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1.
Environ Sci Pollut Res Int ; 26(31): 31834-31845, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31489543

RESUMO

A novel multi-functional and environmental friendly tannic acid polymer (Fe3+-TA-HCHO) with Fe3+ and formaldehyde as double crosslinking agents together with cysteine as heteroatom source was prepared by a one-pot hydrothermal method. Characterization with transmission electron microscope (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FT-IR), and elemental analysis demonstrated that the Fe3+-TA-HCHO possessed uniform structure and particle size as well as plentiful functional groups. The resulted Fe3+-TA-HCHO material as a adsorbent to remove methylene blue, sunset yellow, Pb2+, Hg2+, and AsO33- from water. The results suggested that Fe3+-TA-HCHO polymer (pHpzc is 2.33) showed different adsorption properties for anionic pollutants (sunset yellow and AsO33-) and cationic pollutants (methylene blue, Pb2+, and Hg2+). The material exhibited remarkable selectivity for adsorption and separation of pollutants. The maximum adsorption capacities calculated from Langmuir model for methylene blue, Pb2+, and Hg2+ were 154.32, 819.67, and 699.30 mg g-1, respectively. This is the first time that tannic acid polymer is synthesized by double crosslinking method, which not only developed a promising adsorbent for selective removal of cation pollutants, but also opened up a new avenue for synthesis and application of tannic acid polymer.


Assuntos
Reagentes para Ligações Cruzadas/química , Formaldeído/química , Polímeros/síntese química , Taninos/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Ânions , Compostos Azo/química , Compostos Azo/isolamento & purificação , Cátions , Corantes/química , Corantes/isolamento & purificação , Reagentes para Ligações Cruzadas/síntese química , Ferro/química , Chumbo/química , Chumbo/isolamento & purificação , Mercúrio/química , Mercúrio/isolamento & purificação , Azul de Metileno/química , Azul de Metileno/isolamento & purificação , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
2.
Chem Pharm Bull (Tokyo) ; 67(8): 877-883, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366836

RESUMO

The 4-vinylpyrimidin-2-one nucleoside (T-vinyl) forms a cross-link with the RNA containing uracil at the complementary site at a high reaction rate. To obtain the stable T-vinyl derivative so that its reactivity is protected until it access to the target site, several derivatives were investigated, and the 2-thiopyridinyl- and 2-thiopyrimidinyl T-vinyl derivatives were determined to be good candidates. The 2-thiopyrimidinyl T-vinyl derivative was found to more efficiently cross-link with mRNA albeit having a better stability than the 2-thiopyridinyl T-vinyl derivative. The investigation using the luciferase (Luc) mRNA, the synthetic mRNA and non-cellular translation system revealed that the translation is terminated at the end of the cross-linked duplex between the mRNA and the oligoribonucleotide (ORN). Thus, the 2-thiopyrimidinyl T-vinyl derivative has successfully demonstrated both a good stability and high efficiency for the cross-linking reaction, and expanded its applicability in biological applications.


Assuntos
Reagentes para Ligações Cruzadas/química , Nucleosídeos/química , Oligorribonucleotídeos/química , RNA Mensageiro/química , Compostos de Vinila/química , Reagentes para Ligações Cruzadas/síntese química , Estrutura Molecular , Nucleosídeos/síntese química , Compostos de Vinila/síntese química
3.
J Colloid Interface Sci ; 553: 805-812, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31255942

RESUMO

HYPOTHESIS: Lactose (LAC) is a primary carbohydrate and energy source of milk has received intensive attention due to its' unique functional and nutritional properties. Many biological beneficences of LAC make it an appealing molecule to seek for designing functional interfaces. Therefore, crosslinked poly(lactose) (p(LAC)) microgel from lactose disaccharides for potential biomedical applications was pursued as biocolloids for the first time. EXPERIMENT: p(LAC) microgels prepared by chemical crosslinking with DiVinyl Sulfone (DVS) were chemically modified with ethylenediamine (EDA) to obtain amine-modified p(LAC) (p(LAC)-EDA) microgels to induce new functionalities and properties. Blood compatibilities of bare p(LAC)-EDA microgels were tested through hemolysis and blood clotting tests. Rosmarinic acid (RA) used as a model drug was loaded into p(LAC) and p(LAC)-EDA microgels to demonstrate their applicability to be used in drug loading and release applications. FINDINGS: A facile preparation of p(LAC) microgels with high yield, 90 ±â€¯5% and 0.5-50 µm size range was accomplished via water-in-oil (w/o) microemulsion crosslinking method. Upon chemical modification, the isoelectric point (IEP) from pH 1.8 for p(LAC) microgels changed to pH 7.7 for p(LAC)-EDA microgels, and the blood compatibility studies revealed that both microgels can be considered as blood compatible up to 2 mg/mL concentration, and only slight decrease in blood clotting index (BCI) of p(LAC)-EDA microgels was observed. Rosmarinic Acid (RA) was demonstrated to be released up to 4 days in phosphate buffer saline (PBS) with a linear release profile for p(LAC)-EDA microgels.


