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1.
Anal Chim Acta ; 1093: 160-167, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735210

RESUMO

In this study, poly(butyl methacrylate-co-ethyleneglycol dimethacrylate) polymeric monoliths were in situ developed within 0.75 mm i.d. poly(ethylene-co-tetrafluoroethylene) (ETFE) tubing by UV polymerization via three different free-radical initiators (α,α'-azobisisobutyronitrile (AIBN), 2,2-dimethoxy-2-phenylacetophenone (DMPA) and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMPP). The influence of the nature of each photo-initiator and irradiation time on the morphological features of the polymer was investigated by scanning electron microscopy, and the chromatographic properties of the resulting microbore columns were evaluated using alkyl benzenes as test substances. The beds photo-initiated with MTMPP gave the best performance (minimum plate heights of 38 µm for alkyl benzenes) and exhibited a satisfactory reproducibility in the chromatographic parameters (RSD < 11%). These monolithic columns were also successfully applied to the separation of phenylurea herbicides, proteins and a tryptic digest of ß-casein.


Assuntos
Acetofenonas/química , Cromatografia Líquida de Alta Pressão/instrumentação , Morfolinas/química , Nitrilos/química , Ácidos Polimetacrílicos/química , Politetrafluoretileno/análogos & derivados , Propiofenonas/química , Acetofenonas/efeitos da radiação , Caseínas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/isolamento & purificação , Metacrilatos/química , Morfolinas/efeitos da radiação , Nitrilos/efeitos da radiação , Fragmentos de Peptídeos/isolamento & purificação , Compostos de Fenilureia/isolamento & purificação , Polimerização , Ácidos Polimetacrílicos/síntese química , Politetrafluoretileno/química , Propiofenonas/efeitos da radiação , Raios Ultravioleta
2.
Anal Chim Acta ; 1089: 78-89, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31627821

RESUMO

Novel molecularly imprinted polymer (MIP) for metformin was synthesized on the surface of magnetic multi-walled carbon nanotubes (MMWCNTs) as the support. Metformin was used as the template, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2'-azoisobutyronitrile (AIBN) as the initiator. The synthesized composite was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FTIR). The surface molecularly imprinted composite was used for magnetic solid phase microextraction (MSPME) of metformin before its chemiluminescence (CL) determination and its capability was compared with non-imprinted polymer (NIP). The central composite design was used for optimization as well as consideration of possible interaction of effective variables on extraction. Under the optimized conditions, the developed method exhibited the linear dynamic range of 0.5-50.0 µg L-1 with a detection limit of 0.13 µg L-1 and enhancement factor of 195.3 for the preconcentration of 100 mL of the sample and 500 µL of an eluent. The intra- and inter-day relative standard deviations (RSD%) at 5.0 µg L-1 level of metformin (n = 6) were 3.7 and 4.9%, respectively. The maximum adsorption capacity of the sorbent was found to be 80.0 mg g-1, the adsorption of metformin was endothermic and spontaneous and followed the Langmuir isotherm model. The adsorption kinetic was also found to be best fitted with the pseudo-second-order model. The designed method was successfully applied to the extraction and determination of metformin in biological fluids and water samples.


Assuntos
Metformina/análise , Nanotubos de Carbono/química , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Água Potável/análise , Cinética , Limite de Detecção , Metformina/sangue , Metformina/urina , Impressão Molecular , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Água do Mar/análise , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/urina
3.
Analyst ; 144(14): 4320-4330, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31192335

