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A vapour permeation of water and ethanol through homogenous chitosan and alginate membranes was investigated. The influence of the polymer matrix and crosslinking agents, and measurement protocol on the transport properties were discussed. The conducted experiments showed the greater separation factor, better stability and resistant to solvents for chemically crosslinked membranes. On the other hand,...
Synthesis of nanocomposite chitosan-TiO2 have been done. Nanocomposite made of chitosan was isolated from crab shell namely α-chitosan and squid pens as β-chitosan. Nanocomposite was synthesized by combining the function of chitosan as supporting material with TiO2 particle that have high photocatalytic activity. The nanocomposite characterized by FTIR and SEM/EDX analysis show the functional groups...
In the present study, the results of viscosity measurements in dilute solutions of chitosan (Ch) with hyaluronic acid (HA) are presented. Chitosan is blended with hyaluronic acid in aqueous 0.1M CH3COOH/0.2M NaCl and 0.3M NaCl respectively, or with the addition of HEPES. Viscosity measurements of dilute polymer solution were carried out in an Ubbelohde capillary viscometer. The intrinsic viscosity,...
In this study, we investigated the effectiveness of Reactive Black 5 dye adsorption onto chitin and chitosan flakes. Adsorption capacity of chitin and chitosan, optimal pH of the adsorption process and reaction equilibrium time were determined. Results achieved were described with Freundlich, Langmuir and double Langmuir models. The pH value ensuring the highest dye adsorption effectiveness onto chitosan...
The aim of the present study was to increase the solubility of ibuprofen. Among the methods to increase the solubility selected solid dispersions of the drug with the polymer. Chitosan was used as the polymer. Solid dispersion obtained. Ibuprofen was incorporated into the chitosan type 652 with molar masse chitosan Mη = 429 kDa. Solid dispersions were prepared by using different ratios of ibuprofen...
Gold nanoparticles (AuNPs) were synthesized, in the absence of any reducing agent, using ionizing radiation or ultrasound in aqueous solutions of chloroauric acid (HAuCl4). Chitosan (average molecular weight 158 kDa, degree of deacetylation 90 %) was used as a stabilizing agent. Both techniques yielded AuNPs which were stable in solution at RT for at least 3 months after synthesis. UV-Vis spectroscopy...
The aim of this work was to investigate the effect of different nanoparticles (TiO2 and organically modified montmorillonite MMT) on thermal stability of chitosan thin films (obtained by casting) and to compare with previously studied- CuO and Ag effect. Thermal degradation was carried out in air atmosphere at 140°C up to 100 hours. Various functional groups of chitosan have a different susceptibility...
The aim of this work was to a study various adsorption processes of methyl violet (model compound of aniline dye) on chitin and chitin deacetylation products. Two types of adsorption processes - batch and continuous - were tested. Results illustrated that raw chitin is an effective adsorbent for methyl violet and the adsorption activity of chitin deacetylation products strongly decrease with increasing...
The damage to the central nervous system is one of the most difficult cases of trauma to treat. Over the last few years, increasing attention has been focused on the development of strategies based on biomaterials for regeneration and repair of the spinal cord injury. In particular, materials in the form of hydrogels based on chitosan are being actively investigated due to their intrinsic properties...
The aim of the study was to evaluate the effect of changing the concentrations of chitosan on the rheological properties of the obtained formulation. Hydrogels were prepared with 1% hydrocortisone containing 4% sodium carboxymethylcellulose with the addition of chitosan, propylene glycol-1,2 or polyethylene glycol 400 and glycerol or paraffin. The concentration of chitosan and excipients affects the...
The cytotoxicity of chitosan with polyvinox (PCH) and crosslinked chitosan (CH) was studied and analyzed. Cell viability was determined by thiazolyl blue formazan (MTT) assay and cell morphology observations were carried out during cell culturing and MTT tests. Crosslinked chitosan was used as a protective foil (scaffold) for skin wounds. Studies in vitro and the other obtained in this work results...
Chemically and physically crosslinked chitosan hydrogel membranes were obtained by treatment of chitosan (Ch) with glutaraldehyde (GA) and with GA and subsequently with sodium tripolyphosphate (TPP). The formation of covalent and ionic crosslinks between Ch, GA and ionic TPP was confirmed by FTIR spectroscopy. The studies of dynamic swelling behaviour of synthesized membranes in buffer solutions of...
Aim of the work was to prepare a method of producing chitosan and chitosan-alginate nanoparticles designed for the modification of textile cellulosic products in hygiene and medical application. Spectrophotometry was used in the estimation of the prepared nanoparticles; analyzed, too, was the particle size and antibacterial and antifungal activity.
Surface properties of composites containing chitosan (Ch), poly(vinyl alcohol) (PVA) with hydroxyapatite (HAP) were investigated by contact angle measurements and atomic force microscopy (AFM). Thin films of Ch/HAP and Ch/PVA/HAP composites have been formed by casting methods from acetic acid solutions. Measurements of the contact angle for diiodomethane (D), and glycerol (G) on the surface of chitosan...
Pervaporative separation properties of crosslinked chitosan and alginate membrane on ethanol-water mixture at room temperature was studied. The influence of crosslinking agents on the separation properties were discussed. Selected crosslinking agents were affected differently on used polymer matrices. The better separation properties were obtained for membranes crosslinked by phosphoric (V) acid....
In the present study the results of rheological measurements and atomic force microscopy (AFM) of polymer composites with montmorillonite (MMT) are presented. Chitosan is blended with synthetic polymers and inorganic additives in acetic acid solution and this solution is cast to prepare the mixture film. Flow measurements were made on a Bohlin Visco 88 rotary viscometer in the temperature range 25ºC-40ºC...
Atmospheric-pressure air and nitrogen plasmas generated by surface dielectric barrier discharges have been used to incorporate new functionalities at the surface of polypropylene nonwoven fabric. The main goals were to activate the polymer surfaces for subsequent immobilization of chitosan from water solution without using any crosslinking and wetting agents. The samples were analyzed by diffuse reflectance...
The aim of this work was to study the properties of methylcellulose hydrogels with supplements containing chitosan and 1% hydrocortisone. Depending on the composition of the substrate, gels are characterised by a variety of pharmaceutical availabilities. Increasing the concentration of chitosan has an influence on increasing the viscosity, hardness, and cohesiveness of the tested gels.
Combinations of polymers and biopolymers of biologically active compounds in the last period have been the subject of intensive research. The active substance linked to a polymer often has a modified function and sometimes no action. On the other hand, the use of unsuitable polymers may result in a type of mismatch of drug-polymer. The aim of the study was to examine whether the active substance ketoconazole...
Chitosan is widely applied in biomedical and cosmetic fields. For this reason, there is a need to modify this biopolymer to achieve new properties of chitosan-based materials. The properties of chitosan can be modified by several cross-linking methods. In this work, we used the chemical cross-linking of chitosan with tannic acid, after which cross-linked chitosan was shaped into a 3D structure by...
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