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1.
J Agric Food Chem ; 68(10): 3050-3060, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32069040

RESUMO

Industrial wastewater has brought great disaster to water bodies and soils and seriously affected the growth of crops. It is necessary to prepare a stable, effective, and sustainable treatment agent to control water pollution to obtain clean water. The adsorption effect of a lignosulfonate-lysine hydrogel (CLS-Lys adsorbent) on heavy metal ions (Cu2+ and Co2+) in water is studied. In the synthesis experiment, a response surface method is used to optimize the content of sodium lignosulfonate, lysine, initiator, and cross-linker. The CLS-Lys adsorbent is characterized by Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, thermal analysis, and zeta potential analysis. The performance of the CLS-Lys adsorbent under different influencing factors is studied. The kinetic and isothermal models of the CLS-Lys adsorbent are established. The results show that the main adsorption model of the CLS-Lys adsorbent is chemical adsorption, accompanied by electrostatic adsorption. These two ions have a competitive adsorption relationship, and when the two ions are present at the same time, they inhibit each other. In addition, the CLS-Lys adsorbent has good adsorption and analytical regeneration performance. It is an economic and effective adsorbent and has a broad application prospect.


Assuntos
Hidrogéis/química , Lignina/análogos & derivados , Lisina/química , Metais Pesados/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Hidrogéis/síntese química , Cinética , Lignina/química , Águas Residuárias/química , Purificação da Água/instrumentação
2.
Chem Commun (Camb) ; 56(7): 1085-1088, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31894779

RESUMO

We report an elastase-responsive, H2S-releasing hydrogel prepared by covalently crosslinking a mixture of carboxymethylcellulose and poly(ethylene glycol) with an elastase-degradable peptide functionalized with an H2S-releasing S-aroylthiooxime (SATO) unit. Addition of elastase triggered a gel-to-sol transition, which exposed SATOs, leading to more and longer H2S release compared to untriggered gels.


Assuntos
Carboximetilcelulose Sódica/farmacologia , Hidrogéis/farmacologia , Sulfeto de Hidrogênio/metabolismo , Elastase de Leucócito/metabolismo , Polietilenoglicóis/farmacologia , Animais , Carboximetilcelulose Sódica/síntese química , Carboximetilcelulose Sódica/metabolismo , Linhagem Celular , Doxorrubicina/toxicidade , Humanos , Hidrogéis/síntese química , Hidrogéis/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oximas/síntese química , Oximas/metabolismo , Oximas/farmacologia , Polietilenoglicóis/síntese química , Polietilenoglicóis/metabolismo , Substâncias Protetoras/síntese química , Substâncias Protetoras/metabolismo , Substâncias Protetoras/farmacologia , Ratos
3.
Mater Sci Eng C Mater Biol Appl ; 107: 110219, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761177

RESUMO

Silver nanoparticles (AgNPs) and regenerated silk fibroin (RSF) have recently attracted significant interests for their potential applications in preventing wound-related infections and in tissue engineering. Indeed, nano-silver has long been recognized as one of the most effective antimicrobial agents, and silk fibroin is well known for its capability of stimulating cell activities and facilitating tissue regeneration. In this study, a green synthesis approach was used to create a composite hydrogel (CoHy) of RSF stabilized with CarboxymethylCellulose-Na (CMC-Na) and loaded with AgNPs. Their swelling ratios were up to 59 g/g when tested in different physiologically relevant fluids. Material characterizations by Scanning electron microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS), and X-Ray Diffraction (XRD) confirmed the presence of AgNPs on the surface. Antimicrobial properties of the CoHy samples were evaluated using agar diffusion tests. The results showed distinct inhibition zones against major microorganisms found in wound infections, including Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), Methicillin Resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa (P. aeruginosa), Candida albicans (C. albicans) and Fluconazole-resistant Candida albicans (FRCA). Cytocompatibility studies with rat bone marrow derived mesenchymal stem cells (BMSCs) in vitro showed that the adhesion density of BMScs on the CoHy loaded with 1 mg/mL was similar to the cell-only control group for the first 24 h of culture; moreover, higher cell proliferation was observed on the CoHy without AgNPs, indicating the regenerative potentials of the RSF/CMC composite hydrogels.


