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1.
J Chromatogr A ; 1635: 461755, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33278673

RESUMO

In this work, a biocompatible monolithic column based micro-solid-phase extraction (µ-SPE) method was developed for biological fluid analysis. A novel nanoparticle-based polyacrylonitrile monolithic column (C30 NP-PMC) was fabricated by incorporating triacontyl (C30) modified silica nanoparticles (NPs) into the polyacrylonitrile monolithic matrix through thermally induced phase separation. With efficient mass transfer and sorption capacity, C30 NP-PMC exhibited outstanding performance for the extraction of carotenoids and fat-soluble vitamins (FSVs) from human serum samples, superior to commercial C18 cartridges as well as liquid-liquid extraction (LLE) method. Under optimal conditions, the proposed µ-SPE method coupled with high-performance liquid chromatography-diode array detection (HPLC-DAD) achieved satisfactory limits of detection (LODs) (1.5-75.0 ng/mL) and good recoveries (85.0-106.5 %) with relative standard deviations (RSDs) of less than 12.1% by consuming lower sorbent (35.0 mg) and organic solvent (0.8 mL). Successful application of the developed method demonstrated the great potential of such monolithic sorbents for efficient isolation and preconcentration of trace analytes from blood samples.


Assuntos
Resinas Acrílicas/química , Análise Química do Sangue/métodos , Carotenoides/isolamento & purificação , Nanopartículas/química , Extração em Fase Sólida/instrumentação , Microextração em Fase Sólida , Vitaminas/isolamento & purificação , Análise Química do Sangue/instrumentação , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Dióxido de Silício , Solventes , Vitaminas/sangue
2.
Chem Biol Interact ; 333: 109310, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33212047

RESUMO

We wish to present a simple, rapid, cost-effective and environmentally safe method for staining proteins in polyacrylamide gels, using aqueous-based natural extracts from fresh green walnut (Juglans regia) hulls/husks. The technique takes not more than 10 min for staining and is comparable in sensitivity to the most commonly used Coomassie R-250 staining method when applied to different concentrations of Bovine Serum Albumin (BSA) and various amounts of E. coli extracts. The protein (BSA) band (~0.5 µg) and E. coli extract comprising ~25 µg total protein can be visualized on polyacrylamide gels. Compared to both Coomassie and Ponceau S staining, the current method displayed more intense bands when proteins are transferred to polyvinylidene fluoride (PVDF) membrane. Although the walnut-dye (WD) method does not require a time-consuming destaining step, excess background stain can simply be removed by washing in water. Extract from old dried black husks and extract from fresh green husks kept for a year was also effective. Using LC-MS, Myricetin and/or Kaempferol were found to be active compounds responsible for staining proteins. Compared to traditional Coomassie method, the inclusion of expensive and toxic solvents (methanol and acetic acid) is completely avoided resulting in positive health, environmental and economic benefits. In view of all these advantages, the WD method has immense potential to replace currently used protein staining techniques.


Assuntos
Química Verde/economia , Química Verde/métodos , Juglans/química , Extratos Vegetais/química , Proteínas/química , Coloração e Rotulagem/economia , Coloração e Rotulagem/métodos , Resinas Acrílicas/química , Géis
3.
Food Chem ; 338: 128144, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33092004

RESUMO

A weak ion-exchange membrane (P-COOH) was synthesized by alkaline hydrolysis of a polyacrylonitrile nanofiber membrane prepared by electrospinning process. The P-COOH membrane was characterized for its physical properties and its application for purification of lysozyme from chicken egg white was investigated. The lysozyme adsorption efficiency of the P-COOH membrane operating in a stirred cell contactor (Millipore, Model 8010) was evaluated. The effects of key parameters such as the feed concentration, the rotating speed, the flow rate of feed and the operating pressure were studied. The results showed successful purification of lysozyme with a high recovery yield of 98% and a purification factor of 63 in a single step. The purification strategy was scaled-up to the higher feedstock loading volume of 32.7 and 70 mL using stirred cell contactors of Model 8050 and 8200, respectively. The scale-up processes achieved similar purification results, proving linear scalability of the purification technique adopted.


