exploited to nondestructively recycle carbon fiber (CF) from UPR composites via Fenton-like reaction. The nano-Fe0 catalyst employed in this strategy activated H2O2 for removing UPR, featuring mild conditions and efficient degradation ability. Aiming at facile growth of the catalyst, a porous UPR was achieved by the hydrolysis of alkalic system. The nanoscale Fe0 catalyst was subsequently formed in-situ on the surface of hydrolyzed resin by borohydride reduction. Benefiting from fast mass transfer, the in-situ grown nano-Fe0 showed more efficient degradation ability than added nano-Fe0 or Fe2+ catalyst during Fenton-like reaction. The experiments indicated that hydrolyzed resin could be degraded more than 90% within 80 min, 80 °C. GC-MS, FT-IR analysis and Density functional theory (DFT) calculation were conducted to explained the fracture processes of carbon skeleton in hydrolyzed resin. Especially, a remarkable recovery process of CF from composites was observed, with a 100 percent elimination of resin. The recycled CF cloth exhibited a 99% strength retention and maintained the textile structure, microtopography, chemical structure, resulting in the nondestructive reclaim of CF. This in-situ formed nanoscale Fe0 catalytic degradation strategy may provide a promising practical application for nondestructively recycle CF from UPR composites.


Assuntos
Peróxido de Hidrogênio , Ferro , Boroidretos , Carbono , Fibra de Carbono , Catálise , Peróxido de Hidrogênio/química , Ferro/química , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier
5.
ACS Sens ; 6(8): 2938-2951, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34328311

RESUMO

A biocompatible, flexible, yet robust conductive composite hydrogel (CCH) for wearable pressure/strain sensors has been achieved by an all-solution-based approach. The CCH is rationally constructed by in situ polymerization of aniline (An) monomers in the polyvinyl alcohol (PVA) matrix, followed by the cross-linking of PVA with glutaraldehyde (GA) as the cross-linker. The unique multiple synergetic networks in the CCH including strong chemical covalent bonds and abundance of weak physical cross-links, i.e., hydrogen bondings and electrostatic interactions, impart excellent mechanical strength (a fracture tensile strength of 1200 kPa), superior compressibility (ε = 80%@400 kPa), outstanding stretchability (a fracture strain of 670%), high sensitivity (0.62 kPa-1 at a pressure range of 0-1.0 kPa for pressure sensing and a gauge factor of 3.4 at a strain range of 0-300% for strain sensing, respectively), and prominent fatigue resistance (1500 cycling). As the flexible wearable sensor, the CCH is able to monitor different types of human motion and diagnostically distinguish speaking. As a proof of concept, a sensing device has been designed for the real-time detection of 2D distribution of weight or pressure, suggesting its promising potentials for electronic skin, human-machine interaction, and soft robot applications.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Humanos , Monitorização Fisiológica , Álcool de Polivinil
6.
ACS Appl Mater Interfaces ; 12(1): 1427-1435, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31847519

RESUMO

Highly stretchable fiber-based strain sensor is essential to develop various applications in intelligent textiles, biomedical electronics, and integrated circuits. Although several fiber-based strain sensors have been reported, attaining the balance between excellent stretchability, high conductivity, and controllable sensitivity remains challenging. Herein, we present a facile approach for fabricating highly conductive, stretchable, and sensitive fiber strain sensors by synthesizing poly(vinyl alcohol)/Ag nanoparticle composite coating through aqueous in situ reduction on a stretchable fiber with a braided structure. The conductive coating with a flexible structure shows an ultrahigh conductivity of 120 903 S/cm. The unique braided structure and dense conductive Ag network enable the strain sensor to simultaneously exhibit 150% of strain sensing, controllable gauge factor from 1.85 to 8.14 within 65% strain, and a rapid response time of 75 ms. Meanwhile, long-term durability and low hysteresis are other initial features of the fiber-based strain sensor. Most importantly, the fiber-based strain sensor is capable of detecting human motions, including vocal cord vibration, finger movements, walking, and running, exhibiting significant potential in real-time monitoring and intelligent textiles.


