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1.
Biomacromolecules ; 25(5): 2990-3000, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38696732

RESUMO

Recently, we reported the synthesis of a hydrophilic aldehyde-functional methacrylic polymer (Angew. Chem., 2021, 60, 12032-12037). Herein we demonstrate that such polymers can be reacted with arginine in aqueous solution to produce arginine-functional methacrylic polymers without recourse to protecting group chemistry. Careful control of the solution pH is essential to ensure regioselective imine bond formation; subsequent reductive amination leads to a hydrolytically stable amide linkage. This new protocol was used to prepare a series of arginine-functionalized diblock copolymer nanoparticles of varying size via polymerization-induced self-assembly in aqueous media. Adsorption of these cationic nanoparticles onto silica was monitored using a quartz crystal microbalance. Strong electrostatic adsorption occurred at pH 7 (Γ = 14.7 mg m-2), whereas much weaker adsorption occurred at pH 3 (Γ = 1.9 mg m-2). These findings were corroborated by electron microscopy, which indicated a surface coverage of 42% at pH 7 but only 5% at pH 3.


Assuntos
Arginina , Nanopartículas , Nanopartículas/química , Adsorção , Arginina/química , Concentração de Íons de Hidrogênio , Polimerização , Dióxido de Silício/química , Polímeros/química , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/síntese química
2.
Macromol Rapid Commun ; 45(15): e2400141, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38695257

RESUMO

Reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization of methyl methacrylate (MMA) is successfully performed in water in the presence of a poly(methacrylic acid) (PMAA) macromolecular chain transfer agent (macroCTA) leading to the formation of self-stabilized PMAA-b-PMMA amphiphilic block copolymer particles. At pH 3.7, the reactions are well-controlled with narrow molar mass distributions. Increasing the initial pH, particularly above 5.6, results in a partial loss of reactivity of the PMAA macroCTA. The effect of the degree of polymerization (DPn) of the PMMA block, the solids content, the nature of the hydrophobic segment, and the pH on the morphology of the obtained diblock copolymer particles is then investigated. Worm-like micelles are formed for a DPn of PMMA of 20 (PMMA20), while "onion-like" particles and spherical vesicles are obtained for PMMA30 and PMMA50, respectively. In contrast, spherical particles are obtained for the DPns higher than 150. This unusual evolution of particle morphologies upon increasing the DPn of the PMMA block seems to be related to hydrogen bonds between hydrophilic MAA and hydrophobic MMA units.


Assuntos
Emulsões , Metilmetacrilato , Polimerização , Ácidos Polimetacrílicos , Emulsões/química , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/síntese química , Metilmetacrilato/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Interações Hidrofóbicas e Hidrofílicas , Polimetil Metacrilato/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Estrutura Molecular , Micelas
3.
Molecules ; 27(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35164104

RESUMO

Coffee, the most popular beverage in the 21st century society, was tested as a reaction environment for activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) without an additional reducing agent. Two blends were selected: pure Arabica beans and a proportional blend of Arabica and Robusta beans. The use of the solution received from the mixture with Robusta obtained a high molecular weight polymer product in a short time while maintaining a controlled structure of the synthesized product. Various monomers with hydrophilic characteristics, i.e., 2-(dimethylamino)ethyl methacrylate (DMAEMA), oligo(ethylene glycol) methyl ether methacrylate (OEGMA500), and glycidyl methacrylate (GMA), were polymerized. The proposed concept was carried out at different concentrations of coffee grounds, followed by the determination of the molar concentration of caffeine in applied beverages using DPV and HPLC techniques.