Assuntos
Fracionamento Químico/instrumentação , Clara de Ovo , Membranas Artificiais , Muramidase/isolamento & purificação , Nanofibras/química , Resinas Acrílicas/química , Adsorção , Animais , Troca Iônica , Muramidase/química
4.
Food Chem ; 337: 127763, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791431

RESUMO

In this work, water-resistant poly (vinyl alcohol) (PVA)/poly (acrylic acid) (PAA) electrospun fibers encapsulating tangeretin (Tan) were fabricated by emulsion-electrospinning. To optimize the electrospinning condition, the size and morphology of electrospun fibers were characterized by dynamic light scattering (DLS), optical light microscope, fluorescence microscopy, and scanning electron microscopy (SEM), respectively. The optimized initial concentration of PVA/PAA was 10% (w/w) with a mass ratio of 3:7. The time and temperature of optimized thermal crosslinking treatment were 2 h and 145 °C, respectively. The results of XRD and SEM showed that the Tan was successfully incorporated into smooth PVA/PAA electrospun fibers and those fibers possessed nano-diameter size and high porosity. The encapsulation of Tan had no significant impact on the antioxidant activity of PVA/PAA/Tan crosslinking electrospun fibers. The in vitro release test showed the PVA/PAA/Tan crosslinking electrospun fibers achieved durable release profiles and lower burst release rates than that from the pure Tan emulsion. Based on these results, it is concluded that PVA/PAA/Tan crosslinking electrospun fibers prepared by emulsion-electrospinning serve as a promising technique in the fields of water-insoluble drug delivery and slow-release.


Assuntos
Resinas Acrílicas/química , Antioxidantes/química , Portadores de Fármacos/química , Eletricidade , Flavonas/química , Álcool de Polivinil/química , Liberação Controlada de Fármacos , Emulsões
5.
Food Chem ; 335: 127631, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32736157

RESUMO

In this work, sodium 4-styrenesulfonate functionalized polyacrylonitrile nanofibers mat (SS/PAN NFM) was firstly prepared and applied as 96-well plate solid-phase extraction adsorbent for quantitative determination of seven ß-agonists residues in pork samples. The functional modification endowed the SS/PAN NFM with superior adsorption performance for target ß-agonists. The adsorption process is spontaneous (ΔG < 0), the initial adsorption rate can reach 6.03-9.09 mg/g/min and the maximum adsorption capacity is calculated to be 48.3 mg/g at 298 K. Moreover, SS/PAN NFM can be reused for 12 times without degradation in adsorption capability. Combined with UPLC-MS/MS, the limits of detection can reach 0.006-0.24 µg/kg, the recoveries ranged from 87.2% to 111% and the relative standard deviations of intra-day and inter-day precisions were in the scope of 1.75%-11.6% and 5.08%-13.5%, respectively. The obtained results fully demonstrated the practicability of this method in preventing the hazard of ß-agonists residues.


Assuntos
Agonistas Adrenérgicos beta/análise , Agonistas Adrenérgicos beta/isolamento & purificação , Análise de Alimentos/métodos , Nanofibras/química , Poliestirenos/química , Carne Vermelha/análise , Extração em Fase Sólida/métodos , Resinas Acrílicas/química , Agonistas Adrenérgicos beta/química , Adsorção , Animais , Contaminação de Alimentos/análise , Limite de Detecção , Suínos
6.
Chemosphere ; 262: 128072, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182132

RESUMO

A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine functionality present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.