Assuntos
Carboximetilcelulose Sódica/química , Fibroínas/química , Hidrogéis/química , Nanocompostos/química , Prata/química , Raios Ultravioleta , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Hidrogéis/síntese química , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Testes de Sensibilidade Microbiana , Ratos
4.
Chem Asian J ; 14(24): 4837-4846, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31756283

RESUMO

Three-dimensional (3D) scaffolds formed from natural biopolymers gelatin and chitosan that are chemically modified by galactose have shown improved hepatocyte adhesion, spheroid geometry and functions of the hepatocytes. Galactose specifically binds to the hepatocytes via the asialoglycoprotein receptor (ASGPR) and an increase in galactose density further improves the hepatocyte proliferation and functions. In this work, we aimed to increase the galactose density within the biopolymeric scaffold by physically blending the biopolymers chitosan and gelatin with an amphiphlic ß-galactose polypeptide (PPO-GP). PPO-GP, is a di-block copolymer with PPO and ß-galactose polypeptide, exhibits lower critical solution temperature and is entrapped within the scaffold through hydrophobic interactions. The uniform distribution of PPO-GP within the scaffold was confirmed by fluorescence microscopy. SEM and mechanical testing of the hybrid scaffolds indicated pore size, inter connectivity and compression modulus similar to the scaffolds made from 100 % biopolymer. The presence of the PPO-GP on the surface of the scaffold was tested monitoring the interaction of an analogous mannose containing PPO-GP scaffold and the mannose binding lectin Con-A. In vitro cell culture experiments with HepG2 cells were performed on GLN-GP and CTS-GP and their cellular response was compared with GLN and CTS scaffolds for a period of seven days. Within three days of culture the Hep G2 cells formed multicellular spheroids on GLN-GP and CTS-GP more efficiently than on the GLN and CTS scaffolds. The multicellular spheroids were also found to infiltrate more in GLN-GP and CTS-GP scaffolds and able to maintain their round morphology as observed by live/dead and SEM imaging.


Assuntos
Quitosana/química , Gelatina/química , Glicoproteínas/química , Hepatócitos/metabolismo , Polímeros/química , Propilenoglicóis/química , Tecidos Suporte/química , Animais , Módulo de Elasticidade , Galactosídeos/química , Células Hep G2 , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Esferoides Celulares/metabolismo , Suínos , Engenharia Tecidual/métodos
5.
Chem Commun (Camb) ; 55(87): 13112-13115, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31612874

RESUMO

Biocompatible chemical cross-linked hybrid polyethylene glycol-based hydrogels were obtained from a sol-gel process using bis-silylated molecular precursors in biocompatible conditions. This soft procedure (pH = 7.4, at 25 °C), allows the production of microgels by microfluidics and easy encapsulation of a model protein (Bovin Serum Albumine, BSA).


Assuntos
Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Microfluídica , Polietilenoglicóis/síntese química , Soroalbumina Bovina/química , Animais , Materiais Biocompatíveis/química , Bovinos , Géis/química , Hidrogéis/química , Estrutura Molecular , Tamanho da Partícula , Polietilenoglicóis/química , Propriedades de Superfície
6.
Int J Nanomedicine ; 14: 6901-6915, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564860