Assuntos
Café/química , Metacrilatos/química , Polimerização , Ácidos Polimetacrílicos , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química
4.
J Am Chem Soc ; 143(49): 20927-20938, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34855390

RESUMO

Timely lysosome escape is of paramount importance for endocytosed nanomedicines to avoid premature degradation under the acidic and hydrolytic conditions in lysosomes. Herein, we report an exciting finding that phenylboronic acid (PBA) modification can greatly facilitate the lysosome escape of cylindrical polymer brushes (CPBs). On the basis of our experimental results, we speculate that the mechanism is associated with the specific interactions of the PBA groups with lysosomal membrane proteins and hot shock proteins. The featured advantage of the PBA modification over the known lysosome escape strategies is that it does not cause significant adverse effects on the properties of the CPBs; on the contrary, it enhances remarkably their tumor accumulation and penetration. Furthermore, doxorubicin was conjugated to the PBA-modified CPBs with a drug loading content larger than 20%. This CPBs-based prodrug could eradicate the tumors established in mice by multiple intravenous administrations. This work provides a novel strategy for facilitating the lysosome escape of nanomaterials and demonstrates that PBA modification is an effective way to improve the overall properties of nanomedicines including the tumor therapeutic efficacy.


Assuntos
Antineoplásicos/uso terapêutico , Ácidos Borônicos/química , Portadores de Fármacos/química , Lisossomos/metabolismo , Neoplasias/tratamento farmacológico , Ácidos Polimetacrílicos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácidos Borônicos/síntese química , Ácidos Borônicos/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos Endogâmicos ICR , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/metabolismo , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico
5.
AAPS PharmSciTech ; 22(5): 182, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129146

RESUMO

The oral bioavailability of curcumin is limited, attributed to its low solubility or dissolution and poor absorption. Herein, the study describes formulation of curcumin-loaded mixed micelles of Gelucire® 48/16 and TPGS for its dissolution rate enhancement. Curcumin was dispersed in these molten lipidic surfactants which was then adsorbed on carrier and formulated as pellets by extrusion spheronization. Critical micelle concentration (CMC) of binary mixture of Gelucire® 48/16 and TPGS was lower than their individual CMC demonstrating the synergistic behavior of mixture. Thermodynamic parameters like partition coefficient and Gibbs free energy of solubilization indicated that mixed micelles were more efficient than micelles of its individual components in curcumin solubilization. Dynamic light scattering (DLS) suggested slight increase in micellar size of mixed micelles than its components suggesting curcumin loading in mixed micelles. Fourier transform infrared spectroscopy (FTIR) revealed that phenolic hydroxyl group interacts with lipids which contribute to its enhanced solubility. Furthermore, the differential scanning calorimetry (DSC) and X-ray diffraction (XRD) study indicated the conversion of crystalline curcumin into amorphous form. In the pellet formulation, Gelucire® 48/16 acted as a binder and eliminated the requirement of additional binder. Microcrystalline cellulose (MCC) forms wet mass and retards the release of curcumin from pellets. Increase in concentration of water-soluble diluent increased drug release. The optimized formulation released more than 90% drug and maintains supersaturation level of curcumin for 2 h. Thus, mixed micellar system was effective delivery system for curcumin while pellet formulation is an interesting formulation strategy consisting semi-solid lipids.


Assuntos
Curcumina/síntese química , Micelas , Polietilenoglicóis/síntese química , Ácidos Polimetacrílicos/síntese química , Vitamina E/síntese química , Disponibilidade Biológica , Curcumina/farmacocinética , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Excipientes/síntese química , Excipientes/farmacocinética , Polietilenoglicóis/farmacocinética , Ácidos Polimetacrílicos/farmacocinética , Solubilidade , Vitamina E/farmacocinética , Difração de Raios X/métodos
6.
Soft Matter ; 16(19): 4569-4573, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32373877
7.
J Mater Sci Mater Med ; 31(8): 61, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32696259

RESUMO

In this work, pH-sensitive hydrogel nanoparticles based on N-isopropyl acrylamide (NIPAM) and methacrylic acid (MAA) at various molar ratios, were synthesized and characterized in terms of physicochemical and biological properties. FTIR and 1HNMR spectra confirmed the successful synthesis of the copolymer that formed nanoparticles. AFM images and FE-SEM micrographs showed that nanoparticles were spherical, but their round-shape was slightly compromised with MAA content; besides, the size of particles tends to decrease as MAA content increased. The hydrogels nanoparticles also exhibited an interesting pH-sensitivity, displaying changes in its particle size when changes in pH media occurred. Biological characterization results indicate that all the synthesized particles are non-cytotoxic to endothelial cells and hemocompatible, although an increase of MAA content leads to a slight increase in the hemolysis percentage. Therefore, the pH-sensitivity hydrogels may serve as a versatile platform as self-regulated drug delivery systems in response to environmental pH changes.