Assuntos
Alumínio/química , Caprilatos/análise , Fluorcarbonetos/análise , Dietilamida do Ácido Lisérgico/análogos & derivados , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Resinas Acrílicas/química , Adsorção , Carvão Vegetal/química , Dietilamida do Ácido Lisérgico/química , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
7.
Chemosphere ; 262: 127836, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805657

RESUMO

Polyacrylonitrile fiber was successfully modified with triazine-based dendrimer via grafting method as a promising adsorbent for removal of mercury species from aqueous media. The prepared adsorbent was characterized by elemental analysis, scanning electron microscope, Fourier transform infrared spectroscopy, porous structure analysis and X-ray photoelectron spectroscopy, providing the evidence of successful fabrication. The adsorption conditions were found via varying pH, dosage, coexisting substances, contact time, temperature and concentration. Adsorption performance, described better by the pseudo-second-order kinetics with intraparticle diffusion as rate controlling step and Langmuir isotherm model, indicated a chemisorption process with the maximum Langmuir adsorption amount of 227.64 mg g-1 for mercury ions. Thermodynamically, adsorption of mercury ions was spontaneous and endothermic. Desorption and regeneration experiments demonstrated that it could be reused in five successive adsorption cycles without significant loss of its original performance. Experimental data and density functional theory calculation disclosed the coordination geometries and chelating mechanism between the adsorbent and mercury ions. The proposed study would provide a new prospect for the purification of mercury in aqueous system by functionalizing commercial polyacrylonitrile fiber with dendrimers.


Assuntos
Resinas Acrílicas/química , Dendrímeros/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Difusão , Concentração de Íons de Hidrogênio , Íons/análise , Cinética , Mercúrio/análise , Temperatura , Termodinâmica , Águas Residuárias/química , Água/química , Poluentes Químicos da Água/análise
8.
Int J Nanomedicine ; 15: 9611-9625, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33293810

RESUMO

Purpose: This study evaluated tensile bond strength (TBS) between anterior acrylic teeth and denture bases made of high-impact heat-cured acrylic resin (HI PMMA) impregnated with zirconia nanoparticles. Materials and Methods: A total of 30 specimens (each specimen containing a set of six upper anterior teeth) were fabricated from HI PMMA denture base acrylic resin reinforced with different weight concentrations of zirconia nanoparticles: 0% (control), 1.5%, 3%, 5%, 7% and 10%. TBS was tested according to a British standard (BS EN ISO 22112: 2017). A one-way analysis of variance (ANOVA) was employed with a Tukey post-hoc test. Results: TBS values between the anterior teeth (central and lateral incisors and canine) and HI-PMMA denture base groups containing 7 wt.% (261.5 ± 66.0 N, 172.5 ± 57.4 N and 271.9 ± 86.3 N) and 10 wt.% (332.1 ± 122.9 N, 165.4 ± 48.7 N and 301.6 ± 73.2 N) zirconia were significantly lower compared to the control group (645.4 ± 84.8 N, 306.1 ± 81.6 N and 496.7 ± 179.1 N) and the other nanocomposite groups. However, TBS values for HI PMMA with 1.5 wt.% (534.4 ± 115.3 N, 304.7 ± 86.4 N, 514.0 ± 143.2 N), 3 wt.% (685.7 ± 159.6 N, 281.1 ± 78.3 N, 462.6 ± 122.1 N) and 5 wt.% (514.5 ± 134.3 N, 229.8 ± 67.3 N, 387.2 ± 99.4 N) zirconia showed slightly lower values than that of the control group but these were not significant. Failure modes between the teeth and denture base nanocomposites were predominantly cohesive fractures, which were clinically acceptable according to the Standard. Conclusion: The addition of zirconia nanoparticles to HI PMMA denture base at high concentration (7 wt.% and 10 wt. %) significantly (p<0.05) reduced the bonding strength for all types of anterior teeth compared to the control group.