Assuntos
Técnicas Biossensoriais , Monitorização Fisiológica , Entorses e Distensões/diagnóstico , Têxteis , Elastômeros/química , Condutividade Elétrica , Humanos , Nanopartículas Metálicas/química , Movimento/fisiologia , Prata/química , Entorses e Distensões/fisiopatologia , Água/química , Dispositivos Eletrônicos Vestíveis
7.
Acta Chim Slov ; 67(2): 462-468, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33855553

RESUMO

Inorganic structures with functionalized polymers play essential roles in diverse biological trends. Herein, thermal and CO2 dual-stimuli nanomaterials composed of mesoporous silica nanoparticles (MSN) anchored with two grafted copolymers: poly(3-methacryloxypropyltrimethoxysilane) "PMPS" & poly(N,N-dimethylaminoethyl methacrylate) "PDMAEMA" were synthesized via one-step reaction and characterized by BET as well as BJH methods to estimate pore sizes, pore volumes, and surface areas. The smart PDMAEMA acted as an active gatekeeper to adjust the loading or in vitro release processes of a fungicidal drug-loaded inside the mesopores by altering temperature or CO2 of the tested environment. Furthermore, treating the nanomaterials by CO2 for a few minutes was found to have a bactericidal effect with promising results as indicated by the disk diffusion technique. In general, the positive biological activity against selected strains of bacteria and fungi indicates that these particles may be helpful for engineering more efficient antifungal or antibacterial agents for pharmaceutical applications.


Assuntos
Portadores de Fármacos/química , Metacrilatos/química , Nanopartículas/química , Nylons/química , Silanos/química , Dióxido de Silício/química , Anidulafungina/química , Anidulafungina/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Dióxido de Carbono/química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Metacrilatos/síntese química , Testes de Sensibilidade Microbiana , Nylons/síntese química , Porosidade , Silanos/síntese química , Tetraciclina/química , Tetraciclina/farmacologia
8.
Sci Robot ; 5(45)2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-33022630

RESUMO

Batteries with conformal shape and multiple functionalities could provide new degrees of freedom in the design of robotic devices. For example, the ability to provide both load bearing and energy storage can increase the payload and extend the operational range for robots. However, realizing these kinds of structural power devices requires the development of materials with suitable mechanical and ion transport properties. Here, we report biomimetic aramid nanofibers-based composites with cartilage-like nanoscale morphology that display an unusual combination of mechanical and ion transport properties. Ion-conducting membranes from these aramid nanofiber composites enable pliable zinc-air batteries with cyclic performance exceeding 100 hours that can also serve as protective covers in various robots including soft and flexible miniaturized robots. The unique properties of the aramid ion conductors are attributed to the percolating network architecture of nanofibers with high connectivity and strong nanoscale filaments designed using a graph theory of composite architecture when the continuous aramid filaments are denoted as edges and intersections are denoted as nodes. The total capacity of these body-integrated structural batteries is 72 times greater compared with a stand-alone Li-ion battery with the same volume. These materials and their graph theory description enable a new generation of robotic devices, body prosthetics, and flexible and soft robotics with nature-inspired distributed energy storage.


Assuntos
Materiais Biomiméticos , Fontes de Energia Elétrica , Robótica/instrumentação , Biomimética/instrumentação , Biomimética/estatística & dados numéricos , Condutividade Elétrica , Técnicas Eletroquímicas , Desenho de Equipamento , Fractais , Humanos , Lítio , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanofibras/ultraestrutura , Polímeros/química , Robótica/estatística & dados numéricos , Zinco
9.
Mater Sci Eng C Mater Biol Appl ; 99: 1153-1163, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889649

RESUMO

In this work, a poly(N-isopropylacrylamide) polymer (PNIPAAm) was prepared via the photoinduced reversible addition-fragmentation chain transfer (RAFT) polymerization using Ru(bpy)3Cl2·6H2O as photoinitiator. The design and spontaneous assembly of thiol-functionalized DNA-Thiol/PNIPAAm polymeric capsule (DNAsomes) by water-in-oil Pickering emulsion method and effective response with small molecules (Sybr green and phenanthrene) were described. The intermediate product, DNA-Thiol/PNIPAAm conjugates and DNAsomes were characterized by using 1H NMR, dynamic light scattering (DLS), SEM, TEM and UV-vis methods. The obtained results indicated that DNA-Thiol/PNIPAAm constructs assembled in a Pickering emulsion could produce DNA-based spherical DNAsomes with typically 3.3-267.7 µm in diameter. The DNAsomes showed a vesicle formation approximately 2 µm in diameter, resulting in phenanthrene molecule intercalating with DNAsomes. The phenomenon indicated that the DNA-Thiol/PNIPAAm conjugates may have potential applications in recognition polycyclic aromatic hydrocarbon molecules. The membrane of the DNAsomes could effective response toward small molecules such as Sybr green or phenanthrene, and DNAsomes has release capability of protein (BSA) under reductive agent glutathione (GSH). Our results highlight the potential of integrating aspects of supramolecular and polymer chemistry into the design and construction of DNA-polymeric capsule, guest molecule encapsulation, control delivery of drugs, recognition organic polycyclic aromatic hydrocarbon molecules and gene-directed capsule synthesis.