RESUMO

Background: Smart materials capable of responding to external stimuli are noteworthy candidates in designing drug delivery systems. In many of the recent research, temperature and pH have been recognized as the main stimulating factors in designing systems for anti-cancer drugs delivery systems. Purpose: In this study, thermo and pH-responsive character of a nano-carrier drug delivery platform based on lysine modified poly (vinylcaprolactam) hydrogel conjugated with doxorubicin was assessed. Methods: Poly (vinylcaprolactam) cross-linked with poly (ethyleneglycol) diacrylate was prepared via RAFT polymerization, and the prepared structure was linked with lysine through ring-opening. The anti-cancer drug doxorubicin, was linked to lysine moiety of the prepared structure via Schiff-base reaction. The prepared platform was characterized by 1HNMR and FT-IR, while molecular weight characterization was performed by size exclusion chromatography. The temperature-responsive activity was evaluated using differential scanning calorimetry and dynamic light scattering. In vitro release pattern in simulated physiologic pH at 37°C was compared with acidic pH attributed to tumor site and elevated temperature. The anticancer efficiency of the drug-conjugated structure was evaluated in breast cancer cell line MCF-7 in 24 and 48 h, and cell uptake assay was performed on the same cell line. Conclusion: According to the results, well-structure defined smart pH and temperature responsive nano-hydrogel was prepared. The enhanced release rates are observed at acidic pH and elevated temperature. We have concluded that the doxorubicin-conjugated nanoparticle results in higher cellular uptakes and more cytotoxicity.


Assuntos
Caprolactama/análogos & derivados , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Lisina/química , Nanopartículas/química , Polímeros/química , Temperatura , Caprolactama/síntese química , Caprolactama/química , Morte Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Células MCF-7 , Peso Molecular , Nanopartículas/ultraestrutura , Transição de Fase , Polímeros/síntese química , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Toxicidade
7.
Nat Commun ; 10(1): 4774, 2019 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636256

RESUMO

Constitutional dynamic networks (CDNs) attract interest as signal-triggered reconfigurable systems mimicking natural networks. The application of CDNs to control material properties is, however, a major challenge. Here we report on the design of a CDN consisting of four toehold-modified constituents, two of which act as bidentate units for chain-elongating, while the other two form a tetradentate structure acting as a crosslinking unit. Their hybridization yields a hydrogel of medium stiffness controlled by the balance between bidentate and tetradentate units. Stabilization of the tetradentate constituent by an auxiliary effector up-regulates the crosslinking unit, yielding a high-stiffness hydrogel. Conversely, stabilization of one of the bidentate constituents by an orthogonal effector enriches the chain-elongation units leading to a low-stiffness hydrogel. Using appropriate counter effectors, the hydrogels are reversibly switched across low-, medium- and high-stiffness states. The hydrogels are used to develop self-healing and controlled drug-release matrices and functional materials for operating biocatalytic cascades.


Assuntos
DNA/química , Módulo de Elasticidade , Hidrogéis/síntese química , Ciência dos Materiais , Biocatálise , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Elasticidade , Teste de Materiais
8.
Soft Matter ; 15(37): 7381-7389, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31513229

RESUMO

Two block copolymers containing two amino-acid derivatives, PEO-b-PLAA and PEO-b-PAAC, were fabricated through atom transfer radical polymerization (ATRP) or reversible addition-fragmentation chain transfer polymerization (RAFT). Then, they were employed as a macro-crosslinker to prepare high-performance poly(acrylic acid) (PAA) hydrogels named "PxAy" or "TyAz". There were numerous synergistic noncovalent interactions with hydrogen bonds between the macro-crosslinker and PAA chains, as well as entanglement of polymer chains. Hence, the hydrogels exhibited desirable mechanical properties and self-healing abilities. For PxAy hydrogels, the maximum fracture elongation and fracture strength were 9800% and 120.01 kPa, respectively. Moreover, the enhanced physical interaction enabled the hydrogels to have rapid self-healing abilities without stimulation. The hydrogels showed >80% self-healing efficiency and exhibited ∼10-3 S cm-1 electrical conductivity upon the introduction of KCl. Meanwhile, benefitting from doubling the number of carboxyl groups in the macro-crosslinker of the TyAz hydrogels compared with the PxAy hydrogels, the mechanical properties of TyAz hydrogels could be promoted further and notch-insensitivity could be observed. Tough, adhesive, self-healable, and conductive PAA hydrogels with different structures of amino-acid derivatives could aid the development of macro-crosslinkers.