Assuntos
Bases de Dentadura , Zircônio/química , Resinas Acrílicas/química , Colagem Dentária , Análise do Estresse Dentário , Teste de Materiais , Nanopartículas Metálicas , Polimetil Metacrilato/química , Resistência à Tração
9.
Int J Nanomedicine ; 15: 7263-7278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061380

RESUMO

Purpose: Efficient intracellular delivery of a therapeutic compound is an important feature of smart drug delivery systems (SDDS). Modification of a carrier structure with a cell-penetrating ligand, ie, cholesterol moiety, is a strategy to improve cellular uptake. Cholesterol end-capped poly(N-isopropylacrylamide)s offer a promising foundation for the design of efficient thermoresponsive drug delivery systems. Methods: A series of cholesterol end-capped poly(N-isopropylacrylamide)s (PNIPAAm) with number-average molar masses ranging from 3200 to 11000 g·mol-1 were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization from original xanthate-functionalized cholesterol and self-assembled into micelles. The physicochemical characteristics and cytotoxicity of cholesterol end-capped poly(N-isopropylacrylamide)s have been thoroughly investigated. Results: Phase transition temperature dependence on the molecular weight and hydrophilic/hydrophobic ratio in the polymers were observed in water. Biological test results showed that the obtained materials, both in disordered and micellar form, are non-hemolytic, highly compatible with fibroblasts, and toxic to glioblastoma cells. It was found that the polymer termini dictates the mode of action of the system. Conclusion: The cholesteryl moiety acts as a cell-penetrating agent, which enables disruption of the plasma membrane and in effect leads to the restriction of the tumor growth. Cholesterol end-capped PNIPAAm showing in vitro anticancer efficacy can be developed not only as drug carriers but also as components of combined/synergistic therapy.


Assuntos
Resinas Acrílicas/química , Antineoplásicos/farmacologia , Colesterol/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Adulto , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Portadores de Fármacos/efeitos adversos , Fibroblastos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Hemólise/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Micelas , Peso Molecular , Transição de Fase , Polimerização , Polímeros/química , Temperatura , Água
10.
AAPS PharmSciTech ; 21(7): 253, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32888086

RESUMO

We developed a pH-triggered in situ gel (ISG) for ocular delivery of vinpocetine to achieve systemic absorption and a brain-targeting effect in rats. Carbopol acted as a gelling agent combined with hydroxypropyl methylcellulose (HPMC) as a viscosity-enhancing agent. The concentration of Carbopol (0.2%, w/v) and HPMC (1.5%, w/v) was optimized for the ISG system. The optimized formulation was evaluated for studies on release in vitro, rheology, differential scanning calorimetry, ocular irritation, residence time, and in vivo pharmacokinetics. The vinpocetine ISG stayed longer in rabbit eyes than vinpocetine ointment. In vivo pharmacokinetics showed that compared with vinpocetine ointment, vinpocetine ISG attained a peak plasma concentration and area under the curve that was 1-2 folds greater in rat plasma. The Drug Targeting Index (DTI) was 1.06 and 1.26 for vinpocetine ointment and vinpocetine ISG, respectively, after ocular administration, showing that vinpocetine ISG had better distribution in rat brain. These results revealed that a pH-triggered ISG system via ocular administration could be an alternative approach compared with traditional ophthalmic formulations.


Assuntos
Sistemas de Liberação de Medicamentos , Géis/química , Concentração de Íons de Hidrogênio , Vasodilatadores/administração & dosagem , Alcaloides de Vinca/administração & dosagem , Resinas Acrílicas/química , Administração Oftálmica , Animais , Derivados da Hipromelose/química , Masculino , Coelhos , Ratos , Viscosidade
11.
Sci Rep ; 10(1): 15313, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943759

RESUMO

Accurate identification of both abundant and rare proteins hinges on the development of single-protein sensing methods. Given the immense variation in protein expression levels in a cell, separation of proteins by weight would improve protein classification strategies. Upstream separation facilitates sample binning into smaller groups while also preventing sensor overflow, as may be caused by highly abundant proteins in cell lysates or clinical samples. Here, we scale a bulk analysis method for protein separation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), to the single-molecule level using single-photon sensitive widefield imaging. Single-molecule sensing of the electrokinetically moving proteins is achieved by in situ polymerization of the PAGE in a low-profile fluidic channel having a depth of only ~ 0.6 µm. The polyacrylamide gel restricts the Brownian kinetics of the proteins, while the low-profile channel ensures that they remain in focus during imaging, allowing video-rate monitoring of single-protein migration. Calibration of the device involves separating a set of Atto647N-covalently labeled recombinant proteins in the size range of 14-70 kDa, yielding an exponential dependence of the proteins' molecular weights on the measured mobilities, as expected. Subsequently, we demonstrate the ability of our fluidic device to separate and image thousands of proteins directly extracted from a human cancer cell line. Using single-particle image analysis methods, we created detailed profiles of the separation kinetics of lysine and cysteine -labeled proteins. Downstream coupling of the device to single-protein identification sensors may provide superior protein classification and improve our ability to analyze complex biological and medical protein samples.


