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Chitosan as a dietary supplement has been used in the treatment of obesity due to its capability of binding bioactive compounds. A molecule of a cationic polymer, such as chitosan, may bind acid drugs. The aim of the study was to determine the binding capability of Ketoprofen and Naproxen sodium salt by chitosans contained in weight-loss supplements. The drug absorption was investigated by means of...
Peripheral nerve injuries are one of frequent cause of disability. Results of surgical procedures are not still completely satisfactory, though fast development of microsurgical technician improve their efficiency. One of the major problems in surgical treatment of the peripheral nerve injuries is ends coaptation in the case of large loss of nerve tissue. And so finding substitute implants not rejected...
The results of physical modification of dibutyrylchitin (DBCH) for the purpose of improvement of its imperfect mechanical properties are presented. Thus, the novel blends of DBCH and biodegradable aliphatic copolymer derived from ε-caprolactone, L-lactide and glycolide (PCLG) in various proportions were prepared and examined. DBCH/PCLG blends with PCLG contents between 6 - 50 wt% were successfully...
Both 1:1 pre-metallised acid dyes and pre-coppered direct dyes, but not 1:2 pre-metallised acid dyes, have been shown to readily dye chitin and chitosan from neutral dyebaths. With the 1:1 pre-metallised acid dyes the addition of neutral electrolyte increases the uptake of dye, indicating that electrostatic forces of attraction are not involved in the adsorption process. A mechanism of dyeing is proposed...
Results of the earlier studies suggested an involvement of ciliates Eudiplodinium maggii in the digestion and metabolism of chitin in the rumen. In the presented paper we described the results on the preliminary identification and characterization of chitinolytic enzymes of this ciliate as well as the method of their purification. The protozoal crude enzyme preparation was used as source of enzymes,...
Abstract. Polymer films were made of different biodegradable materials. Solid support of model active substance (salicylic acid) was unmodified and modified (crosslinked with glutaraldehyde) chitosan and outside layers were polylactid acid (PLA). The aim of the study was to obtain the controlled release kinetics of active substance, in medium of pH 5.6 which is similar to conditions occurring on the...
Bacterial vaginitis affects women of all age groups. Numerous recurrences of the condition are widely discussed by clinicians. Traditional therapeutic schemes recommended by world treatment centres and health organizations do not bring satisfactory results. Their effects are hampered by numerous anatomic and physiological conditions which do not facilitate prolonged contact of the drug with the application...
With the increasing amounts of recombinant proteins production the problem of effective purification of produced proteins became one of major topics for research nowadays. Affinity chromatography proved to be the most dominant method for this aim and application of chitin based affinity sorbents in combination with use of chitin-binding domain as an affinity tag for purification of recombinant proteins...
Differential thermal analysis was carried out over the range of –190 ÷ 400 °С on six samples of chitin from shells of industrial crabs of various species. All samples of the chitin have several relaxation transitions of endothermal character (g1-, g2-, β- and γ-).
Anatomical and physiological conditions in the vagina do not facilitate easy application of the drug neither its maintenance on the site of application. Insufficient duration of the drug’s contact with vaginal mucosa does not provide adequate pH conditioning the physiological biocenosis of the organ. Gels containing lactic acid complexed with chitosan at a stechiometric ration 1:1 and 2:1 and 5 -...
L-S-nitrosocysteine formation in EAT tumor cells and normal CRL-1636 cells incubated with microcrystalline chitosan was confirmed by RP-HPLC. The metabolite was identified based on UV-VIS spectra. The formation of L-S-nitrosocysteine in EAT tumor cells contributes to decreasing the level of L-cysteine in these cells. L-cysteine as an effector of the bifunctional M2 isoenzyme of pyruvate kinase (PK)...
The salts of dichloroacetic acid were obtained from chitosans of different deacetylation degrees (69÷97%) and viscosity-average molecular weights (61÷327 kDa). The mole ratio of dichloroacetic acid to amine groups was 1. The chemical and physical properties of the salts were evaluated by determining the dry weight, the content of ash, acid, insoluble substances, kinematic viscosity, and pH. The studied...
The aim of the study was to develop preparation methods of porous chitosan structures and to investigate their morphological properties as well as the kinetics of model substance release (salicylic acid). Chitosan scaffolds were generated using the liophylisation method and the systems obtained were saturated with hydroxyapatite and salicylic acid. Microscopic investigations (optical and electron...
The ionically crosslinked membranes were prepared of chitosan (Ch) and trisodium citrate (Ch/CIT). The characteristics of the state of water in crosslinked and uncrosslinked chitosan membranes with different water content was performed by differential scanning calorimetry (DSC). The kinetics of water swelling in Ch and Ch/CIT membranes were also studied. Conclusions concerning effect of ionic crosslinking...
The biodegradable blends of chitosan and starch with different component ratios were prepared by casting method. Obtained thin films were UV-irradiated (λ = 254 nm) and changes in chemical structure were monitored using FTIR and UV-Vis spectroscopies. It was found that the chitosanstarch blends were more susceptible to UV irradiation comparing to pure starch specimen. FTIR spectra of blends suggest...
In the paper the thermal deactivation of chitin deacetylase separated from Absidia orchidis vel coerulea was investigated. Experiments were carried out at a temperature of 50ºC up to 24 hours. Three mechanisms of deactivation were tested: irreversible first-order, reversible firstorder, and three-parameters phenomenological model. It was found that the last one gave the best approximation of the deactivation...
The study was aimed at determining the effectiveness of reactive dye RB5 removal in the adsorption process onto chitin and chitosan as affected by the quantity of an adsorbent and pH value of the solution. The experiment was conducted at two concentrations of a sorbent, i.e. 1 and 5 mg d.m./dm3 and at three values of the reaction, i.e. pH 3.0, pH 5.0, and pH 9.0. The kinetics of RB5 sorption onto...
Polysaccharides are macromolecular polymers that manifest ability toward the forming of fibres, film and coatings. Some of their specific properties like biodegradability and biocompatibility make them suitable for medical application. Chitin, chitosan and alginates are basic polymers mostly used in the preparation of medical biomaterials. In the Institute of Biopolymers and Chemical Fibres (IBWCh)...
Ionically crosslinked one‑component chitosan (Ch), two‑component chitosan/sodium alginate (Ch/NaAlg) and chitosan/pentasodium tripolyphosphate (Ch/TPP) membranes as well as three‑component chitosan/sodium alginate/pentasodium tripolyphosphate (Ch/NaAlg/TPP) membranes were prepared. Formation of ionic interactions between Ch and NaAlg and/or TPP was confirmed by FTIR analysis. An effect of a crosslinking...
In the present paper the Authors analyse the experimental results of a model drug (ibuprofen) release approximated with three commonly used semi-empirical models: Korsmeyer-Peppas, first order kinetics and Gallagher-Corrigan equation. Drug carriers in the form of films composed of chitosan matrix and polylactide microparticles were produced by ultrasonic emulsification with solvent evaporation followed...
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