Assuntos
DNA/química , Soroalbumina Bovina/metabolismo , Compostos de Sulfidrila/química , Resinas Acrílicas/química , Animais , Bovinos , Cisteína/química , Ácido Ditionitrobenzoico/química , Difusão Dinâmica da Luz , Fluorescência , Íons , Metais/química , Tamanho da Partícula , Fenantrenos/química , Ácido Trinitrobenzenossulfônico/química
10.
Mater Sci Eng C Mater Biol Appl ; 94: 524-533, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423737

RESUMO

Catalytic reduction of toxic 4­nitrophenol to 4­aminophenol and dye wastewater treatment over rapid, convenient gold nanoparticles or laccase decorated hybrid vesicles catalysts has attracted much attention. In current work, a stable building block was designed with inorganic gold nanoparticles and nano-conjugates; and a hybrid giant vesicles (AuNPs@vesicles) was self-assembled by using Pickering emulsion method. The vesicles were characterized by SEM, TEM, UV-vis and DLS measurements. The results showed that a temperature-responsive multifunctional building block based on BSA-PNIPAAm and gold nanoparticles was obtained. DLS results also indicated that the length of chains on the surface of AuNPs could change shorter with increasing of temperature (>32 °C) and also obtain an average diameter to ~190 nm. A substrate-rich (high concentration of 4­nitrophenol) microenvironment can be created around AuNPs, which can dramatically accelerate the interfacial AuNPs-catalyzed reactions. The AuNPs@vesicles as catalyst in the presence of freshly prepared NaBH4 has excellent catalytic performance for reduction of 4­nitrophenol (almost 100%). After laccase was capsulated into AuNPs@vesicles, the obtained active hybrid laccase⊂AuNPs@vesicles demonstrated high catalytic decolouration efficiency (>98.5%, nearly 2.3 times higher than that of free laccase) and excellent reusability. The possible mechanisms of reduction of 4­nitrophenol and dye decolouration was proposed. These novel giant vesicles could provide some new opportunities in wastewater treatment, bottom-up synthetic biology, bioinspired microstorage/microreactor and drug/gene delivery.


Assuntos
Vermelho Congo/química , Ouro/química , Lacase/metabolismo , Substâncias Macromoleculares/química , Nanopartículas Metálicas/química , Nitrofenóis/química , Polímeros/química , Catálise , Vermelho Congo/isolamento & purificação , Difusão Dinâmica da Luz , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Espectrofotometria Ultravioleta , Fatores de Tempo
11.
Carbohydr Polym ; 207: 180-190, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599998

RESUMO

Tissue adhesion is one of the most common complications after surgery (especially after abdominal surgery), causing notable influences after the damaged tissue has healed. A physical barrier placed between the wound site and the adjacent tissues is a convenient and highly effective technique to minimize or prevent abdominal adhesions. In this work, the N, O-carboxymethyl chitosan/oxidized regenerated cellulose (N, O-CS/ORC) composite gauze was prepared. The N, O-CS/ORC composite gauze is degradable; in addition, the gauze exhibits excellent antimicrobial functionality against S. aureus and E. coli bacteria. Moreover, the notable hemostatic efficacy of the N, O-CS/ORC composite gauze was confirmed in rabbit livers/ears as models. The results showed that the N, O-CS/ORC composite gauze is nontoxic toward normal cells and can restrain the adhesion of fibroblast cells, thereby indicating its potential use in preventing tissue adhesion. In addition, the rat models for abdominal defect-cecum abrasion were used to evaluate the efficacy of N, O-CS/ORC composite gauze in preventing tissue adhesions after surgery. The results indicated that the N, O-CS/ORC composite gauze can significantly prevent postsurgical peritoneal adhesions. Finally, the potential anti-adhesion mechanism of the N, O-CS/ORC composite gauze, which may attribute to the combination of barrier function and instinct activity of N, O-CS and ORC, was investigated.