Assuntos
Análise Serial de Proteínas/métodos , Proteínas/química , Resinas Acrílicas/química , Calibragem , Linhagem Celular Tumoral , Cisteína/química , Eletroforese em Gel de Poliacrilamida/métodos , Humanos , Lisina/química , Peso Molecular , Neoplasias/patologia , Proteômica , Dodecilsulfato de Sódio/química
12.
Sci Rep ; 10(1): 15520, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968120

RESUMO

Technological advances have made it possible to examine dental resin composites using 3D nanometer resolution. This investigation aims to characterize existing dental nano-hybrid and micro-hybrid resin composites through comparing and contrasting nano-computed tomography (nano-CT) with micro-CT and high-resolution SEM images. Eight commercially available and widely used dental resin composites, 2 micro-hybrid and 6 nano-hybrid were researched. Cured samples were examined and characterized using nano-CT (resolution 450 nm) and compared with micro-CT images (resolution 2 µm). Acquired images were reconstructed and image analysis was carried out to determine porosity and pore morphology. A comprehensive comparison of scanning micrograph images unsurprisingly revealed that the nano-CT images displayed greater detail of the ultrastructure of cured dental resin composites. Filler particle diameters and its volumes were lower when measured using nano-CT, porosity being higher where analysed at higher resolution. There were large variations between the examined materials. Fewer voids were found in Tetric EvoCeram and IPS Empress Direct, the smallest pores being found in Universal XTE and Tetric EvoCeram. Nano-CT was successfully used to investigate the morphology of dental resin composites and showed that micro-CT gives a lower porosity and pore size but overestimates filler particle size. There were large discrepancies between the tested composites. Evidence of porosities and pores within a specimen is a critical finding and it might have a detrimental effect on a material's clinical performance.


Assuntos
Resinas Acrílicas/química , Resinas Compostas/química , Poliuretanos/química , Resinas Sintéticas/química , Microtomografia por Raio-X/métodos , Microscopia Eletrônica de Varredura , Nanotecnologia/métodos
13.
Nat Protoc ; 15(9): 3030-3063, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32807909

RESUMO

Materials that sense and respond to biological signals in their environment have a broad range of potential applications in drug delivery, medical devices and diagnostics. Nucleic acids are important biological cues that encode information about organismal identity and clinically relevant phenotypes such as drug resistance. We recently developed a strategy to design nucleic acid-responsive materials using the CRISPR-associated nuclease Cas12a as a user-programmable sensor and material actuator. This approach improves on the sensitivity of current DNA-responsive materials while enabling their rapid repurposing toward new sequence targets. Here, we provide a comprehensive resource for the design, synthesis and actuation of CRISPR-responsive hydrogels. First, we provide guidelines for the synthesis of Cas12a guide RNAs (gRNAs) for in vitro applications. We then outline methods for the synthesis of both polyethylene glycol-DNA (PEG-DNA) and polyacrylamide-DNA (PA-DNA) hydrogels, as well as their controlled degradation using Cas12a for the release of cargos, including small molecules, enzymes, nanoparticles and living cells within hours. Finally, we detail the design and assembly of microfluidic paper-based devices that use Cas12a-sensitive hydrogels to convert DNA inputs into a variety of visual and electronic readouts for use in diagnostics. Following the initial validation of the gRNA and Cas12a components (1 d), the synthesis and testing of either PEG-DNA or PA-DNA hydrogels require 3-4 d of laboratory time. Optional extensions, including the release of primary human cells or the design of the paper-based diagnostic, require an additional 2-3 d each.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Técnicas e Procedimentos Diagnósticos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Materiais Inteligentes/química , Resinas Acrílicas/química , Proteínas de Bactérias/metabolismo , Sequência de Bases , Proteínas Associadas a CRISPR/metabolismo , DNA/química , DNA/genética , Endodesoxirribonucleases/metabolismo , Humanos , Células K562 , Polietilenoglicóis/química , RNA Guia/genética
14.
Int J Nanomedicine ; 15: 5517-5526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801703