Assuntos
Resinas Acrílicas/química , Ácido Aspártico/análogos & derivados , Hidrogéis/síntese química , Leucina/análogos & derivados , Polietilenoglicóis/química
9.
Mater Sci Eng C Mater Biol Appl ; 104: 109845, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500034

RESUMO

The facile preparation of macroporous, super water absorbing, biocompatible hydrogels of chitosan involving the hydrothermal reaction of a mixture of chitosan (CH), succinic acid (SA) and urea (UR), all of which are sustainable materials, is reported. The structure of the dry CHSAUR was ascertained by CP MAS-SS NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, powder x-ray diffraction analysis (PXRD), and thermogravimetric analysis (TGA). The principle role of UR in the synthesis was identified as the source of ammonia, which increased the pH of the acidic chitosan solution with reaction time, leading to the formation of the insoluble hydrogel of chitosan accompanied by the formation of pores of different sizes and volumes. In addition, a small fraction of urea participated in chemical reaction with the primary hydroxyl groups in the sixth position of the glucosamine repeat units of chitosan resulting in carbamate linkages. The as-prepared hydrogel, following workup and methanol extraction, was found to be chitosan crosslinked with succinic acid through electrostatic interaction. It was macroporous with percentage porosity varying between 49.4% to 64.2%. It also exhibited different extents of water uptake with the maximum of 760 ±â€¯20 g/g being for the one prepared with the weight ratio of 1: 4: 4 of chitosan: succinic acid: urea. The absorption of water is found to arise out of the porosity as well as presence of water attracting chitosan ammonium cation-succinate electrovalent bonds that are formed by the reaction between SA and ammonium cation of the chitosan backbone. The absorption of saline water was relatively poor suggesting that the saline water absorption might be arising largely due to the presence of micropores and specific interaction. The hydrogels exhibited Herschel-Bulkley rheological behavior. The extraction of CHSAUR with 0.1 N NaOH in methanol resulted in the removal of the physical crosslinks, consisting of succinate anions; the presence of chitosan with porous morphology was confirmed additionally by copper (+2) adsorption. In contrast to the widely reported method of preparing microporous chitosan scaffold of cylindrical shape that takes several days to a week, the present method offers a simple means of preparing macroporous chitosan of any shape and size in very large scale with soft foam-like morphology. With its biocompatibility towards mouse fibroblast cells it could find applications in drug delivery, biodegradable super water absorbency and haemostatic applications.


Assuntos
Materiais Biocompatíveis/síntese química , Quitosana/química , Hidrogéis/síntese química , Temperatura , Ureia/química , Água/química , Células 3T3-L1 , Animais , Sobrevivência Celular , Reagentes para Ligações Cruzadas/química , Hidrogéis/química , Espectroscopia de Ressonância Magnética , Camundongos , Porosidade , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Viscosidade , Difração de Raios X , Microtomografia por Raio-X
10.
J Mater Sci Mater Med ; 30(9): 102, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31485761

RESUMO

Dysfunction of the corneal endothelium (CE) resulting from progressive cell loss leads to corneal oedema and significant visual impairment. Current treatments rely upon donor allogeneic tissue to replace the damaged CE. A donor cornea shortage necessitates the development of biomaterials, enabling in vitro expansion of corneal endothelial cells (CECs). This study investigated the use of a synthetic peptide hydrogel using poly-ε-lysine (pεK), cross-linked with octanedioic-acid as a potential substrate for CECs expansion and CE grafts. PεK hydrogel properties were optimised to produce a substrate which was thin, transparent, porous and robust. A human corneal endothelial cell line (HCEC-12) attached and grew on pεK hydrogels as confluent monolayers after 7 days, whereas primary porcine CECs (pCECs) detached from the pεK hydrogel. Pre-adsorption of collagen I, collagen IV and fibronectin to the pεK hydrogel increased pCEC adhesion at 24 h and confluent monolayers formed at 7 days. Minimal cell adhesion was observed with pre-adsorbed laminin, chondroitin sulphate or commercial FNC coating mix (fibronectin, collagen and albumin). Functionalisation of the pεK hydrogel with synthetic cell binding peptide H-Gly-Gly-Arg-Gly-Asp-Gly-Gly-OH (RGD) or α2ß1 integrin recognition sequence H-Asp-Gly-Glu-Ala-OH (DGEA) resulted in enhanced pCEC adhesion with the RGD peptide only. pCECs grown in culture at 5 weeks on RGD pεK hydrogels showed zonula occludins 1 staining for tight junctions and expression of sodium-potassium adenosine triphosphase, suggesting a functional CE. These results demonstrate the pεK hydrogel can be tailored through covalent binding of RGD to provide a surface for CEC attachment and growth. Thus, providing a synthetic substrate with a therapeutic application for the expansion of allogenic CECs and replacement of damaged CE.