Assuntos
Antibacterianos/farmacologia , Plásticos Biodegradáveis/farmacologia , Celulose/farmacologia , Quitosana/farmacologia , Hemostáticos/farmacologia , Implantes Absorvíveis , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Bandagens , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/toxicidade , Celulose/síntese química , Celulose/química , Celulose/toxicidade , Quitosana/síntese química , Quitosana/química , Quitosana/toxicidade , Escherichia coli/efeitos dos fármacos , Feminino , Hemostáticos/síntese química , Hemostáticos/química , Hemostáticos/toxicidade , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Células NIH 3T3 , Coelhos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Aderências Teciduais/prevenção & controle
12.
J Biomed Mater Res B Appl Biomater ; 106(7): 2588-2595, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29356329

RESUMO

Effective and affordable, antibacterial and hemostatic materials are of great interests in clinical wound care practices. Herein, Enterobacteria phage T4 were incorporated in polycaprolactone/collagen I (PCL-ColI) nanofibers via electrospinning in order to eradicate Escherichia coli infection and meanwhile establish hemostasis. Tensile strength of the membrane was significantly enhanced with increased PCL ratio. Those with a collagen component above 70% were demonstrated to be more hemostatic with shorter hemostatic time and smaller amount of bleeding. On the other hand, the T4 phage incorporated PCL-ColI membrane (PCL:ColI = 30%/70%, w/w) exhibited the optimal antibacterial efficiency (above 90%). The in vivo evaluation indicated that the PCL-ColI B (30%:70%, w/w) membrane fully degraded in 8 weeks and no obvious pathological reaction to muscle and subcutaneous layer tissues in the back of rabbit was found. The novel fibrous hemostatic materials coupled with phage therapy hold great promise in designing novel antibacterial, hemostatic wound dressings that addresses concerns of antibiotic resistance. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2588-2595, 2018.


Assuntos
Antibacterianos , Bacteriófago T4/química , Colágeno , Infecções por Escherichia coli/prevenção & controle , Hemostáticos , Membranas Artificiais , Poliésteres , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Colágeno/química , Colágeno/farmacologia , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/metabolismo , Hemostáticos/química , Hemostáticos/farmacologia , Camundongos , Poliésteres/química , Poliésteres/farmacologia , Coelhos
13.
Int J Biol Macromol ; 119: 1195-1203, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30110602

RESUMO

Schwann cell (SC) is the primary structural and functional part of the peripheral nervous system, and it plays a key role in the repair and regeneration of peripheral nerve. In order to develop a suitable scaffold for SC nerve tissue engineering, three kinds of scaffolds, including pristine collagen, pure oxidized regenerated cellulose-Ca (ORCCa) and collagen/ORC-Ca composite scaffolds, have been fabricated for carrying SC in this study. SC is then seeded on the scaffolds to form SC-scaffold nerve tissue engineering composites and evaluate their biocompatibility. The chemical and physical structure of the scaffolds are investigated by FTIR, NMR and SEM. The wettability of the collagen/ORC-Ca composite scaffold is close to that of pristine collagen, and the tensile strength of the composite scaffold (0.58 MPa) is better than that of pristine collagen (0.36 MPa). Cytotoxicity, cell proliferation, cell adhesion and western blotting assays are conducted to evaluate the biocompatibility and properties of different scaffolds. The results show that the three scaffolds exhibit no toxicity, and the proliferation rate of SC on the collagen/ORC-Ca composite scaffold is significantly higher than that of the other scaffolds (p < 0.05). The number of the adhesion cells on the composite scaffold (244.67 ±â€¯13.02) is much more than that in the pure ORC-Ca group (p < 0.01). Furthermore, the expression of N-Cadheri and PMP22 proteins in the collagen/ORC-Ca composite scaffold is significantly superior to the other two scaffolds (both p < 0.01). Therefore, it could be concluded that the collagen/ORC-Ca composite is a promising candidate as a scaffold for carrying SC to form nerve tissue engineering composites in order to assist the peripheral nervous in the repair and regeneration.