RESUMO

Introduction: Hypertension is a major health problem worldwide and is typically treated using oral drugs. However, the frequency of oral administration may result in poor patient compliance, and reduced bioavailability owing to the first-pass effect can also prove problematic. Methods: In this study, we developed a new transdermal-drug-delivery system (TDDS) for the treatment of hypertension using atenolol (ATE) based on poly(acrylic acid) (PAA)-decorated three-dimensional (3D) flower-like MoS2 nanoparticles (PAA-MoS2 NPs) that respond to NIR laser irradiation. The PAA-modified MoS2 NPs were synthesized and characterized using attenuated total reflection Fourier-transform infrared spectroscopy, X-ray diffraction measurements, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, and the sedimentation equilibrium method. The drug-loading efficiency and photothermal conversion effect were also explored. Results: The results showed that the colloidally stable PAA-MoS2 NPs exhibited a high drug-loading capacity of 54.99% and high photothermal conversion ability. Further, the capacity of the PAA-MoS2 NPs for controlled release was explored using in vitro drug-release and skin-penetration studies. The drug-release percentage was 44.72 ± 1.04%, and skin penetration was enhanced by a factor of 1.85 in the laser-stimulated group. Sustained and controlled release by the developed TDDS were observed with laser stimulation. Moreover, in vivo erythema index analysis verified that the PAA-MoS2 NPs did not cause skin irritation. Discussion: Our findings demonstrate that PAA-MoS2 NPs can be used as a new carrier for transdermal drug delivery for the first time.


Assuntos
Anti-Hipertensivos/administração & dosagem , Atenolol/administração & dosagem , Dissulfetos/química , Sistemas de Liberação de Medicamentos/métodos , Molibdênio/química , Nanopartículas/administração & dosagem , Resinas Acrílicas/química , Administração Cutânea , Animais , Anti-Hipertensivos/farmacocinética , Atenolol/efeitos adversos , Atenolol/farmacocinética , Sistemas de Liberação de Medicamentos/efeitos adversos , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Eritema/induzido quimicamente , Humanos , Lasers , Masculino , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Coelhos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Int J Nanomedicine ; 15: 4959-4967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764929

RESUMO

Background: Particle-based drug delivery systems (DDSs) have a demonstrated value for drug discovery and development. However, some problems remain to be solved, such as limited stimuli, visual-monitoring. Aim: To develop an intelligent multicolor DDSs with both near-infrared (NIR) controlled release and macroscopic color changes. Materials and Methods: Microparticles comprising GO/pNIPAM/PEGDA composite hydrogel inverse opal scaffolds, with dextran and calcium alginate hydrogel were synthesized using SCCBs as the template. The morphology of microparticle was observed under scanning electron microscopy, and FITC-dextran-derived green fluorescence images were determined using a confocal laser scanning microscope. During the drug release, FITC-dextran-derived green fluorescence images were captured using fluorescent inverted microscope. The relationship between the power of NIR and the drug release rate was obtained using the change in optical density (OD) values. Finally, the amount of drug released could be estimated quantitatively used the structural color or the reflection peak position. Results: A fixed concentration 8% (v/v) of PEGDA and 4mg/mL of GO was chosen as the optimal concentration based on the balance between appropriate volume shrinkage and structure color. The FITC-dextran was uniformly encapsulated in the particles by using 0.2 wt% sodium alginate. The microcarriers shrank because of the photothermal response and the intrinsic fluorescence intensity of FITC-dextran in the microparticles gradually decreased at the same time, indicating drug release. With an increasing duration of NIR irradiation, the microparticles gradually shrank, the reflection peak shifted toward blue and the structural color changed from red to orange, yellow, green, cyan, and blue successively. The drug release quantity can be predicted by the structural color of microparticles. Conclusion: The multicolor microparticles have great potential in drug delivery systems because of its vivid reporting color, excellent photothermal effect, and the good stimuli responsivity.