Assuntos
Reagentes para Ligações Cruzadas/química , Lactose/química , Polímeros/química , Pesquisa Biomédica , Reagentes para Ligações Cruzadas/síntese química , Lactose/síntese química , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície
4.
Biomater Sci ; 7(9): 3640-3651, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31165794

RESUMO

Tissue regeneration requires scaffolds that exhibit mechanical properties similar to the tissues to be replaced while allowing cell infiltration and extracellular matrix production. Ideally, the scaffolds' porous architecture and physico-chemical properties can be precisely defined to address regenerative needs. We thus developed techniques to produce hybrid fibers coaxially structured with a polycaprolactone core and a 4-arm, polyethylene glycol thiol-norbornene sheath. We assessed the respective effects of crosslink density and sheath polymer size on the scaffold architecture, physical and mechanical properties, as well as cell-scaffold interactions in vitro and in vivo. All scaffolds displayed high elasticity, swelling and strength, mimicking soft tissue properties. Importantly, the thiol-ene hydrogel sheath enabled tunable softness and peptide tethering for cellular activities. With increased photopolymerization, stiffening and reduced swelling of scaffolds were found due to intra- and inter-fiber crosslinking. More polymerized scaffolds also enhanced the cell-scaffold interaction in vitro and induced spontaneous, deep cell infiltration to produce collagen and elastin for tissue regeneration in vivo. The molecular weight of sheath polymer provides an additional mechanism to alter the physical properties and biological activities of scaffolds. Overall, these robust scaffolds with tunable elasticity and regenerative cues offered a versatile and effective platform for tissue regeneration.


Assuntos
Reagentes para Ligações Cruzadas/farmacologia , Microfibrilas/química , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Compostos de Sulfidrila/farmacologia , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Células Endoteliais/efeitos dos fármacos , Peso Molecular , Poliésteres/química , Polietilenoglicóis/química , Artéria Pulmonar/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Compostos de Sulfidrila/química
5.
Bioconjug Chem ; 30(6): 1636-1641, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31181891

RESUMO

Capsid of tomato bushy stunt virus consists of an outer coat protein shell decorated on an internal skeleton comprising a ß-annulus motif. We mimicked this capsid structure with our artificial viral capsid dressed up with protein. We synthesized the ß-annulus peptide bearing a Cys at the C-terminal side and linked it with Cys34 of the human serum albumin (HSA) via a bismaleimide linker. The ß-annulus peptide-HSA conjugate self-assembled into spherical structures of a 50-70 nm size range in the Tris-HCl buffer, with the ζ-potential of assemblies of such conjugate revealing that HSA proteins were displayed on the outer surface of the artificial viral capsid. Interestingly, the critical aggregation concentration (CAC) of the conjugate in the Tris-HCl buffer at 25 °C was approximately 0.01 µM, or 1/2500 lower than that of the unmodified ß-annulus peptides, suggesting that the artificial viral capsids were stabilized via HSA modification. The present strategy of constructing protein nanocapsule by self-assembly of a ß-annulus peptide-protein conjugate is simpler than that of previously reported protein nanocapsules.