Assuntos
Proliferação de Células , Transplante de Córnea , Células Endoteliais/fisiologia , Epitélio Posterior/transplante , Hidrogéis/síntese química , Polilisina/química , Tecidos Suporte/química , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Transplante de Córnea/métodos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Epitélio Posterior/citologia , Epitélio Posterior/fisiologia , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Teste de Materiais , Polilisina/farmacologia , Suínos
11.
AAPS PharmSciTech ; 20(7): 297, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444661

RESUMO

Miconazole nitrate (MZ) is a BCS class II antifungal poorly water-soluble drug with limited dissolution properties and gastrointestinal side effects. Self-nanoemulsifying delivery system-based gel of MZ can improve both solubility and oral mucosal absorption with enhanced antifungal activity. The study aims to formulate MZ self-nanoemulsion (MZ-NE) and combine it within hyaluronic acid-based gel. MZ solubility in various oils, surfactants, and cosurfactant used in NE formulations were evaluated. Mixture design was implemented to optimize the levels of NE components as a formulation variable to study their effects on the mean globule size and antifungal inhibition zones. Further, the optimized MZ-NE was loaded into a hyaluronic acid gel base. Rheological behavior of the prepared gel was assessed. Ex vivo permeability of optimized formulation across buccal mucous of sheep and inhibition against Candida albicans were examined. Mixture design was used to optimize the composition of MZ-NE formulation as 22, 67, and 10% for clove oil, Labrasol, and propylene glycol, respectively. The optimized formulation indicated globule size of 113 nm with 29 mm inhibition zone. Pseudoplastic flow with thixotropic behavior was observed, which is desirable for oral gels. The optimized formulation exhibited higher ex vivo skin permeability and enhanced antifungal activity by 1.85 and 2.179, respectively, compared to MZ-SNEDDS, and by 1.52 and 1.72 folds, respectively, compared to marketed gel. Optimized MZ-NE hyaluronic acid-based oral gel demonstrated better antifungal activity, indicating its potential in oral thrush pharmacotherapy.


Assuntos
Antifúngicos/administração & dosagem , Candidíase Bucal/tratamento farmacológico , Química Farmacêutica/métodos , Ácido Hialurônico/administração & dosagem , Miconazol/administração & dosagem , Nanocápsulas/administração & dosagem , Administração Oral , Animais , Antifúngicos/síntese química , Antifúngicos/farmacocinética , Candidíase Bucal/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Emulsões/administração & dosagem , Emulsões/síntese química , Emulsões/farmacocinética , Ácido Hialurônico/síntese química , Ácido Hialurônico/farmacocinética , Hidrogéis/administração & dosagem , Hidrogéis/síntese química , Hidrogéis/farmacocinética , Miconazol/síntese química , Miconazol/farmacocinética , Nanocápsulas/química , Ovinos
12.
Carbohydr Polym ; 223: 115062, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426967

RESUMO

Nata de coco was chemically modified to afford the bacterial cellulose hydrogels carrying terminal alkynes. The resultant hydrogels were then converted into hydrogels carrying lactosides or those carrying α-2,3-sialyllactosides by the Cu+-catalyzed alkyne-azide cyclization. The stable homo association of the hydrogels carrying lactosides was observed in an aqueous solution containing Ca2+, thereby demonstrating the Ca2+-mediated lactoside-lactoside interactions. Ca2+ also stabilized the hetero associations among the hydrogels carrying lactosides and those carrying α-2,3-sialyllactosides, thereby also demonstrating the Ca2+-induced interactions between the lactosides and the α-2,3-sialyllactosides. The sizes of these hydrogels were of the order of ca. 5 mm, and their associations could thus be readily monitored with the naked eye.