Assuntos
Materiais Biocompatíveis/química , Cálcio/química , Celulose Oxidada/química , Colágeno/química , Portadores de Fármacos/química , Células de Schwann/citologia , Materiais Biocompatíveis/farmacologia , Caderinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Celulose Oxidada/farmacologia , Portadores de Fármacos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Fenômenos Mecânicos , Proteínas da Mielina/metabolismo , Nervos Periféricos/efeitos dos fármacos , Nervos Periféricos/fisiologia , Regeneração , Células de Schwann/química , Molhabilidade
14.
Int J Biol Macromol ; 94(Pt A): 466-473, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27771407

RESUMO

Antibacterial finishing of textiles has been introduced as a necessary process for various purposes especially creating a fabric with antimicrobial activities. Currently, the textile industry continues to look for textiles antimicrobial finishing process based on sustainable biopolymers from the viewpoints of environmental friendliness, industrialization, and economic concerns. This paper reviews the role of alginate, a sustainable biopolymer, in the development of antimicrobial textiles, including both basic physicochemical properties of alginate such as preparation, chemical structure, molecular weight, solubility, viscosity, and sol-gel transformation property. Then different processing routes (e.g. nanocomposite coating, ionic cross-linking coating, and Layer-by-Layer coating) for the antibacterial finishing of textiles by using alginate are revised in some detail. The achievements in this area have increased our knowledge of alginate application in the field of textile industry and promoted the development of green textile finishing.


Assuntos
Alginatos/química , Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Têxteis , Humanos , Ligação de Hidrogênio , Nanocompostos/química
15.
Mater Sci Eng C Mater Biol Appl ; 76: 130-138, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482498

RESUMO

In this study, polyanionic alginate gel beads crosslinked by Ca2+ and glutaraldehyde have demonstrated a strong electrostatic interaction with specific proteins. Due to the naturally abundant carboxyl groups, the prepared alginate gel beads exhibited a relatively superior integrated adsorption performance toward lysozyme, including a superior adsorption capacity of 213mgg-1, fast adsorption equilibrium within 12h, good selectivity, and good reversibility. Compared with other protein adsorbents, the as-prepared adsorptive beads have the advantages of excellent adsorption performance, easy to prepare, convenient, efficient, reliable and environment-friendly to apply, which can serve as a more sustainable material in protein separation and purification.


Assuntos
Muramidase/metabolismo , Adsorção , Alginatos , Polieletrólitos , Polímeros
16.
Carbohydr Polym ; 165: 30-38, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28363553

RESUMO

Sponges composed of different levels of composite collagen/oxidized microcrystalline cellulose (collagen/OMCC), denoted M1-M4, were studied to improve the hemostatic effect of single-collagen sponges. Surface morphological observations showed that structural combinations and intermolecular interactions occurred between collagen and OMCC in the composites. M2 presented the best physical properties and platelet activation and was thus selected for the investigations of the in vitro coagulation time and hemostatic and biological effects on animals. The results illustrated that M2 could reduce the length of the activated partial thromboplastin time (APTT) and thrombin time (TT) and presented rapid hemostatic efficiency in the two injury models (P<0.05). These findings were used to evaluate the hemostatic mechanism of M2, which can promote blood absorption and platelet activation and could be directly involved in the intrinsic coagulation pathway to accelerate hemostasis. Furthermore, M2 was not cytotoxic and was completely biodegraded in subcutaneous tissue within 28days.


Assuntos
Coagulação Sanguínea , Celulose/química , Colágeno/farmacologia , Hemostasia , Hemostáticos/farmacologia , Animais , Celulose Oxidada , Humanos , Tempo de Tromboplastina Parcial , Coelhos , Tempo de Trombina
17.
Chem Commun (Camb) ; 53(61): 8537-8540, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28707693

RESUMO

Multi-compartmentalized biphasic proteinosomes were self-assembled using a single-step double Pickering emulsion procedure, and exploited for enzyme-mediated interfacial catalysis, polysaccharide shell templating, and hydrogel functionalization.


Assuntos
Resinas Acrílicas/química , Células Artificiais/química , Nanoconjugados/química , Soroalbumina Bovina/química , Alginatos/química , Animais , Bovinos , Dextranos/química , Glucose/química , Glucose Oxidase/química , Hexanóis/química , Hidrogéis/química , Himecromona/análogos & derivados , Himecromona/química , Lipase/química , Água/química
18.
Biomater Sci ; 4(2): 272-80, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26484364

RESUMO

A well-defined core-shell nano-carrier (PAA-MHAPNs) was successfully synthesized based on a graft-onto method by using mesoporous hydroxyapatite nanoparticles (MHAPNs) as the core and polyacrylic acid (PAA) as the shell. Given that MHAPNs are regarded as one of the most promising drug delivery vehicles due to their excellent performance and the nature of their cancer cell anti-proliferative effect, and the grafted PAA, as a pH-responsive switch, could improve the loading amount of the drug doxorubicin hydrochloride (DOX) effectively by electrostatic interactions, all these advantages mean that the designed models show promise for application in pH-responsive drug delivery systems. The loading content and entrapment efficiency of DOX could reach up to 3.3% and 76%, respectively. The drug release levels of the constructed DOX@PAA-MHAPNs were low under normal physiological conditions (pH 7.4), but they could be increased significantly with a decrease of pH. Cytotoxicity assays indicated that the PAA-MHAPNs was biocompatible, and more importantly, the DOX@PAA-MHAPNs demonstrated an obvious ability to induce apoptosis of cancer cells. Overall, the synthesized systems should show great potential as drug nanovehicles with excellent biocompatibility, high drug loading, and pH-responsive features for future intracellular drug delivery.