Assuntos
Capsídeo/química , Cisteína/química , Nanocápsulas/química , Peptídeos/química , Albumina Sérica Humana/química , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Cisteína/síntese química , Humanos , Maleimidas/síntese química , Maleimidas/química , Modelos Moleculares , Peptídeos/síntese química , Albumina Sérica Humana/síntese química
6.
J Am Soc Mass Spectrom ; 30(9): 1643-1653, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31168746

RESUMO

Chemical cross-linking combined with mass spectrometry (CL-MS) is a powerful method for characterizing the architecture of protein assemblies and for mapping protein-protein interactions. Despite its proven utility, confident identification of cross-linked peptides remains a formidable challenge, especially when the peptides are derived from complex mixtures. MS cleavable cross-linkers are gaining importance for CL-MS as they permit reliable identification of cross-linked peptides by whole proteome database searching using MS/MS information. Here we introduce a novel class of MS cleavable cross-linkers called isotopomeric cross-linkers (ICLs), which allow for confident and efficient identification of cross-linked peptides by whole proteome database searching. ICLs are simple, symmetrical molecules that asymmetrically incorporate heavy and light stable isotopes into the two arms of the cross-linker. As a result of this property, ICLs automatically generate pairs of isotopomeric cross-linked peptides, which differ only by the positions of the heavy and light isotopes. Upon fragmentation during MS analysis, these isotopomeric cross-linked peptides generate unique isotopic doublet ions that correspond to the individual peptides in the cross-link. The doublet ion information is used to determine the masses of the two cross-linked peptides from the same MS2 spectrum that is also used for peptide spectrum matching (PSM) by sequence database searching. Here we present the rationale for and mechanism of cross-linked peptide identification by ICL-MS. We describe the synthesis of the ICL-1 reagent, the ICL-MS workflow, and the performance characteristics of ICL-MS for identifying cross-linked peptides derived from increasingly complex mixtures by whole proteome database searching.


Assuntos
Reagentes para Ligações Cruzadas/química , Espectrometria de Massas/métodos , Peptídeos/análise , Peptídeos/química , Reagentes para Ligações Cruzadas/síntese química , Isótopos/química , Proteoma/análise , Proteoma/química , RNA Polimerase II/análise , RNA Polimerase II/química , Soroalbumina Bovina/análise , Soroalbumina Bovina/química , Espectrometria de Massas por Ionização por Electrospray/métodos
7.
ACS Appl Mater Interfaces ; 11(26): 23584-23590, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31252498

RESUMO

The increased demand for water highlights the need to utilize reclaimed water of various types. In agriculture, for example, which is considered the largest consumer of freshwater, irrigation with treated wastewater can replace much of the need for freshwater. Wastewater is generally used for irrigation through drippers, releasing small amounts of water to the crops. The contaminants found in treated wastewater increase the accumulation of fouling on the drippers, ultimately culminating in blocking of water exit. Thus, there is a crucial need to develop novel approaches to limit biofilm formation on the dripper. Here, we describe the synthesis of N-halamine-derivatized cross-linked polymethacrylamide nanoparticles (NPs) by copolymerization of the monomer methacrylamide and the cross-linker monomer N, N-methylenebisacrylamide and their subsequent embedding in the polyethylene that is used to fabricate the drippers. The newly designed drip system was activated by chlorinating the incorporated NPs and then was fully characterized. The nanofunctionalized drippers were tested in the field, showing excellent antifouling activity for at least 5 months compared to the control. In addition, the inherent recharging capacity of the antifouling NPs constitutes yet another valuable advantage of the currently reported technology.


Assuntos
Irrigação Agrícola , Aminas/química , Nanopartículas/química , Águas Residuárias/química , Acrilamidas/síntese química , Acrilamidas/química , Aminas/síntese química , Produtos Agrícolas , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Água Doce/química , Humanos , Eliminação de Resíduos Líquidos
8.
Macromol Rapid Commun ; 40(15): e1900149, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31111990

RESUMO

The fabrication of block copolymer (BCP) vesicles with controlled membrane permeability and promising stability remains a considerable challenge. Herein, a new type of pH-responsive and self-crosslinked vesicle based on a hydrolytically hindered urea bond is reported. This kind of vesicle is formed by the self-assembly of a pH-responsive and hydrolytically self-crosslinkable copolymer poly(ethylene glycol)-block-poly[2-(3-(tert-butyl)-3-ethylureido)ethyl methacrylate-co-2-(diethylamino)ethyl methacrylate] (PEG-b-P(TBEU-co-DEA)). The BCP can be easily synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(3-(tert-butyl)-3-ethylureido)ethyl methacrylate (TBEU) and 2-(diethylamino)ethyl methacrylate (DEA) using PEG-based macro-chain transfer agent. The copolymer could self-assemble into stable vesicles by the hydrophobic interaction and in situ cross-linking between amines and isocyanates after the hydrolysis of the hindered urea bonds without any catalyst. Dynamic light scattering (DLS) studies show that the vesicles exhibit enhanced stability against the dilution of organic solvent, and the size can be adjusted through the change of pH values. Moreover, the alkaline phosphatase-loaded vesicles can act as nano-reactor and enable free diffusion of small molecules into the vesicles, followed by the significantly improved fluorescence intensity of phosphate-caged fluorescein. This self-crosslinking and pH-sensitive vesicles may serve as a smart platform in controlled drug delivery and molecular reactor.