Assuntos
Celulose/química , Hidrogéis/química , Oligossacarídeos/química , Polissacarídeos Bacterianos/química , Alquinos/química , Azidas/química , Cálcio/química , Cocos/química , Cocos/microbiologia , Hidrogéis/síntese química , Magnésio/química , Lectinas de Plantas/química , Ricinus/química , Sódio/química
13.
Carbohydr Polym ; 223: 115059, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426985

RESUMO

Fast-swelling, porous cellulose hydrogels (PCHs) were generated via simple acid treatment of cellulose hydrogel prepared in NaOH/urea medium. Structural characteristics of the PCHs were investigated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Swelling behavior was assessed by measuring the swelling kinetics in deionized water. Mechanical properties were also examined. The results showed that acid treated PCHs had many more micropores, mesopores and macropores, and PCH-6% displayed a high specific surface area of 33.98 m2/g. However, cellulose hydrogel without acid treatment had a low specific surface area (2.499 m2/g). Mechanical property of hydrogel was found to be slightly deteriorated with the improvement of porous structure. The equilibrium swelling rate of PCHs had drastically improvement after acid treatment. This porous cellulose hydrogel skeleton presents a wide range of possibilities for the further development of fast swelling cellulose-based functional hydrogel.


Assuntos
Celulose/química , Hidrogéis/química , Ureia/química , Ácido Acético/química , Força Compressiva , Epicloroidrina/química , Linho/química , Hidrogéis/síntese química , Porosidade
14.
Carbohydr Polym ; 223: 115023, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31427021

RESUMO

The wounds closure after physical injury or surgery is of significant clinical and research importance. In this study, thermosensitive and injectable hydrogels based on hyaluronic acid (HA), corn silk extract (CSE) and nanosilver were prepared and their potential use as a wound care material was investigated. Silver nanoparticles (Ag NPs) were biosynthesized by a microwave-assisted green technique using corn silk extract in an organic solvent-free medium. Rheological analysis demonstrated that the nanocomposites have good mechanical properties with gelation temperature close to the body temperature; hence, they can be easily administrated locally on wounded skins. The samples exhibited antibacterial activity toward gram-positive and gram-negative bacteria. Cytotoxicity assay showed that the hydrogels have good biocompatibility. Interestingly, an in-vitro model of wound healing revealed that the nanocomposites allow faster wound closure and repair, compared to the control. The obtained results highlight the potential application of these novel injectable hydrogels as wound dressing.


Assuntos
Antibacterianos/farmacologia , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Animais , Antibacterianos/síntese química , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Hidrogéis/síntese química , Camundongos , Testes de Sensibilidade Microbiana , Nanocompostos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Zea mays/química
15.
Carbohydr Polym ; 223: 115070, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31427031

RESUMO

A biodegradable, near-infrared (NIR) - responsive hydrogel is one of the most promising strategies as a remotely triggered drug carrier. In this study, novel NIR-responsive hydrogels based on alginate structures were prepared for controllable drug release. The hydrogels were formed rapidly by reacting norbornene-functionalized alginates and tetrazine cross-linkers containing diselenide bonds via inverse electron demand Diels-Alder click chemistry. In order to manipulate their properties, we prepared hydrogels with various cross-linking densities. NIR sensitive indocyanine green (ICG) and a drug, doxorubicin (DOX) were incorporated in the hydrogel matrix during gelation. The hydrogels showed a suppressed release profile under physiological conditions, while NIR light triggered a rapid release of DOX. Under NIR-light irradiation, ICG generated reactive oxygen species which could decompose diselenide bonds in the hydrogel matrix, inducing the gel-sol transition and release of entrapped DOX. The degradation of hydrogels could be also controlled by the ratio of the precursors.