Assuntos
Resinas Acrílicas/química , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos/efeitos dos fármacos , Durapatita/química , Nanopartículas/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Durapatita/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Porosidade
19.
Colloids Surf B Biointerfaces ; 145: 526-538, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27281238

RESUMO

A glycyrrhetinic acid-modified chitosan-cystamine-poly(ε-caprolactone) copolymer (PCL-SS-CTS-GA) micelle was developed for the co-delivery of doxorubicin (DOX) and curcumin (CCM) to hepatoma cells. Glycyrrhetinic acid (GA) was used as a targeting unit to ensure specific delivery. Co-encapsulation of DOX and CCM was facilitated by the incorporation of poly(ε-caprolactone) (PCL) groups. The highest drug loading content was 19.8% and 8.9% (w/w) for DOX and CCM, respectively. The PCL-SS-CTS-GA micelle presented a spherical or ellipsoidal geometry with a mean diameter of approximately 110nm. The surface charge of the micelle changed from negative to positive, when the pH value of the solution decreased from 7.4 to 6.8. Meanwhile, it also exhibited a character of redox-responsive drug release and GA/pH-mediated endocytosis in vitro. In simulated body fluid with 10mM glutathione, the release rate in 12h was 80.6% and 67.2% for DOX and CCM, respectively. The cell uptake of micelles was significantly higher at pH 6.8 than pH 7.4. The combined administration of DOX and CCM was facilitated by PCL-SS-CTS-GA micelle. Results showed that there was strong synergic effect between the two drugs. The PCL-SS-CTS-GA micelle might turn into a promising and effective carrier for improved combination chemotherapy.


Assuntos
Quitosana/química , Curcumina/farmacologia , Cistamina/química , Doxorrubicina/farmacologia , Ácido Glicirretínico/química , Micelas , Neoplasias/tratamento farmacológico , Poliésteres/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Espaço Intracelular/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Biomed Mater Eng ; 24(1): 651-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24211950

RESUMO

Sunscreens that absorb UV light without photodegradation could reduce skin cancer. Polyvinyl silsesquioxanes are known to have greater thermal and photochemical stability than organic compounds, such as those in sunscreens. This paper evaluates the UV transparency of vinyl silsesquioxanes (VS) and its hybrids with SiO2(VSTE) and TiO2(VSTT) experimentally and computationally. Based on films of VS prepared by sol-gel polymerization, using benzoyl peroxide as an initiator, vinyltrimethoxysilane (VMS) formulated oligomer through thermal curing. Similarly, VSTE films were prepared from VMS and 5-25 wt-% tetraethoxysilane (TEOS) and VSTT films were prepared from VMS and 5-25 wt-% titanium tetrabutoxide (TTB). Experimental average transparencies of the modified films were found to be about 9-14% between 280-320 nm, 67-73% between 320-350nm, and 86-89% between 350-400nm. Computation of the band gap was absorption edges for the hybrids in excellent agreement with experimental data. VS, VSTE and VSTT showed good absorption in UV-C and UV-B range, but absorbed virtually no UV-A. Addition of SiO2 or TiO2 does not improve UV-B absorption, but on the opposite increases transparency of thin films to UV. This increase was validated with molecular simulations. Results show computational design can predict better sunscreens and reduce the effort of creating sunscreens that are capable of absorbing more UV-B and UV-A.


Assuntos
Compostos de Organossilício/química , Polivinil/química , Silanos/química , Dióxido de Silício/química , Protetores Solares/química , Titânio/química , Absorção , Adsorção , Algoritmos , Peróxido de Benzoíla/química , Butanóis/química , Simulação por Computador , Bases de Dados Factuais , Radicais Livres , Géis , Hidrólise , Teste de Materiais , Compostos Organometálicos/química , Transição de Fase , Reprodutibilidade dos Testes , Software , Solventes/química , Raios Ultravioleta
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