Assuntos
Acrilamidas/síntese química , Hidrogéis/síntese química , Ácidos Polimetacrílicos/síntese química , Acrilamidas/química , Acrilamidas/farmacologia , Animais , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/fisiologia , Bovinos , Células Cultivadas , Liofilização , Hemólise/efeitos dos fármacos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Teste de Materiais , Metacrilatos/síntese química , Metacrilatos/química , Nanopartículas/química , Tamanho da Partícula , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia , Testes de Toxicidade
8.
Molecules ; 25(14)2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32698371

RESUMO

Glucosinolates (GLs) are of great interest for their potential as antioxidant and anticancer compounds. In this study, macroporous crosslinked copolymer adsorbents of poly (glycidyl methacrylate) (PGMA) and its amine (ethylenediamine, diethylamine, triethylamine)-modified derivatives were prepared and used to purify the GLS glucoerucin in a crude extract obtained from a cruciferous plant. These four adsorbents were evaluated by comparing their adsorption/desorption and decolorization performance for the purification of glucoerucin from crude plant extracts. According to the results, the strongly basic triethylamine modified PGMA (PGMA-III) adsorbent showed the best adsorption and desorption capacity of glucoerucin, and its adsorption data was a good fit to the Freundlich isotherm model and pseudo-second-order kinetics; the PGMA adsorbent gave the optimum decolorization performance. Furthermore, dynamic adsorption/desorption experiments were carried out to optimize the purification process. Two glass columns were serially connected and respectively wet-packed with PGMA and PGMA-III adsorbents so that glucoerucin could be decolorized and isolated from crude extracts in one process. Compared with KCl solution, aqueous ammonia was a preferable desorption solvent for the purification of glucoerucin and overcame the challenges of desalination efficiency, residual methanol and high operation costs. The results showed that after desorption with 10% aqueous ammonia, the purity of isolated glucoerucin was 74.39% with a recovery of 80.63%; after decolorization with PGMA adsorbent, the appearance of glucoerucin was improved and the purity increased by 11.30%. The process of using serially connected glass columns, wet-packed with PGMA and PGMA-III, may provide a simple, low-cost, and efficient method for the purification of GLs from cruciferous plants.


Assuntos
Aminas/química , Brassicaceae/química , Glucosinolatos/isolamento & purificação , Ácidos Polimetacrílicos/química , Adsorção , Glucose/análogos & derivados , Glucose/química , Glucose/isolamento & purificação , Glucosinolatos/química , Concentração de Íons de Hidrogênio , Imidoésteres/química , Imidoésteres/isolamento & purificação , Cinética , Ácidos Polimetacrílicos/síntese química , Soluções , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Am Chem Soc ; 141(7): 3100-3109, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30674187

RESUMO

Polymer brush coatings are frequently prepared by radical polymerization, a notoriously oxygen sensitive process. Glucose oxidase (GOx) can inexpensively enable radical polymerization in solution by enzymatically consuming oxygen as it oxidizes glucose. Here, we report the growth of polymeric brushes using GOx-assisted atom transfer radical polymerization (ATRP) from a surface while open to air. Specifically, we grew a set of biomedically relevant polymer brushes, including poly(oligo(ethylene glycol) methacrylate) (POEGMA), poly(2-dimethylaminoethyl methacrylate) (PDMAEMA), poly(sulfobetaine methacrylate) (PSBMA), and poly(2-(methylsulfinyl)ethyl acrylate (PMSEA). For each of these polymers, we monitored GOx-assisted and GOx-free ATRP reaction kinetics in real time using quartz crystal microbalance (QCM) and verified findings with localized surface plasmon resonance (LSPR). We modeled brush growth kinetics considering bimolecular termination. This model fit our data well ( r2 > 0.987 for all samples) and shows the addition of GOx increased effective kinetic chain lengths, propagation rates, and reproducibility. We tested the antifouling properties of the polymer brush coatings against human blood plasma and were surprised to find that coatings prepared with GOx repelled more plasma proteins in all cases than their GOx-free counterparts.