RESUMO

Restricted access molecularly imprinted polymers (RAMIPs) are hybrid materials that present selective binding sites for a template (or similar molecules), and an external hydrophilic layer that avoids the binding of proteins to the material, making them appropriate for the sample preparation of protein fluids. RAMIPs have been used successfully in online and offline solid phase extractions, but there is no application as a fiber in solid phase microextraction (SPME), to the best of our knowledge. In this paper, molecularly imprinted fibers were synthesized inside glass capillary tubes (0.53 mm i.d.), using diazepam and methacrylic acid as template and functional monomer, respectively. The MIP fibers were coated with a cross-linked bovine serum albumin (BSA) layer, resulting in RAMIP fibers that were used in the SPME of benzodiazepines directly from biological fluids. The BSA layer acts as a protective barrier that avoids the binding of proteins from the sample by an electrostatic repulsion mechanism. The protein exclusion capacity of the RAMIP fiber was about 98%, which is selective to benzodiazepines in comparison with other drugs (citalopram and fluoxetine). The SPME was optimized and the extraction conditions were set as follows: 1000 µL of the sample diluted with water (1 : 0.5, v : v), no pH adjustment, an extraction time of 20 min at 500 rpm, and elution with 200 µL of acetonitrile for 5 min at 500 rpm. The fibers were used in the SPME of benzodiazepines directly from plasma samples, followed by HPLC-DAD analyses. The method was linear for bromazepam (50-750 µg L-1), clonazepam (15-250 µg L-1), alprazolam (15-350 µg L-1), nordiazepam (100-2100 µg L-1) and diazepam (100-2600 µg L-1), with correlation coefficients higher than 0.97. Relative standard deviations (precision) and relative errors (accuracy) ranged from 0.5 to 20.0%, and -15.6 to 21.6%, respectively.


Assuntos
Benzodiazepinas/sangue , Ácidos Polimetacrílicos/química , Adsorção , Animais , Benzodiazepinas/química , Bovinos , Diazepam/química , Humanos , Cinética , Metacrilatos/química , Impressão Molecular/métodos , Ácidos Polimetacrílicos/síntese química , Estudo de Prova de Conceito , Soroalbumina Bovina/química , Microextração em Fase Sólida/instrumentação , Microextração em Fase Sólida/métodos
4.
Nat Chem ; 11(6): 578-586, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30988414

RESUMO

Polymerization reactions conducted inside cells must be compatible with the complex intracellular environment, which contains numerous molecules and functional groups that could potentially prevent or quench polymerization reactions. Here we report a strategy for directly synthesizing unnatural polymers in cells through free radical photopolymerization using a number of biocompatible acrylic and methacrylic monomers. This offers a platform to manipulate, track and control cellular behaviour by the in cellulo generation of macromolecules that have the ability to alter cellular motility, label cells by the generation of fluorescent polymers for long-term tracking studies, as well as generate a variety of nanostructures within cells. It is remarkable that free radical polymerization chemistry can take place within such complex cellular environments. This demonstration opens up a multitude of new possibilities for how chemists can modulate cellular function and behaviour and for understanding cellular behaviour in response to the generation of free radicals.


Assuntos
Radicais Livres/química , Polimerização/efeitos da radiação , Ácidos Polimetacrílicos/síntese química , Poliestirenos/síntese química , Acrilatos/química , Acrilatos/efeitos da radiação , Acrilatos/toxicidade , Citoesqueleto de Actina/efeitos dos fármacos , Compostos de Anilina/química , Compostos de Anilina/efeitos da radiação , Compostos de Anilina/toxicidade , Movimento Celular/efeitos dos fármacos , Fluorescência , Células HeLa , Humanos , Metacrilatos/química , Metacrilatos/efeitos da radiação , Metacrilatos/toxicidade , Propano/análogos & derivados , Propano/química , Propano/efeitos da radiação , Fase S/efeitos dos fármacos , Estirenos/química , Estirenos/efeitos da radiação , Estirenos/toxicidade , Raios Ultravioleta , Compostos de Vinila/química , Compostos de Vinila/efeitos da radiação , Compostos de Vinila/toxicidade
5.
Carbohydr Polym ; 207: 628-639, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600048

