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In this paper, nanocomposite hydrogel beads were prepared through combining carboxymethyl cellulose (CMC), starch, and ZnO nanoparticles (ZnO-NPs), as well as physical cross-linking with FeCl3. The obtained nanocomposite hydrogel beads were used as a potential candidate for controlled release of anticancer drug doxorubicin (DOX). The nanocomposite hydrogel beads were characterized using FT-IR, XRD, UV-vis, SEM, EDX, TGA and DSC. In addition, gel content, swelling/de-swelling properties, and drug release of the samples were evaluated. The swelling and drug release profiles revealed that the amount of drug released and swelling of the hydrogels depended on the CMC content, pH, and ZnO nanoparticle content. Prolonged and more controlled drug releases were observed for ZnO nanoparticle containing CMC/Starch beads, which increased with the rise in ZnO nanoparticle content. The cytotoxicity of the samples was confirmed using human colon cancer cells (SW480).In this contribution, a novel cellulose acetate modified with dopamine (CA-DA) membrane material was designed and prepared by a two-step route consist of chlorination and further substitution reactions. The chemical structure of the prepared CA-DA material was determined by FTIR and 1H NMR, respectively. The CA-DA ultrafiltration membrane was subsequently fabricated by the scalable phase inversion process. Compared with cellulose acetate membrane as the control sample, the introduction of dopamine improved the porosity, pore size and hydrophilicity of the CA-DA membrane, which was helpful to the water permeability (181.2 L/m2h) without obviously affecting the protein rejection (93.5%). According to the static protein adsorption and dynamic cycle ultrafiltration experiments, the CA-DA membrane displayed persistent antifouling performance, which was verified by flux recovery ratio, flux decline ratio and filtration resistance. Moreover, the water flux recovery ratio of the CA-DA membrane was retained at 97.3% after three-cycles of BSA solution filtration, which was much higher than that of the reference CA membrane. This new approach provided a long life and excellent ultrafiltration performance for polymer-based membranes, which has potential application prospects in the field of separation process.In order to exploit an abundant and cheap carbon source for poly(3-hydroxybutyrate) (PHB) production, the rice husk was pretreated with dilute sulfuric acid and steam flash-explosion to enhance the enzymatic saccharification. The yield of reducing sugars of pretreated rice husk hydrolysate came up to 266.5 mg/g rice husk, much higher than that of untreated rice husk hydrolysate (72.67 mg/g rice husk). This result indicated that the pretreatment can significantly enhance the yield of reducing sugars. Then the hydrolysate was used as a sole carbon source for PHB production by using Cupriavidus necator. Response surface method was used to optimize the fermentation conditions. Chloroquine research buy Under optimum fermentation conditions (carbon source, 31.81 gL-1; nitrogen source, 1.8 gL-1; pH-value, 7.0; temperature, 27.1 °C), the PHB yield was 5.0 gL-1, which was in good agreement with the predicted value.Hydrogels can be used as bioactive dressings, which outperform traditional dressings and are widely used in wound hemostasis and healing. However, it is still a challenge to develop a hydrogel with good stability and strong mechanical properties for wound hemostasis and healing. Herein, we developed a novel composite polysaccharide hydrogel from fenugreek gum and cellulose. Fenugreek gum was combined with cellulose through hydrogen bonding to form a hydrogel to improve the mechanical properties of the composite hydrogel. The composite hydrogel had a porous structure, thermal stability, good water absorption and a sustained release effect. Furthermore, the composite hydrogel demonstrated good biocompatibility in vitro and in vivo. Notably, the superior performance of wound hemostasis and healing has been confirmed. Our results indicated that the composite hydrogel was a promising medical dressing and had the potential to promote wound healing.A film of chitosan, gelatin and liposome has been designed for dermatological applications. Several adaptations were required throughout development to facilitate in vitro analysis, physicochemical characterization and biocompatibility evaluation. The final version of the film was characterized by differential scanning calorimetry, evaluation of swelling and scanning electron microscopy. The biocompatibility of the film was assessed by investigating cellular parameters of three types of human cells by direct contact or through films extracts I) primary culture of adipose-derived mesenchymal stromal cells (ADCSs) and melanoma cell lines were used to test cell adhesion and morphology by direct cell culture on the material; II) ADSCs and immortalized keratinocytes were used in cell viability assay using different films extracts. The film showed physicochemical characteristics that favored cellular input, being suitable for in vitro analysis, which allowed its biocompatible characteristics such as the absence of toxicity to be verified without causing significant morphological changes in ADSCs and melanoma cell line. Altogether, these results suggest that the material has a potential application for drug delivery and promotion of skin tissue repair and is therefore worthwhile for further investigations using preclinical models to cover dermal lesions.The goal of this study was to reveal how the chemical modification, succinylation in this case, of the wide-pore serum-albumin-based cryogels affects on their osmotic characteristics (swelling extent), biodegradability and ability to be loaded with the bactericide substance - dioxidine, as well as on its release. The cryogels were prepared via the cryogenic processing (freezing - frozen storage - thawing) of aqueous solutions containing bovine serum albumin (50 g/L), denaturant (urea or guanidine hydrochloride, 1.0 mol/L) and reductant (cysteine, 0.01 mol/L). Freezing/frozen storage temperatures were either -15, or -20, or -25 °C. After defrosting, spongy cryogels were obtained that possessed the system of interconnected gross pores, whose shape and dimensions were dependent on the freezing temperature and on the type of denaturant introduced in the feed solution. Subsequent succinylation of the resultant cryogels caused the growth of the swelling degree of the pore walls of these spongy materials, resulted in strengthening of their resistance against of trypsinolysis and gave rise to an increase in their loading capacity with respect to dioxidine. With that, the microbiological tests showed a higher bactericidal activity of the dioxidine-loaded sponges based on the succinylated albumin cryogels as compared to that of the drug-carriers based on the non-modified protein sponges.Type 2 diabetes is a multifactorial disease and drugs with multifunctional properties are required. The peptide, SQSPA, was reported to be a potent and gastrointestinally stable α-glucosidase inhibitory peptide. In this study, the structure-activity relationship of this peptide was studied using alanine scanning. Four analogs; AQSPA, SASPA, SQAPA and SQSAA were designed and investigated for multifunctional antidiabetic effects. Molecular docking studies on human dipeptidyl peptidase-IV (DPP-IV) suggested that the binding affinities were in the order; AQSPA>SASPA>SQSPA>SQSAA>SQAPA while for in vitro DPP-IV inhibitory activity, it was SQSPA>SQSAA>AQSPA>SASPA>SQAPA. Enzyme kinetic studies revealed that the peptides are uncompetitive inhibitors with the exception of SQSAA and SQSPA. In 3T3-L1 differentiated adipocytes, SASPA was the only analog that significantly (p less then 0.05) reduced and prevented lipid accumulation and did not induce cytotoxicity to differentiated 3T3-L1 cells. All peptides, especially SASPA scavenged methylglyoxal and peroxyl radicals thereby preventing advanced glycosylated end products formation and oxidative stress. The nitric oxide scavenging activity of all peptides was comparable to IPI and glutathione. Findings indicate that the amide side chain of Q2 is probably the most critical functional group for modulating the multifunctional antidiabetic effects of SQSPA while SASPA has been identified, as a novel peptide with enhanced multifunctional antidiabetic activity.Self-assembly behavior of charged-starches significantly influenced core-shell structures of layer-by-layer assembled particles. In this study, insulin (IN)-loaded nanoparticles with structured shell features were fabricated to investigate how the interactions of carboxymethyl starch (CMS) with spermine-modified starch (SS) influenced IN release properties of the particles (IN/CMS/SS/CMS) within the gastrointestinal tract (GIT). Results indicated that the assembly action of CMS and SS could be controlled by simply tailoring the ratio of CMS/SS content. An intermediate CMS/SS ratio (14) was required to construct nanoparticles with compact shell structure and desirable IN release properties in the colon (74.23%). However, a higher CMS/SS ratio (12) yielded particles with loose shell structure and an excessive IN release in the upper GIT (58.89%), and a lower CMS/SS ratio (18) rather resulted in particles with higher compactness shell structure along with limited IN release in the colon (29.01%). The interactions between CMS and SS should be the key factor influencing core-shell structures and in turn the IN-release properties of the carrier. The shell structure and release properties of layer-by-layer assembled particles could be tailored by controlling the interactions between starches.Although research on phytochemicals has been a hot topic due to positive effects on human health, modification of starch with phytochemicals has been limited. In the present work, cassava starch-ferulic acid (CS-FA) complexes were acquired using different times of mechanical activation via stirring ball milling, and their characterization and physicochemical properties were investigated. Scanning electron microscopy showed the broken structure of native cassava starch, but the smooth structure of CS-FA complexes. The X-ray diffraction indicated that the C-type crystalline structure of native cassava starch completely disappeared with the increase time of mechanical activation. The complexation was characterized by Fourier transform infrared (FT-IR) spectroscopy and Solid carbon nuclear magnetic resonance (13C NMR) studies. The TGA analysis showed that the thermal stability was decreased by mechanical activation, but it could be improved with the existence of ferulic acid. The solubility of CS-FA complexes increased with increasing of the time by mechanical activation. Therefore, mechanical activation is considered a suitable method for preparing CS-FA complexes. As a new material with considerable antioxidant activity, it would be a great potential for CS-FA complexes in functional food, biomedical materials, and cosmetic products.Hydrogel finds an interesting candidate in the biomedical field due to their unique properties such as biocompatibility, biodegradability, soft as tissue etc. In the reported research article natural biopolymer i.e. chitosan based hydrogel was developed via condensation reaction with cuminaldehyde. Chitosan and cuminaldehyde were used for the gel formation by covalent bonding between free amino group and carbonyl group of chitosan & cuminaldehyde respectively. A series of hydrogel has been developed by taking different concentration of cuminaldehyde (6-10 mmol). Chemical structure of the synthesized hydrogel was further confirmed by FTIR. The surface morphology of the synthesized hydrogel was confirmed from the scanning electron microscopy (SEM). Prepared hydrogel was swelled very fast similar to the super-porous hydrogel along with rapid self-healing property which is confirmed by rheology statistics. Mechanical strength of the hydrogel was investigated from the rheology analysis and demonstrates good mechanical properties i.

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