Assuntos
Portadores de Fármacos/química , Microesferas , Resinas Acrílicas/química , Alginatos/química , Cor , Dextranos/química , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Hidrogéis/química , Fenômenos Ópticos , Polietilenoglicóis/química
16.
Nat Commun ; 11(1): 4032, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788575

RESUMO

Hydrogel-based devices are widely used as flexible electronics, biosensors, soft robots, and intelligent human-machine interfaces. In these applications, high stretchability, low hysteresis, and anti-fatigue fracture are essential but can be rarely met in the same hydrogels simultaneously. Here, we demonstrate a hydrogel design using tandem-repeat proteins as the cross-linkers and random coiled polymers as the percolating network. Such a design allows the polyprotein cross-linkers only to experience considerable forces at the fracture zone and unfold to prevent crack propagation. Thus, we are able to decouple the hysteresis-toughness correlation and create hydrogels of high stretchability (~1100%), low hysteresis (< 5%), and high fracture toughness (~900 J m-2). Moreover, the hydrogels show a high fatigue threshold of ~126 J m-2 and can undergo 5000 load-unload cycles up to 500% strain without noticeable mechanical changes. Our study provides a general route to decouple network elasticity and local mechanical response in synthetic hydrogels.


Assuntos
Reagentes para Ligações Cruzadas/química , Hidrogéis/química , Poliproteínas/química , Estresse Mecânico , Resinas Acrílicas/química , Fluorescência , Fenômenos Mecânicos
17.
Macromol Rapid Commun ; 41(15): e2000249, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32608545

RESUMO

A thermo-responsive conjugated polymer, PFBT-gPA is synthesized by grafting the poly(N-isopropylacrylamide) (PNIPAAm) to the side chains of a conjugated polyfluorene derivative through atom transfer radical polymerization (ATRP). PFBT-gPA undergoes a reversible phase transition in water below and above the lower critical solution temperature (LCST) and the process is studied by differential scanning calorimetry (DSC) analysis and UV/vis absorption spectra. PFBT-gPA shows a good photostability under UV light irradiation especially above the LCST. Moreover, the photosensitizing performance of PFBT-gPA could be tuned simply by changing temperature. The unique properties of PFBT-gPA promise its potential applications in sensing and photodynamic therapy.


Assuntos
Resinas Acrílicas/química , Fluorenos/química , Polímeros/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Transição de Fase , Fotodegradação , Fármacos Fotossensibilizantes/química , Polimerização , Polímeros/síntese química , Polímeros/efeitos da radiação , Espectrometria de Fluorescência , Temperatura , Água/química
18.
J Chromatogr A ; 1625: 461298, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709341