RESUMO

Here, we report synthesis of a terpolymeric covalently crosslinked hydrogel of hyaluronate (HA) as biomaterial with elasticity, mechanical properties and cell interactions via conventional free radical polymerization technique. To provide elasticity and mechanical properties, 2-hydroxyethyl acrylate (HEA) was grafted in HA, while to tune cellular interactions, gelatin methacryloyl (GM) was used as crosslinker. The composition and probable structure of the terpolymer (HA-g-pHEA-x-GM) were analysed by FTIR, 1H HR-MAS-NMR, and TGA analyses. The SEM and texture analyses of hydrogel showed interconnected micro-porous network and high mechanical properties, respectively. In vitro biocompatibility was studied against human chondrocytes, whereas, in vivo biocompatibility and tissue regeneration were confirmed using mouse model. The hydrogel releases model protein-bovine serum albumin, and corticosteroid drug-dexamethasone in a sustain way at pH 7.4 and 37 °C. Overall, the tunable mechanical properties, micro-porous network, and cytocompatibility of the HA-g-pHEA-x-GM hydrogel highlights its potential applicability in cartilage tissue engineering and drug delivery.


Assuntos
Materiais Biocompatíveis/química , Gelatina/química , Ácido Hialurônico/química , Hidrogéis/química , Ácidos Polimetacrílicos/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Bovinos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Dexametasona/química , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Elasticidade , Gelatina/síntese química , Gelatina/toxicidade , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Hidrogéis/síntese química , Hidrogéis/toxicidade , Masculino , Camundongos Endogâmicos C57BL , Polimerização , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/toxicidade , Porosidade , Soroalbumina Bovina/química
6.
Carbohydr Polym ; 205: 167-175, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30446092

RESUMO

Serum stability is a crucial factor for ideal polymeric gene vectors. In this work, a series of serum-tolerant and low-toxicity glycopolymers/poly(ethyleneimine) (PEI) complexes were designed for gene delivery. Atomic transfer radical polymerization (ATRP) was used to synthesize the comb-shaped random copolymers dextran-g-poly(2-dimethylaminoethyl methacrylate-co-2-lactobionamidoethyl methacrylate) (DDrL). Then DDrLs/PEI were investigated for their use as plasmid DNA (pDNA) vectors, which can completely condense the pDNA into nanoparticles. The DDrLs/PEI/pDNA complexes in serum-containing media showed better stability than PEI/pDNA complexes. in vitro gene transfection studies showed that DDrLs/PEI exhibited a remarkable transfection efficiency enhancement in the presence of serum compared to that in serum-free conditions. Moreover, the transfection level of DDrLs/PEI were two orders of magnitude higher than that of PEI alone in the presence of 30% serum. DDrLs/PEI complexes with galactose enhanced pDNA delivery to hepatocytes, with higher protein expression in ASGPr-presenting HepG2 than in HeLa cells, which lack the receptor. All of the DDrLs/PEI/pDNA complexes had lower cytotoxicity than PEI/pDNA.


Assuntos
DNA/genética , Dextranos/química , Hepatócitos/metabolismo , Polietilenoimina/química , Ácidos Polimetacrílicos/química , Transfecção , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dextranos/síntese química , Dextranos/toxicidade , Humanos , Tamanho da Partícula , Plasmídeos , Polietilenoimina/síntese química , Polietilenoimina/toxicidade , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/toxicidade
7.
Carbohydr Polym ; 205: 203-210, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30446096

RESUMO

Medical cotton gauzes were modified by grafting poly(methacrylic acid) (PMAA) via free radical polymerization to obtain wound dressings with antimicrobial and drug delivery properties. The effect of several reaction parameters including monomer and initiator concentrations, reaction time, and temperature was studied. The grafting was confirmed by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), swelling studies, and scanning electron microscopy (SEM). The grafted cotton gauzes (gauze-g-PMAA) samples were loaded with ZnO nanoparticles to endow with antibacterial properties. Also, they were tested as drug eluting systems using nalidixic acid as antimicrobial agent. The antibacterial activity of the ZnO-loaded gauze-g-PMAA samples was evaluated against Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis). The PMAA-grafted gauzes showed antibacterial activity and inhibited the growth of both microorganisms. These results suggest that the PMAA-grafted cotton gauzes could be used in the biomedical area particularly as antimicrobial and drug-eluting wound dressings.