Assuntos
Glucose Oxidase/química , Ácidos Polimetacrílicos/síntese química , Incrustação Biológica/prevenção & controle , Glucose/química , Humanos , Oxigênio/química , Plasma/química , Polimerização , Técnicas de Microbalança de Cristal de Quartzo , Ressonância de Plasmônio de Superfície
10.
Small ; 15(42): e1903784, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31448570

RESUMO

Biodegradable polycaprolactone (PCL) has been widely applied as a scaffold material in tissue engineering. However, the PCL surface is hydrophobic and adsorbs nonspecific proteins. Some traditional antifouling modifications using hydrophilic moieties have been successful but inhibit cell adhesion, which is not ideal for tissue engineering. The PCL surface is modified with bioinspired zwitterionic poly[2-(methacryloyloxy)ethyl choline phosphate] (PMCP) via surface-initiated atom transfer radical polymerization to improve cell adhesion through the unique interaction between choline phosphate (CP, on PMCP) and phosphate choline (PC, on cell membranes). The hydrophilicity of the PCL surface is significantly enhanced after surface modification. The PCL-PMCP surface reduces nonspecific protein adsorption (e.g., up to 91.7% for bovine serum albumin) due to the zwitterionic property of PMCP. The adhesion and proliferation of bone marrow mesenchymal stem cells on the modified surface is remarkably improved, and osteogenic differentiation signs are detected, even without adding any osteogenesis-inducing supplements. Moreover, the PCL-PMCP films are more stable at the early stage of degradation. Therefore, the PMCP-functionalized PCL surface promotes cell adhesion and osteogenic differentiation, with an antifouling background, and exhibits great potential in tissue engineering.


Assuntos
Incrustação Biológica , Diferenciação Celular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Poliésteres/farmacologia , Ácidos Polimetacrílicos/farmacologia , Engenharia Tecidual , Adsorção , Animais , Animais Recém-Nascidos , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Fosforilcolina/síntese química , Fosforilcolina/farmacologia , Espectroscopia Fotoeletrônica , Poliésteres/síntese química , Ácidos Polimetacrílicos/síntese química , Ratos Sprague-Dawley , Propriedades de Superfície , Água/química
11.
Langmuir ; 35(5): 1242-1248, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29940737

RESUMO

A new class of mixed-charged zwitterionic copolymer poly(aminoethyl methacrylate)- co-poly(methacrylic acid)- co-poly( n-butyl methacrylate) (CPMA) was prepared as drug nanocarrier for efficient intracellular delivery of Doxorubicin (DOX). The mixed-charged CPMA copolymer could readily assemble to micelles in physiological environment (pH 7.4) with the size of 42.6 nm and zeta potential of -26 mV, which would lead to a prolonged circulation time and enhanced tumor penetration. However, the micelles formed large aggregates due to the protonation of carboxyl groups at extracellular tumor pH (pH 6.5). Meanwhile, the zeta potential of CPMA micelles increased from -26 mV to -6 mV when the solution pH was changed from pH 7.4 to pH 6.5. The increase of size and zeta potential at extracellular tumor pH could benefit the retention of micelles in tumor matrix and uptake by cancer cells. The DOX-loaded mixed-charged CPMA micelles could induce a higher internalization at pH 6.5 than 7.4 at varied time periods. Moreover, cytotoxicity assay demonstrated that the blank micelles showed excellent biocompatibility, but were highly cytotoxic toward KB cells after loading with DOX. Thus, the mixed-charged zwitterionic polymeric micelles might be a promising carrier for tumor acidic environment responsive drug delivery.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Micelas , Ácidos Polimetacrílicos/química , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/toxicidade
12.
Langmuir ; 35(5): 1895-1901, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30145900