Assuntos
Reagentes para Ligações Cruzadas/síntese química , Polímeros/síntese química , Reagentes para Ligações Cruzadas/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
9.
Colloids Surf B Biointerfaces ; 181: 94-101, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31125923

RESUMO

A cross-linkable gemcitabine (GEM)-containing reduction-sensitive polymeric micelles based on the copolymer poly(PEG-co-CMA-co-GEM) was successfully fabricated. The copolymer which synthesized by one-step radical copolymerization of poly(ethylene glycol) methacrylate (PEGMA), 7-(2-Methylacryloylethoxy)-4-methylcoumarin (CMA), and 2-((2-hydroxyethyl)disulfanyl)ethyl acrylate (HSEA-GEM), endowed the micelles with "stealth" surface in circulation, photo cross-linkable property, and reduction-sensitivity. The designed micelles were fabricated by self-assembly of the copolymer in aqueous solution followed by UV-light induced cross-linking of coumarin moieties to enhance stability, which would not disassemble even below critical micelle concentration (CMC) or in non-selective solvent (DMSO/H2O 1:1). In vitro drug release curve demonstrated that the intracellular-mimicking reductive microenvironment could accelerated the GEM release of the prodrug micelles. These micelles could be effectively internalized by BxPC-3 pancreatic cancer cells according to confocal laser scanning microscopy (CLSM) detection and flow cytometry analysis. Meanwhile, methyl thiazolyl tetrazolium (MTT) assay demonstrated that the cross-linked prodrug micelles could efficiently inhibit the proliferation of BxPC-3 cells.


Assuntos
Antineoplásicos/farmacologia , Reagentes para Ligações Cruzadas/farmacologia , Desoxicitidina/análogos & derivados , Sistemas de Liberação de Medicamentos , Metacrilatos/farmacologia , Polietilenoglicóis/farmacologia , Pró-Fármacos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Desoxicitidina/química , Desoxicitidina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Metacrilatos/química , Micelas , Estrutura Molecular , Oxirredução , Tamanho da Partícula , Polietilenoglicóis/química , Pró-Fármacos/química , Propriedades de Superfície , Células Tumorais Cultivadas
10.
Carbohydr Polym ; 216: 45-53, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047081

RESUMO

Herein the construction of a strong gelatin hydrogel is presented by using pullulan dialdehyde (PDA) as a macromolecular crosslinker. The resultant PDA crosslinked gelatin hydrogels (G-PDA) exhibit extremely high mechanical strength, manifested in the achieved optimal compressive stress of 5.80 MPa at 80% strain, which is up to 152 times higher than pure gelatin hydrogel. The G-PDA were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The extent of crosslinking was determined by ninhydrin assay. The results suggested that the synergistic effect of dual-crosslinking, which is composed of short- and long-range covalent crosslinking and thermoreversible physical crosslinking, may played a key role in enhancing the load-bearing capacity of ensuing hydrogels. The swelling and enzymatic degradation of G-PDA are gradually limited with increasing PDA concentration. The result from MTT assay demonstrated that G-PDA is non-cytotoxic against MC3T3 cells, regardless of the concentrations of PDA.