Assuntos
Antibacterianos/química , Bandagens , Celulose/química , Fibra de Algodão , Sistemas de Liberação de Medicamentos , Ácidos Polimetacrílicos/química , Celulose/síntese química , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Ácido Nalidíxico/química , Ácido Nalidíxico/farmacologia , Nanopartículas/química , Polimerização , Ácidos Polimetacrílicos/síntese química , Staphylococcus epidermidis/efeitos dos fármacos , Óxido de Zinco/química , Óxido de Zinco/farmacologia
8.
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
9.
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
10.
Macromol Rapid Commun ; 40(2): e1800140, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29687509

RESUMO

A versatile method for synthesis of block copolymer nanoassemblies via initiators for continuous activator regeneration (ICAR) atom transfer radical polymerization (ATRP) dispersion polymerization in a low molecular weight poly(ethylene glycol) (PEG) is discussed. This ICAR ATRP dispersion polymerization uses a low concentration of CuBr2 catalyst, which is stable under atmospheric conditions and is soluble in most polar solvents and employs a polymerization medium of viscous and nonvolatile PEG. Through this ICAR ATRP dispersion polymerization, various block copolymer nanoassemblies, including poly(ethylene glycol)-block-polystyrene, poly(ethylene glycol)-block-poly(methyl methacrylate), and poly(2-hydroxypropyl methacrylate)-block-poly(methyl methacrylate), have been synthesized. The parameters affecting the size and morphology of the block copolymer nanoassemblies are briefly discussed.


Assuntos
Cobre/química , Nanoestruturas/química , Polietilenoglicóis/química , Polimerização , Polímeros/química , Catálise , Técnicas de Química Sintética/métodos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Estrutura Molecular , Peso Molecular , Nanoestruturas/ultraestrutura , Polietilenoglicóis/síntese química , Polímeros/síntese química , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Poliestirenos/síntese química , Poliestirenos/química , Solventes/química
11.
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
12.
Macromol Rapid Commun ; 40(2): e1800331, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29974536

RESUMO

The evolution of particle morphology occurring during polymerization-induced self-assembly (PISA) of a block copolymer poly(oligo(ethylene glycol) methacrylate)-b-poly(benzyl methacrylate) (POEGMA-b-PBzMA) is studied. A well-controlled reversible addition-fragmentation chain transfer (RAFT) polymerization yields nano-objects with various morphologies: spheres, aggregates, worm-like structures, and vesicles. A comparison of the morphology of the nano-objects formed from two different chain-length stabilizers established that the unreacted monomer played an important role during the morphology transitions, which is contrary to previous observations. In addition, morphology evolution to higher-order structures could be attained simply by extending the reaction time, after reaching full monomer conversion.


Assuntos
Técnicas de Química Sintética/métodos , Nanopartículas/química , Polimerização , Ácidos Polimetacrílicos/química , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Ácidos Polimetacrílicos/síntese química
13.
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
14.
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
15.
Macromol Rapid Commun ; 40(2): e1800327, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30027663

RESUMO

A series of hydrophilic poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA) macroinitiators and stabilizers are synthesized in methanol through in situ photo-controlled bromine-iodine transformation living radical polymerization, where ethyl α-bromophenylacetate (EBPA) is the initial initiator and is converted to an iodo-type initiator in the presence of NaI. The subsequent photo-controlled polymerization-induced self-assembly (photo-PISA) process is achieved by adding a second monomer, hydrophobic benzyl methacrylate (BnMA), under irradiation with blue light emitting diode (LED) light at room temperature. The effect of the target degree of polymerization (DP) of PPEGMA, PBnMA, as well as the solids content on the self-assembly behavior of block copolymer PPEGMA-b-PBnMA is evaluated by gel permeation chromatography (GPC), nuclear magnetic resonance (NMR) spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS) characterization. Resulting uniform spherical micelles and vesicle aggregates are observed.