RESUMO

Zwitterionic polymers are continually suggested as promising alternatives to tune the surface/interface properties of materials in many fields because of their unique molecular structures. Tremendous efforts have been devoted to immobilizing zwitterionic polymers (polyzwitterions, PZIs) on the material surfaces. However, these efforts usually suffer from cumbersome and time-consuming procedures. Herein we report a one-step strategy to facilely achieve the bioinspired polydopamine/polyzwitterion (PDA/PZI) coatings on various substrates. It requires only 30 min to form PDA/PZI coatings by mixing oxidant, dopamine, and zwitterionic monomers, including carboxybetaine methacrylate (CBMA), sulfobetaine methacrylate (SBMA), and 2-methacryloxyethyl phosphorylcholine (MPC). These bioinspired coatings display multifunctional properties such as underwater antioil-adhesion and antifreezing thanks to their high hydrophilicity and underwater superoleophobicity. The coatings even show the antiadhesion property for crude oil with high viscosity. Therefore, the PDA/PZI-coated meshes are efficient for separating both light oil and crude oil from oil/water mixtures. All these results demonstrate that the one-step strategy is a facile approach to design and exploit the bioinspired PDA/PZI coatings for diverse applications.


Assuntos
Betaína/química , Indóis/química , Metacrilatos/química , Petróleo , Fosforilcolina/análogos & derivados , Polímeros/química , Ácidos Polimetacrílicos/química , Betaína/síntese química , Congelamento , Indóis/síntese química , Metacrilatos/síntese química , Fosforilcolina/síntese química , Fosforilcolina/química , Polímeros/síntese química , Ácidos Polimetacrílicos/síntese química , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Propriedades de Superfície , Água/química
13.
Langmuir ; 35(5): 1391-1403, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30134095

RESUMO

A procedure for the preparation of copolymers bearing sulfobetaine and carboxybetaine methacrylic-based monomers by free-radical polymerization is described and discussed. A combination of monomers affects the upper critical solution temperature (UCST) in water and in the presence of a simple NaCl electrolyte while retaining the zwitterionic character. In addition, hydrogel samples were prepared and showed tunable water structure and mechanical properties. The total nonfreezable water content decreases with the amount of carboxybetaine segment in the hydrogel feed and the compression moduli were in a range of 0.7-1.6 MPa. Responses to external conditions such as temperature and ion strength were investigated and a potential application such as modulated thermal detection is proposed. The presence of the carboxylate group in the carboxybetaine segment enables a small fluorescence probe and peptide bearing RDG motif to be attached to polymer and hydrogel samples, respectively. The hydrogel samples functionalized with the RGD motif exhibit controlled cell adhesion. Such synthetic strategy based on combination of different zwitterionic segments offers a simple pathway for the development of zwitterionic materials with programmable properties.


Assuntos
Adesão Celular/efeitos dos fármacos , Ácidos Polimetacrílicos/farmacologia , Água/química , Células 3T3 , Animais , Betaína/análogos & derivados , Betaína/química , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Camundongos , Concentração Osmolar , Polimerização , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Temperatura de Transição , Substâncias Viscoelásticas/síntese química , Substâncias Viscoelásticas/química , Substâncias Viscoelásticas/farmacologia
14.
Langmuir ; 35(5): 1846-1857, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30134656