Assuntos
Aldeídos/química , Materiais Biocompatíveis/química , Reagentes para Ligações Cruzadas/química , Gelatina/química , Glucanos/química , Hidrogéis/química , Aldeídos/síntese química , Aldeídos/toxicidade , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Colagenases/química , Força Compressiva , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/toxicidade , Módulo de Elasticidade , Gelatina/síntese química , Gelatina/toxicidade , Glucanos/síntese química , Glucanos/toxicidade , Hidrogéis/síntese química , Hidrogéis/toxicidade , Hidrólise , Camundongos , Oxirredução , Ácido Periódico/química , Porosidade
11.
Carbohydr Polym ; 216: 63-71, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047083

RESUMO

The effect of hydrazide linkers on the formation and mechanical properties of hyaluronan hydrogels was intensively evaluated. The reaction kinetics of hydrazone formation was monitored by NMR spectroscopy under physiological conditions where polyaldehyde hyaluronan (unsaturated: ΔHA-CHO, saturated: HA-CHO) was reacted with various hydrazides to form hydrogels. Linear (adipic, oxalic dihydrazide) and branched (N,N´,N´´-tris(hexanoylhydrazide-6-yl)phosphoric triamide and 4-arm-PEG hydrazide) hydrazides were compared as crosslinking agents. The mechanical properties of hydrogels were also modified by attaching a hydrophobic chain to HA-CHO; however, it was found that this modification did not lead to an increase in hydrogel stiffness. Cytotoxicity tests showed that all tested hydrazide crosslinkers reduced the viability of cells only slightly, and that the final hyaluronan hydrogels were non-toxic materials.


Assuntos
Reagentes para Ligações Cruzadas/química , Ácido Hialurônico/análogos & derivados , Hidrazinas/química , Hidrazonas/química , Hidrogéis/química , Acilação , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/toxicidade , Módulo de Elasticidade , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Hidrazinas/síntese química , Hidrazinas/toxicidade , Hidrazonas/síntese química , Hidrazonas/toxicidade , Hidrogéis/síntese química , Hidrogéis/toxicidade , Concentração de Íons de Hidrogênio , Cinética , Camundongos , Células Swiss 3T3
12.
Carbohydr Polym ; 217: 160-167, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079673

RESUMO

Polysaccharides can be modified by reactive functional groups to enable chemical crosslinking. We studied how different methods of crosslinking methacrylate-functionalized chitosan affected the network structures and various properties relevant for utilization of the chemically crosslinked hydrogels in biomedical applications, including tissue engineering and delivery of therapeutic agents. Four chitosan hydrogels were made by either the free radical polymerization with varying initiation kinetics and an addition of chain transfer agents or the based-catalyzed Michael-type addition reaction. Four chitosan hydrogels having identical polymer fractions at equilibrium swelling exhibited marked differences in shear moduli, dextran diffusion rate, and especially enzymatic degradation behaviors. Hydrogels made by the free radical polymerization with no chain transfer agent were highly resistant to complete degradation by enzyme for an extended period. We inferred that such resistance originated from chain bundles characterized by densely branched networks of chitosan chains, which was determined by small-angle X-ray scattering analysis.


Assuntos
Quitosana/química , Hidrogéis/química , Quitosana/síntese química , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Dextranos/química , Difusão , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Humanos , Hidrogéis/síntese química , Hidrólise , Metacrilatos/síntese química , Metacrilatos/química , Muramidase/química , Polimerização
13.
Macromol Rapid Commun ; 40(12): e1900115, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31021501

RESUMO

Donor-acceptor crosslinked poly[poly(ethylene glycol) methyl ether-methacrylate]-block-poly[1,1'-bis(2-ethylpentyl)-6-methyl-6'-(5-methyl-3-vinylthiophen-2-yl)-[3,3'-biindoline]-2,2'-dione] (poly(PEGMA)m -b-poly(VTIID)n ) nanoparticles with various vinylthiophene donor/isoindigo acceptor ratios are synthesized successfully. The prepared nanoparticles have uniform sizes and well-defined core-shell nanostructures. The intramolecular charge transfer is effectively enhanced due to the incorporation of acceptor groups after the crosslinking reaction. A transistor memory device is assembled using the synthesized polymer and has nonvolatile flash-type memory and amphiphilic trapping behavior. The optimized devices exhibit a significant memory window of approximately 38 V, a retention ability of over 104 s, and an endurance of at least 100 cycles. This study examines multiple applications of crosslinked core-shell nanoparticles, which demonstrates their promise as charge-storage dielectric materials for use in organic memory devices.