Assuntos
Alginatos/química , Portadores de Fármacos/química , Hidrogéis/química , Compostos Organosselênicos/química , Alginatos/síntese química , Alginatos/efeitos da radiação , Doxorrubicina/química , Portadores de Fármacos/efeitos da radiação , Liberação Controlada de Fármacos , Compostos Heterocíclicos com 1 Anel/síntese química , Compostos Heterocíclicos com 1 Anel/química , Compostos Heterocíclicos com 1 Anel/efeitos da radiação , Hidrogéis/síntese química , Hidrogéis/efeitos da radiação , Peróxido de Hidrogênio/química , Raios Infravermelhos , Norbornanos/síntese química , Norbornanos/química , Norbornanos/efeitos da radiação , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/efeitos da radiação
16.
ACS Appl Mater Interfaces ; 11(38): 34766-34776, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31429547

RESUMO

The construction of polymeric nanocomponents into a hierarchical structure poses great importance for subsequent biomedical applications. Herein, we report for the first time the electroassembly of chitin nanoparticles (14 nm ± 3 nm from transmission electron microscopy) to construct thick and freestanding hydrogels, which can be further dried to obtain high porous and tough aerogels for wound healing. The electroassembly is a simple, straightforward, and controllable process, which crucially depends on the pH of the chitin nanoparticle suspension and the degree of deacetylation of chitin. Interestingly, the electroassembly of chitin nanoparticles is completely reversible, suggesting the physical assembly feature of the freestanding hydrogel. By using supercritical CO2 drying and freeze-drying, chitin aerogels and cryogels can be facilely obtained. Because of the intriguing features (i.e., large surface area, interconnected porous structure, and enhanced hydrophilicity), chitin aerogels demonstrate adorable performance to accelerate the healing of wounds.


Assuntos
Quitina , Técnicas Eletroquímicas , Hidrogéis , Nanopartículas , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Animais , Linhagem Celular , Quitina/química , Quitina/farmacologia , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
17.
Sensors (Basel) ; 19(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408931

RESUMO

Conceptual and commercial examples of implantable sensors have been limited to a relatively small number of target analytes, with a strong focus on glucose monitoring. Recently, surface-enhanced Raman spectroscopy (SERS) pH sensors were demonstrated to track acid-producing enzymatic reactions targeting specific analytes. We show here that SERS pH tracking in the basic regime is also possible, and can be used to monitor urea concentration. To accomplish this, we developed a hydrogel consisting of polyelectrolyte multilayer microcapsules containing a SERS-sensitive pH reporter (4-mercapopyridine capped silver nanoparticles modified with bovine serum albumin). This pH sensing material exhibited a sensitive Raman scattering response to a wide range of pH from 6.5-9.7. By incorporating urease into the hydrogel matrix, the new sensor was capable of distinguishing urea concentrations of 0, 0.1, 1, and 10 mM. We also found that bovine serum albumin (BSA) prevented severe aggregation of the nanoparticle-based pH sensor, which improved sensing range and sensitivity. Furthermore, BSA safeguarded the pH sensor during the encapsulation procedure. Together, the combination of materials represents a novel approach to enabling optical sensing of reactions that generate pH changes in the basic range.


Assuntos
Hidrogéis/química , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos , Ureia/análise , Animais , Cápsulas/química , Bovinos , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Polieletrólitos/química , Coroa de Proteína/química , Soroalbumina Bovina/química
18.
ACS Appl Mater Interfaces ; 11(28): 24984-24998, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264830