RESUMO

Fibrillogenesis of amyloid ß-protein (Aß) is a pathological hallmark of Alzheimer's disease, so inhibition of Aß aggregation is considered as an important strategy for the precaution and treatment of AD. Curcumin (Cur) has been recognized as an effective inhibitor of Aß fibrillogenesis, but its potential application is limited by its poor bioavailability. Herein, we proposed to conjugate Cur to a zwitterionic polymer, poly(carboxybetaine methacrylate) (pCB), and synthesized three Cur@pCB conjugates of different degrees of substitution (DS, 1.9-2.9). Cur@pCB conjugates self-assembled into nanogels of 120-190 nm. The inhibition effects of Cur@pCB conjugates on the fibrillation and cytotoxicity of Aß42 was investigated by extensive biophysical and biological analyses. Thioflavin T fluorescence assays and atomic force microscopic observations revealed that the Cur@pCB conjugates were much more efficient than molecular curcumin on inhibiting Aß42 fibrillation, and cytotoxicity assays also indicated the same tendency. Of the three conjugates, Cur1@pCB of the lowest DS (1.97) exhibited the best performance; 5 µM Cur1@pCB functioned similarly with 25 µM free curcumin. Moreover, 5 µM Cur1@pCB increased the cell viability by 43% but free curcumin at the same concentration showed little effect. It is considered that the highly hydrated state of the zwitterionic polymers resulted in the superiority of Cur@pCB over free curcumin. Namely, the dense hydration layer on the conjugates strongly stabilized the bound Aß on curcumin anchored on the polymer, suppressing the conformational transition of the protein to ß-sheet-rich structures. This was demonstrated by circular dichroism spectroscopy, in which Cur1@pCB was proven to be the strongest in the three conjugates. The research has thus revealed a new function of zwitterionic polymer pCBMA and provided new insights into the development of more potent nanoinhibitors for suppressing Aß fibrillogenesis and cytotoxicity.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Betaína/análogos & derivados , Betaína/química , Curcumina/análogos & derivados , Metacrilatos/farmacologia , Fragmentos de Peptídeos/metabolismo , Ácidos Polimetacrílicos/química , Multimerização Proteica/efeitos dos fármacos , Betaína/síntese química , Betaína/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/síntese química , Humanos , Metacrilatos/química , Ácidos Polimetacrílicos/síntese química
15.
Langmuir ; 35(5): 1100-1110, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29983076

RESUMO

The foreign body response (FBR) to implantable materials can negatively impact performance of medical devices such as the cochlear implant. Engineering surfaces that resist the FBR could lead to enhanced functionality including potentially improving outcomes for cochlear implant recipients through reduction in fibrosis. In this work, we coat poly(dimethylsiloxane) (PDMS) surfaces with two zwitterionic polymers, poly(sulfobetaine methacrylate) (pSBMA) and poly(carboxybetaine methacrylate) (pCBMA), using a simultaneous photografting/photo-cross-linking process to produce a robust grafted zwitterionic hydrogel. reduce nonspecific protein adsorption, the first step of the FBR. The coating process uses benzophenone, a photografting agent and type II photoinitiator, to covalently link the cross-linked zwitterionic thin film to the PDMS surface. As the concentration of benzophenone on the surface increases, the adhesive strength of the zwitterionic thin films to PDMS surfaces increases as determined by shear adhesion. Additionally, with increased concentration of the adsorbed benzophenone, failure of the system changes from adhesive delamination to cohesive failure within the hydrogel, demonstrating that durable adhesive bonds are formed from the photografting process. Interestingly, antifouling properties of the zwitterionic polymers are preserved with significantly lower levels of nonspecific protein adsorption on zwitterion hydrogel-coated samples compared to uncoated controls. Fibroblast adhesion is also dramatically reduced on coated substrates. These results show that cross-linked pSBMA and pCBMA hydrogels can be readily photografted to PDMS substrates and show promise in potentially changing the fibrotic response to implanted biomaterials.


Assuntos
Betaína/farmacologia , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/farmacologia , Dimetilpolisiloxanos/farmacologia , Metacrilatos/farmacologia , Ácidos Polimetacrílicos/farmacologia , Adsorção , Animais , Benzofenonas/química , Benzofenonas/efeitos da radiação , Betaína/síntese química , Adesão Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/síntese química , Dimetilpolisiloxanos/síntese química , Fibrinogênio/química , Fibroblastos/metabolismo , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Metacrilatos/síntese química , Polimerização/efeitos da radiação , Ácidos Polimetacrílicos/síntese química , Ratos
16.
Langmuir ; 35(5): 1935-1943, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30576152