Assuntos
Bromo/química , Técnicas de Química Sintética/métodos , Iodo/química , Luz , Polimerização/efeitos da radiação , Ácidos Polimetacrílicos/química , Cromatografia em Gel , Difusão Dinâmica da Luz , Interações Hidrofóbicas e Hidrofílicas , Metacrilatos/química , Metanol/química , Microscopia Eletrônica de Transmissão , Modelos Químicos , Estrutura Molecular , Ácidos Polimetacrílicos/síntese química
16.
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
17.
Anal Chem ; 90(22): 13409-13418, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30346153

RESUMO

In this work, isothermal titration calorimetry (ITC) is employed as an affinity agent screening method for the surface-enhanced Raman scattering (SERS) detection of aflatoxin B1 (AFB1). AFB1, a potent carcinogen produced by a fungus that infects crops, is an important target due to the monitoring required based on its FDA regulation. Polymer affinity agents, like those studied here, have the potential to enable separation and detection of relevant small molecules such as pesticides, drugs, and biological toxins, like AFB1, especially when paired with a vibrational spectroscopy technique such as SERS. Herein, seven homopolymers were synthesized to be evaluated as AFB1 affinity agents based on hypothetical hydrogen bonding interactions. Nitrogen-inclusive poly( N-(2-aminoethyl) methacrylamide) (pAEMA) polymers and their oxygen analogs, poly(2-hydroxyethyl methacrylate) (pHEMA) were evaluated. ITC was demonstrated as an effective method for rapid screening among the polymer affinity agents. Chain lengths between seven and 39 repeat units were synthesized to study length-based variance in affinity agent performance. An ITC method was optimized and used for the rapid screening of polymer affinity agents. The results were compared to those generated by SERS. Good agreement between the ITC results and follow-up SERS sensing experiments showcased ITC's screening potential for analytical applications such as separation and detection.


Assuntos
Aflatoxina B1/análise , Carcinógenos/análise , Ácidos Polimetacrílicos/química , Calorimetria/métodos , Teoria da Densidade Funcional , Ligação de Hidrogênio , Modelos Químicos , Estrutura Molecular , Ácidos Polimetacrílicos/síntese química , Análise Espectral Raman/métodos
18.
Langmuir ; 34(45): 13705-13712, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30351955

RESUMO

Molecular nanoparticles have been used as building blocks in the synthesis of functional materials. The grand challenges in the synthesis of the functional materials are precise control of the structures and functionalities of the materials by using nanoparticles with different architectures and properties. Monotethered single-chain polymeric nanoparticles (SCPN) are a type of nanosized asymmetric particles formed by intramolecular cross-linking of linear diblock copolymer chains. Monotethered SCPNs can be used as elemental building blocks for the fabrication of well-defined advanced structures. In this research, synthesis of biohybrid materials based on coassembly of bovine serum albumin (BSA) molecules and monotethered SCPNs is investigated. Due to the asymmetric structure of the SCPNs, positively charged SCPNs and negatively charged protein molecules coassemble into biohybrid vesicles with SCPNs on the layers and protein molecules in the walls. The self-assembled structures were analyzed by using dynamic light scattering, transmission electron microscopy, cryo-transmission electron microscopy, and atomic force microscopy. The average size of the biohybrid vesicles can be controlled by the molar ratio of SCPNs to BSA. The protein molecules in the biohybrid vesicles maintain most of the activities. This research paves a new way for the synthesis of functional biohybrid structures, and the materials can be used as protein carriers.