Assuntos
Reagentes para Ligações Cruzadas/química , Nanopartículas/química , Polímeros/química , Transistores Eletrônicos , Reagentes para Ligações Cruzadas/síntese química , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície
14.
Chem Commun (Camb) ; 55(27): 3899-3902, 2019 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-30869692

RESUMO

A novel DNA nanotetrad mediated crosslinking catalytic hairpin assembly (CCHA) is reported to generate clumps of cross-linked mesh products for high-contrast and simultaneous imaging of multiple mRNAs in living cells.


Assuntos
Técnicas Biossensoriais , Sobrevivência Celular , Reagentes para Ligações Cruzadas/química , DNA/química , Nanoestruturas/química , Imagem Óptica , RNA Mensageiro/análise , Catálise , Linhagem Celular Tumoral , Reagentes para Ligações Cruzadas/síntese química , Humanos
15.
Carbohydr Polym ; 212: 403-411, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30832874

RESUMO

Developing biomaterials based on the natural biomacromolecule silk sericin from Bombyx mori cocoon is of great interest for biomedical application. Dialdehyde carboxymethyl cellulose (DCMC) is derived from periodate oxidation of carboxy- methyl cellulose. Here, we developed a novel strategy of cross-linking of sericin with DCMC via the Schiff's base reaction. Fourier transform infrared spectroscopy and scanning electron microscopy indicated the formation of Schiff's base via the blending of sericin and DCMC. The mechanical properties tests suggested the covalent cross-linking effectively enhanced the tensile strength of sericin. The swelling test and water contact angle indicated the DCMC/SS film had excellent hydrophilicity, swellability. Additionally, we demonstrated the DCMC/SS film had excellent blood compatibility, cytocompatibility and promoting cell proliferation activity by the hemolysis ratio analysis, cell adhesion, cells viability and proliferation assays. The prepared DCMC/SS film has shown great promise in biomedical applications such as wound dressing, artificial skin and tissue engineering.


Assuntos
Carboximetilcelulose Sódica/síntese química , Celulose/análogos & derivados , Reagentes para Ligações Cruzadas/síntese química , Sericinas/síntese química , Seda/síntese química , Animais , Bandagens , Bombyx , Carboximetilcelulose Sódica/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Celulose/síntese química , Celulose/farmacologia , Reagentes para Ligações Cruzadas/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacologia , Camundongos , Células NIH 3T3 , Sericinas/farmacologia , Seda/farmacologia , Engenharia Tecidual/tendências
16.
J Pharm Biomed Anal ; 162: 117-123, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30236819

RESUMO

A novel polymer monolith based on the dicationic crosslinker 3,3'-(hexane-1,6-diyl)bis(1-vinylimidazolium) bromide, the monomer 1-vinylimidazole and a ternary porogen mixture (1-propanol, decan-1-ol and water) was developed and optimized for capillary electrochromatography. This aim was accomplished by adjusting the composition of individual constituents in the polymerization mixture and monitored based on several relevant parameters (e.g. pore structure by scanning electron microscopy, generation of electroosmotic flow, or permeability of material). The ultimately selected composition yielded a monolithic phase which excellently resolved six methylxanthines (including caffeine, theobromine and theophylline) in 15 min. Key requirements concerning the utilized buffer were an acidic pH of 3 and the addition of 50% acetonitrile; additionally, a negative voltage (-25 kV) had to be applied during analyses. The proposed separation mechanism was mixed mode, i.e. the combination of electrostatic repulsion and hydrophobic interaction. Monolith fabrication as well as separation efficiency were found to be highly repeatable, the material was mechanically stable and useable for at least 150 injections. Thus the presented stationary phase is definitely a very promising option for CEC.


Assuntos
Eletrocromatografia Capilar/métodos , Reagentes para Ligações Cruzadas/síntese química , Imidazóis/síntese química , Polivinil/síntese química , Xantinas/análise , Estrutura Molecular , Polimerização , Pressão , Solventes/química , Fatores de Tempo
17.
Talanta ; 192: 197-203, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348378

RESUMO

The quantification of proteins and peptides becomes more important besides mere identification in modern life sciences. Therefore, we have developed a new reagent that adds to the known metall-coded affinity tagging strategy employed in molecular and elemental mass spectrometry containing a photocleavable linker. A synthesis route was developed that provides the new reagent in good yields. The stability of the synthesized reagents was assessed under different temperature and illumination conditions. Labeling reactions were carried out at peptide and protein level, while also the fragmentation behavior of labeled peptides was assessed. In additional experiments, the photocleavability of the new reagent was examined. Upon irradiation with ultraviolet light, the photoproducts were liberated and could be used for quantification of labeled peptides.