RESUMO

Bacterial biofilms that are formed on surfaces are highly detrimental to many areas of industry and medicine. Seawater desalination by reverse osmosis (RO) suffers from biofilm growth on the membranes (biofouling), which limits its widespread use because biofouling decreases water permeance and necessitates module cleaning and replacement, leading to increased economic and environmental costs. Antimicrobial peptides (AMPs) bound covalently to RO membranes inhibit biofilm growth and might delay membrane biofouling. Here we examined how various hydrophilic membrane coatings composed of zwitterionic, neutral, positively charged, and poly(ethylene glycol) (PEG)-grafted polymers affected the biocidal activity and the biofilm inhibition of a covalently bonded AMP on RO membranes. AMP magainin-2 was linked by the copper-catalyzed azide-alkyne cycloaddition reaction to a series of RO membranes that were grafted with different methacrylate polymers. Surface characterization by infrared spectroscopy, X-ray photoelectron spectroscopy, and water drop contact angle gave evidence of successful RO modifications, and zeta potential analysis reflected the increase in surface charge due to the linked, positively charged peptide. All AMP-modified membranes inhibited Pseudomonas aeruginosa growth compared to unmodified membranes, and the grafted methacrylic polymers did not significantly interfere with the peptide activity. On the other hand, membranes coated with zwitterionic and other acrylate polymers including AMP attachment inhibited biofilm growth more than either the AMP or the polymer coating alone. This enhancement led to ∼20% less biofilm biovolume on the membrane surfaces. The combination of antimicrobial coatings with polymer coatings known to resist fouling might aid future designs of surface coatings susceptible to biofilm growth.


Assuntos
Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Magaininas/farmacologia , Membranas Artificiais , Ácidos Polimetacrílicos/química , Proteínas de Xenopus/farmacologia , Animais , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Química Click , Magaininas/química , Osmose , Ácidos Polimetacrílicos/síntese química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Propriedades de Superfície , Proteínas de Xenopus/química , Xenopus laevis
17.
Langmuir ; 35(5): 1450-1457, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30056704

RESUMO

Smart materials with both bactericidal and bacteria-resistant functions are promising for combating the infection concern of medical devices. Current work mostly utilizes hydrolysis to switch materials from antimicrobial to antifouling forms by incubating materials in aqueous solutions for hours to days. In this work, a new photoresponsive poly[2-((4,5-dimethoxy-2-nitrobenzyl)oxy)- N-(2-(methacryloyloxy)ethyl)- N, N-dimethyl-2-oxoethan-1-aminium] (polyCBNA) hydrogel was developed, incorporating the photolabile 4,5-dimethoxy-2-nitrobenzyl and cationic quaternary ammonium groups. The photolabile groups were readily cleaved from the hydrogel shortly upon UV irradiation at 365 nm (a long wavelength widely used for biomedical applications), leading to polymer surface charge switching from cationic to zwitterionic form. Protein adsorbed significantly on polyCBNA but easily desorbed from surfaces after UV irradiation. The cationic hydrogel as a precursor was shown to effectively kill the attached bacteria, and then quickly switched to zwitterionic antifouling form via photolysis, which released the attached bacteria from surfaces and prevented further bacterial attachment. Moreover, the adhered endothelial cells were easily detached from polyCBNA surfaces triggered by light, providing a facile and less destructive nonenzymatic approach to harvest cells. This smart photoresponsive polyCBNA polymer, with integrated antimicrobial and antifouling properties, holds great potential in biomedical applications such as self-sterilizing and self-cleaning coatings for implants, cell harvesting, and cell patterning.


Assuntos
Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Hidrogéis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Adsorção , Animais , Antibacterianos/síntese química , Antibacterianos/efeitos da radiação , Bovinos , Células Endoteliais/efeitos dos fármacos , Escherichia coli K12/efeitos dos fármacos , Fibrinogênio/química , Hidrogéis/síntese química , Hidrogéis/efeitos da radiação , Nitrobenzenos/síntese química , Nitrobenzenos/farmacologia , Nitrobenzenos/efeitos da radiação , Fotólise , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/efeitos da radiação , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/efeitos da radiação
18.
Langmuir ; 35(5): 1919-1926, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30204452