RESUMO

This study has examined the batch binding behaviour of different thermo-responsive co-polymer grafted chromatographic materials under different temperature and protein loading conditions. The effect of molecular composition of poly(N-isopropylacrylamide) (PNIPAAm)-based co-polymers on the phase transition properties has been documented. Sixteen co-polymers of different compositions were synthesized by free radical polymerization methods. Most underwent relatively sharp phase transitions upon application of increasing temperature. However, the value of the lower critical solution temperature (LCST) varied due to differences in co-polymer compositions. In general, it was found that the LCST increased for co-polymers containing more hydrophilic moieties, but decreased for co-polymers with more hydrophobic moieties. Moreover, the LCST increased, together with increased width of the transition temperature, when highly branched monomeric moieties (i.e. N­tert­octyl groups) were present. When bulky side chains (octadecyl or triphenylmethyl groups) were located in the polymer structures the LCST transition was absent. Based on these findings, 6 thermo-responsive co-polymers of different compositions were individually immobilised onto cross-linked Sepharose 6 Fast Flow by a "grafting-from" method. Bovine holo-lactoferrin and bovine holo-transferrin at different concentrations in the range 1-100 mg/mL were then employed as target proteins to evaluate the adsorption behaviour under batch binding conditions with these different polymer grafted Sepharose 6 Fast Flow sorbents at two different temperatures. In general, all sorbents exhibited greater affinity and adsorption capacity for bovine holo-lactoferrin at 50 °C compared to 20 °C. In addition, the affinity and adsorption capacity of bovine holo-lactoferrin with positively charged copolymer grafted Sepharose 6 Fast Flow chromatographic sorbents at 20 °C and 50 °C were much lower than that found for negatively charged copolymer grafted Sepharose 6 Fast Flow sorbents, whilst the opposite trend was found with bovine holo-transferrin due to differences in the surface charge properties of these two proteins, indicative of different separation selectivity. Furthermore, the structure of the side chains present in the grafted copolymer structure was found to affect the adsorption performance of both proteins at 20 °C and 50 °C.


Assuntos
Polímeros/química , Proteínas/química , Reologia , Sefarose/química , Temperatura , Resinas Acrílicas/síntese química , Resinas Acrílicas/química , Adsorção , Animais , Bovinos , Interações Hidrofóbicas e Hidrofílicas , Lactoferrina/química , Polimerização , Polímeros/síntese química , Transferrina/química
19.
Chem Pharm Bull (Tokyo) ; 68(6): 534-537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32475857

RESUMO

Hydrophilic polyacrylamide gel-based triazine-type condensing reagents, PAG-Trz-Cl, have been developed. PAG-Trz-Cls were synthesized using a chlorotriazine with an acrylamide moiety, acrylamide, and N,N'-methylenebisacrylamide via both precipitation and solution polymerization. Because PAG-Trz-Cls adequately swell in aqueous media, the amidation between polar carboxylic acids and amines afforded the corresponding amides in good yields.


Assuntos
Resinas Acrílicas/química , Amidas/síntese química , Triazinas/química , Amidas/química , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular
20.
Sci Rep ; 10(1): 8828, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483226

RESUMO

High-performance liquid chromatography (HPLC) is the most common analytical method practiced in various fields and used for analysis of almost all drug compounds in the pharmaceutical industries. During drug development, an evaluation of potential drug interaction with cytochrome P450 (CYP) is essential. A "cocktail" approach is often used in drug development to evaluate the effect of a drug candidate on multiple CYP enzymes in a single experiment. So far, simultaneous analysis of multiple CYP substrates, which have greatly different structure and physicochemical properties, has required organic solvents and mobile phase gradient methods. However, despite the recent emphasis on environmental protection, analytical methods that use only aqueous solvents without the use of organic solvents for separation have not been studied well. This study sought to develop the simultaneous analysis of multiple CYP substrates by using poly(N-isopropylacrylamide) (PNIPAAm)-based temperature-responsive chromatography with only aqueous solvents and isocratic methods. Good separation of multiple CYP substrates was achieved without using organic solvents and any gradient methods by temperature-responsive chromatography utilizing a P(NIPAAm-co-n-butyl methacrylate (BMA))- and P(NIPAAm-co-N-acryloyl L-tryptophan methyl ester (L-Trp-OMe))-grafted silica column. Overall, PNIPAAm-based temperature-responsive chromatography represents a remarkably simple, versatile, and environmentally friendly bioanalytical method for CYP substrates and their metabolites.


Assuntos
Resinas Acrílicas/química , Cromatografia Líquida/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Química Verde/métodos , Clorzoxazona/metabolismo , Cumarínicos/metabolismo , Desenvolvimento de Medicamentos , Mefenitoína/metabolismo , Estrutura Molecular , Fenacetina/metabolismo , Solventes , Especificidade por Substrato , Temperatura , Testosterona/metabolismo , Tolbutamida/metabolismo , Água
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