RESUMO

The aim of this study was to design a click-crosslinked hyaluronic acid (HA) (Cx-HA) depot via a click crosslinking reaction between tetrazine-modified HA and trans-cyclooctene-modified HA for direct intra-articular injection into joints affected by rheumatoid arthritis (RA). The Cx-HA depot had significantly more hydrogel-like features and a longer in vivo residence time than the HA depot. Methotrexate (MTX)-loaded Cx-HA (MTX-Cx-HA)-easily prepared as an injectable formulation-quickly formed an MTX-Cx-HA depot that persisted at the injection site for an extended period. In vivo MTX biodistribution in MTX-Cx-HA depots showed that a high concentration of MTX persisted at the intra-articular injection site for an extended period, with little distribution of MTX to normal tissues. In contrast, direct intra-articular injection of MTX alone or MTX-HA resulted in rapid clearance from the injection site. After intra-articular injection of MTX-Cx-HA into rats with RA, we noted the most significant RA reversal, measured by an articular index score, increased cartilage thickness, extensive generation of chondrocytes and glycosaminoglycan deposits, extensive new bone formation in the RA region, and suppression of tumor necrosis factor-α or interleukin-6 expression. Therefore, MTX-Cx-HA injected intra-articularly persists at the joint site in therapeutic MTX concentrations for an extended period, thus increasing the duration of RA treatment, resulting in an improved relief of RA.


Assuntos
Artrite Reumatoide , Condrócitos , Hidrogéis , Articulações , Metotrexato , Animais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Condrócitos/metabolismo , Condrócitos/patologia , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Glicosaminoglicanos/metabolismo , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Injeções Intra-Articulares , Interleucina-6/metabolismo , Articulações/metabolismo , Articulações/patologia , Masculino , Metotrexato/química , Metotrexato/farmacocinética , Metotrexato/farmacologia , Camundongos , Células RAW 264.7 , Ratos , Distribuição Tecidual , Fator de Necrose Tumoral alfa/metabolismo
19.
J Microbiol Biotechnol ; 29(7): 1078-1082, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31280528

RESUMO

Poly-γ-glutamate (γ-PGA) has various applications due to its desirable characteristics in terms of safety and biodegradability. Previous studies have been conducted on γ-PGA hydrogels produced by γ-ray irradiation, but these hydrogels have proved unstable in solutions. This study was conducted to enable the γ-PGA hydrogel to maintain a stable form in solutions. The γ-PGA mixture for UV-irradiation was prepared with a cross-linker (N,N,N-trimethyl-3-[(2- methylacryloyl)amino]propan-1-aminium). Both γ-PGA hydrogels' characteristics, including stability in solutions, were examined. The UV-irradiated γ-PGA hydrogel maintained a stable form during the nine weeks of the study, but the γ-ray irradiated hydrogel dissolved after one week.


Assuntos
Raios gama , Hidrogéis/química , Ácido Poliglutâmico/análogos & derivados , Raios Ultravioleta , Materiais Biocompatíveis/química , Reagentes para Ligações Cruzadas/química , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Ácido Poliglutâmico/química , Soluções , Viscosidade
20.
Carbohydr Polym ; 222: 115011, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320040

RESUMO

Conventional agaroses with high gelling temperature are limited to apply to the field of drug delivery. In this study, ß-cyclodextrin (ßCD) functionalized agarose (CFA) with low gelling temperature was successfully prepared from ethylenediamine-functionalized agarose using mono-succinyl ßCD. The gelling temperature of CFA dramatically decreased to 26.7 °C from 65 °C and the melting temperature declined from 95 °C to 66.1 °C. Upon drug loading, CFA can be used at 30 °C because of its low gelling temperature compared to agarose. CFA gel could be used both for bovine serum albumin as a full release, and for the doxorubicin (DOX) for sustained release, via inclusion complexation of ßCD. Furthermore, cytotoxicity tests revealed that CFA was noncytotoxic. DOX in the CFA gel could retain the anti-cancer activity. Newly synthesized CFA with low gelling temperature offer a new means for the development of hydrogel-based delivery systems for a variety of therapeutic drugs.


Assuntos
Portadores de Fármacos/química , Hidrogéis/química , Sefarose/química , beta-Ciclodextrinas/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Bovinos , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Células HEK293 , Células HeLa , Humanos , Hidrogéis/síntese química , Hidrogéis/toxicidade , Sefarose/síntese química , Sefarose/toxicidade , Soroalbumina Bovina/química , Temperatura de Transição , beta-Ciclodextrinas/síntese química , beta-Ciclodextrinas/toxicidade
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