RESUMO

An adamantane-containing zwitterionic copolymer poly(2-(methacryloyloxy)ethyl phosphorylcholine)- co-poly(2-(methacryloyloxy)ethyl adamantane-1-carboxylate) (poly(MPC- co-MAda)) was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. The hydrophobic photosensitizer chlorin e6 (Ce6) was conjugated to ß-cyclodextrin (ß-CD) by glutathione (GSH)-sensitive disulfide bonds. The Ce6 conjugated supramolecular prodrug nanocarriers were fabricated due to the host-guest interaction between adamantane and ß-CD, which was confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The Ce6 conjugated prodrug nanocarriers showed reduction-responsive release of Ce6, which could result in the activation of Ce6. The generation of cytotoxic reactive oxygen species (ROS) was significantly enhanced due to the activation of Ce6. In additiona, the Ce6 conjugated prodrug nanocarriers could effectively inhibit the proliferation of cancer cells upon light irradiation.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Pró-Fármacos/farmacologia , Adamantano/análogos & derivados , Adamantano/síntese química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/efeitos da radiação , Clorofilídeos , Ciclodextrinas/síntese química , Ciclodextrinas/farmacologia , Ciclodextrinas/efeitos da radiação , Dissulfetos/síntese química , Dissulfetos/farmacologia , Dissulfetos/efeitos da radiação , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Humanos , Luz , Células MCF-7 , Fosforilcolina/análogos & derivados , Fosforilcolina/síntese química , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Porfirinas/síntese química , Porfirinas/efeitos da radiação , Pró-Fármacos/síntese química , Pró-Fármacos/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
19.
Langmuir ; 35(5): 1621-1630, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30558423

RESUMO

Mussel-inspired dopamine chemistry has increasingly been used for surface modification due to its simplicity, versatility, and strong reactivity for secondary functionalization with amine or thiol containing molecules. In this work, we demonstrate a facile surface modification technique using dopamine chemistry to prepare a zwitterionic polymer coating with both antifouling and antimicrobial property. Catechol containing adhesive monomer dopamine methacrylamide (DMA) was copolymerized with bioinspired zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) monomer, and the synthesized copolymers were covalently grafted onto the amino (-NH2) rich polyethylenimine (PEI)/polydopamine (PDA) codeposited surface to obtain a stable antifouling surface. The resulting surface was later used for in situ deposition of antimicrobial silver nanoparticles (AgNPs), facilitated by the presence of catechol groups of the coating. The modified surface was characterized using X-ray photoelectron spectroscopy (XPS), water contact angle measurements, and atomic force microscopy (AFM). This dual functional coating significantly reduced the adhesion of both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria and showed excellent resistance to bovine serum albumin (BSA) adsorption. This bioinspired and efficient surface modification strategy with dual functional coating promises its potential application in implantable biomedical devices.


Assuntos
Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Adsorção , Animais , Antibacterianos/síntese química , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Bovinos , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Dopamina/análogos & derivados , Escherichia coli/efeitos dos fármacos , Metacrilatos/química , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Polimerização , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Soroalbumina Bovina/química , Staphylococcus aureus/efeitos dos fármacos , Molhabilidade
20.
Biomacromolecules ; 20(1): 4-26, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30273485

RESUMO

The increasing price of barrels of oil, global warming, and other environmental problems favor the use of renewable resources to replace the petroleum-based polymers used in various applications. Recently, fatty acids (FAs) and their derivatives have appeared among the most promising candidates to afford novel and innovative bio-based (co)polymers because of their ready availability, their low toxicity, and their high versatility. However, the current literature mostly focused on FA-based polymers prepared by condensation polymerization or oxypolymerization, while only a few works have been devoted to radical polymerization due to the low reactivity of FAs through radical process. Thus, the aim of this Review is to give an overview of (i) the most common synthetic pathways reported in the literature to provide suitable monomers from FAs and their derivatives for radical polymerization, (ii) the available radical processes to afford FA-based (co)polymers, and (iii) the different applications in which FA-based (co)polymers have been used since the past few years.


Assuntos
Ácidos Graxos/química , Ácidos Polimetacrílicos/síntese química , Polimerização
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