Assuntos
Nanoconjugados/química , Nanopartículas/química , Ácidos Polimetacrílicos/química , Soroalbumina Bovina/química , Animais , Bovinos , Metacrilatos/química , Tamanho da Partícula , Polietilenoglicóis/química , Ácidos Polimetacrílicos/síntese química
19.
ACS Nano ; 12(10): 10272-10280, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30272942

RESUMO

The utility of layer-by-layer (LbL) coated microneedle (MN) skin patches for transdermal drug delivery has proven to be a promising approach, with advantages over hypodermal injection due to painless and easy self-administration. However, the long epidermal application time required for drug implantation by existing LbL MN strategies (15-90 min) can lead to potential medication noncompliance. Here, we developed a MN platform to shorten the application time in MN therapies based on a synthetic pH-induced charge-invertible polymer poly(2-(diisopropylamino) ethyl methacrylate- b-methacrylic acid) (PDM), requiring only 1 min skin insertion time to implant LbL films in vivo. Following MN-mediated delivery of 0.5 µg model antigen chicken ovalbumin (OVA) in the skin of mice, this system achieved sustained release over 3 days and led to an elevated immune response as demonstrated by significantly higher humoral immunity compared with OVA administration via conventional routes (subcutaneously and intramuscularly). Moreover, in an ex vivo experiment on human skin, we achieved efficient immune activation through MN-delivered LbL films, demonstrated by a rapid uptake of vaccine adjuvants by the antigen presenting cells. These features, rapid administration and the ability to elicit a robust immune response, can potentially enable a broad application of microneedle-based vaccination technologies.


Assuntos
Adjuvantes Imunológicos/farmacologia , Agulhas , Oligodesoxirribonucleotídeos/farmacologia , Ácidos Polimetacrílicos/síntese química , Receptor de Morte Celular Programada 1/imunologia , Pele/efeitos dos fármacos , Adjuvantes Imunológicos/administração & dosagem , Administração Cutânea , Animais , Galinhas , Sistemas de Liberação de Medicamentos , Feminino , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/administração & dosagem , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Ácidos Polimetacrílicos/química , Pele/imunologia , Vacinação
20.
Langmuir ; 34(37): 11101-11109, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30148645

RESUMO

In this paper, a series of amphiphilic diblock polymers of poly(hydroxyethylacrylamide)- b-poly(1H,1H-pentafluoropropyl methacrylate) (PHEAA- b-PFMA) were grafted from silicon wafer via surface-initiated atom transfer radical polymerization (SI-ATRP). Surface wettability and chemical compositions of the modified surfaces were characterized by contact angle goniometer and X-ray photoelectron spectroscopy (XPS) respectively. Molecular weight and polydispersity of each block were measured using gel permeation chromatography (GPC). The topography and the microphase separation behavior of PHEAA- b-PFMA surfaces were investigated by atomic force microscope (AFM). The results show that only when the grafting density (σ) and thickness of PHEAA brush were in the range of 0.9-1.3 (chain/nm2) and 6.6-15.1 nm, respectively, and the ratio of PFMA/PHEAA varied from 89/42 to 89/94, could the diblock copolymer phase separate into nanostructures. Further, the antiprotein adsorption performance of the modified surfaces against BSA, fibrinogen, and lysozyme was studied. The results indicated the modified surfaces could reduce the protein adsorption compared to the pristine silicon wafer. For Fibrinogen, the antiadsorption effect of PHEAA- b-PFMA-modified surfaces with microphase segregation was better than that of corresponding PHEAA modified surfaces. The results provide further evidence that surface composition and microphase segregation of fluorinated moieties of block copolymer brushes significantly impact protein adsorption behaviors.


Assuntos
Resinas Acrílicas/química , Fibrinogênio/química , Muramidase/química , Ácidos Polimetacrílicos/química , Soroalbumina Bovina/química , Resinas Acrílicas/síntese química , Adsorção , Animais , Bovinos , Ácidos Polimetacrílicos/síntese química , Silício/química , Propriedades de Superfície , Molhabilidade
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