Assuntos
Reagentes para Ligações Cruzadas/química , Lactalbumina/análise , Metais Pesados/química , Peptídeos/análise , Raios Ultravioleta , Reagentes para Ligações Cruzadas/síntese química , Espectrometria de Massas , Processos Fotoquímicos
18.
Cell Chem Biol ; 26(1): 48-59.e7, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30415967

RESUMO

Detection of dynamic protein-protein interactions within complexes and networks remains a challenging task. Here, we show by the example of the proteolytic ClpXP complex the utility of combined chemical cross-linking and mass spectrometry (XL-MS) to map interactions within ClpP and ClpX as well as across the enigmatic ClpX hexamer-ClpP heptamer interface. A few hot-spot lysines located in signature loops in ClpX were shown to be in proximity to several structural regions of ClpP providing an initial draft of the ClpX-ClpP interaction. Application of XL-MS further confirmed that Listeria monocytogenes ClpX interacts with the heterooligomeric ClpP1/2 complex solely via the ClpP2 apical site. Moreover, cellular interaction networks of human and bacterial proteases were elucidated via in situ chemical cross-linking followed by an antibody-based pull-down against ClpP. A subsequent mass spectrometric analysis demonstrated an up to 3-fold higher coverage compared with co-immunoprecipitation without cross-linker revealing unprecedented insight into intracellular ClpXP networks.


Assuntos
Reagentes para Ligações Cruzadas/química , Endopeptidase Clp/química , Endopeptidase Clp/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Reagentes para Ligações Cruzadas/síntese química , Feminino , Células Hep G2 , Humanos , Células K562 , Masculino , Espectrometria de Massas , Proteólise
19.
Macromol Rapid Commun ; 40(6): e1800819, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30549353

RESUMO

In this study, a simple yet versatile method is introduced to prepare a hyperbranched supramolecular polymer hydrogel by utilizing Type II photoinitiated self-condensing vinyl polymerization of N-acryloyl glycinamide, which can serve not only as an inimer providing branching sites, but also as a hydrogen-bonding cross-linker. The hyperbranched poly(N-acryloyl glycinamide) (HB-PNAGA) hydrogels demonstrate excellent mechanical performances with a tensile strength of 0.793-2.724 MPa, elongation at break of 203-902%, Young's modulus of 0.450-1.172 MPa, and maximal fracture energy of 2200 J m-2 , which are all superior to those of linear PNAGA hydrogels. The results indicate that the HB-PNAGA hydrogel is very stiff and tough due to much higher H-bonding cross-linking density formed in hyperbranched architecture. The high stiffness, toughness, and ease of preparation make these hyperbranched supramolecular hydrogels very attractive for application as soft supporting tissue replacements.


Assuntos
Reagentes para Ligações Cruzadas/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polímeros/química , Reagentes para Ligações Cruzadas/síntese química , Glicina/análogos & derivados , Glicina/química , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Ligação de Hidrogênio , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Estrutura Molecular , Polimerização , Polímeros/síntese química , Engenharia Tecidual
20.
J Colloid Interface Sci ; 538: 530-540, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544070

RESUMO

Herein, we report the successful synthesis of a series of poly (N-isopropylacrylamide) (PNIPA)/layered double hydroxides (LDHs)/nano-hydroxyapatite (nano-HA) hydrogels via in-situ radical polymerization. The internal morphology, thermo sensitivity, rheological properties, swelling behavior and hemocompatibility of the PNIPA/LDHs/HA composite hydrogels were systematically investigated. Results show that the hydrogels had a reversible sol-gel transformation around 33 °C. Interactions between the positively charged LDHs and negatively charged nano-HA particles created a highly porous hydrogel network. The composite hydrogels exhibited excellent hemocompatibility, incredible mechanical toughness and reversible swelling/deswelling behavior. To our knowledge, this is the first reported study to use two types of inorganic nanoparticle with opposing charges as hydrogel crosslinking agents. Based on its properties, we expect this hydrogel has broad applications potential in tissue engineering, drug delivery and biosensor development.


Assuntos
Reagentes para Ligações Cruzadas/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas/química , Temperatura , Reagentes para Ligações Cruzadas/síntese química , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
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