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Biodegradable nanoparticulated carriers have important potential applications for administration of therapeutic proteins and peptides. Chitosan based nanoparticles have attracted attention due to their biological properties such as biodegrability and biocompatibility. However, chitosan nanoparticles are not stable in colloid form. Therefore, to increase the stability of these particles is an important...
In this study, the structure of hydrogel chitosan membranes was investigated. To determine the structure of hydrogel membranes the Differential Scanning Calorimetry (DSC) was used. On the basis of DSC spectra the enthalpy of the character of water in the structure were determined.
Commonly applied drug forms tend to leave the vagina when the patient assumes an upright position. Permanent contact of the drug form with the vaginal mucosa during daily activities of the patient is an indispensable condition for 24-hour therapy. This condition may be fulfilled by drug forms with high ability to adhere to vaginal mucosa. The investigations demonstrated that the thermosensitive polymer...
There is endless and growing demand on a novel and innovative wound dressings, which except basic protective performance accelerate the process of wounds healing and/or replace the patient skin function. The studies on the new wound dressings result from the need of the quick and effective treatment of wounds, such as: having no tendency to heal, posttraumatic wounds, scalding wounds, ulcerations...
Recently, the market of medical devices shows serious need for wound dressings for first aid and temporary traumatic wounds. Such a wound dressing should show primarily the hemostatic effect and antibacterial activity allowing protection against infection. Tromboguard® topical wound dressing is a three-layer dressing with active layer. It contains chitosan, sodium alginate/calcium alginate with addition...
Modified chitosan hydrogel membranes were prepared using glutaraldehyde (GA) and sodium citrate (NaCIT) as crosslinking agents. Molecular and supermolecular structure analyses of unmodified and modified chitosan membranes have been conducted by FTIR and X-ray spectroscopy. FTIR results showed covalent and ionic crosslinks formation between chitosan (Ch) and GA or simultaneously Ch, GA and NaCIT. The...
Unmodified (Ch) and ionically crosslinked with sodium tripolyphosphate (Ch/TPP) chitosan membranes were prepared. Various crosslinking conditions (pH, crosslinking time) were applied. Differences in membrane molecular structure was examined using FTIR spectroscopy. Scanning electron microscopy (SEM) coupled with Energy Dispersive X-Ray (EDX) Spectrometer as well as atomic force microscopy (AFM) were...
Investigations are presented in the preparation of composite dressing material based on two biopolymers -chitosan and sodium alginate with the addition of sulfanilamide as medication designed for the healing of bedsores. The dressing was prepared in the form of film. The biopolymers used in the construction of the film make the dressing biodegradable and resorbable in the wound’s environment. Mechanical...
In the present paper, the results of viscosity measurements in dilute solutions of microcrystalline chitosan (MCCh) with poly(vinyl alcohol) (PVA) of different degrees of hydrolysis are presented. Microcrystalline chitosan is blended with poly(vinyl alcohol) in aqueous 0.1 MCH3COOH/0.2 M NaCl. Viscosity measurements of dilute polymer solution were carried out in an Ubbelohde capillary viscometer....
The aim of this study was to develop a preparation method of porous chitosan structures, in the electrolysis of the chitosan solution in acetic acid. Chitosan in aqueous acetic acid is a polyelectrolyte. During the constant flow of electric current through this system, pure chitosan begins to accumulate on an anode, in the form of porous hydrogel layers. The addition of hydroxyapatite (HAp) to the...
The study was undertaken to analyze cyclic sorption and desorption of four reactive dyes: Reactive Yellow 84, Reactive Red 11, Reactive Black 5 and Reactive Black 8. onto chitosan beads. In all experimental series, dye and sorbent concentrations were constant and reached 50 mg/dm3 and 1 mg d.m./dm3, respectively. Determinations were conducted to investigate the effect of the sorbent on the effectiveness...
Gels containing lactic acid complexed with chitosan at a stoichiometric ratio 1:1 and 2:1 and 5 - 25% content of polyoxyethylene glycol 200 reveal pH from 2.5 to 4.6. The addition of 20 – 25% poloxamer 407 increases the pH to 4.55 to 5.30 for 1:1 gels and 4.00 to 4.85 for 2:1 gels. The addition of 0.5% polyvinyl alcohol decreases the pH of the investigated gels to 4.00 to 4.55 for 1:1 gels and 3.85...
Preliminary studies of proliferation of Ehrlich ascites tumor (EAT) cells and normal mammary gland epithelial cells have demonstrated the process to be inhibited by degradation products of microcrystalline chitosan, i.e. oligomers. Inhibition of proliferation has been also accompanied by a decreased activity of the M2 pyruvate kinase (PK) isoenzyme in nucleoplasm, what may indicate the role of this...
The aim of the study was to prepare a bi-polymer drug carrier composed of chitosan pellets (CS) coated with polylactide shell (PLA) providing prolonged model drug – salicylic acid (SA) release into phosphate buffer of pH = 7.2. Pellets were obtained through a coacervation followed by a freeze-drying process. In a terms of model drug loading, porous pellets were impregnated with a SA solution under...
In order to improve the properties of their individual components, the compositions of dibutyrylchitin (DBC) and aliphatic polyesters (PCLG) were prepared and examined. The studied systems are homogeneous in a wide range of composition and molar masses of their components. The homogeneities of the blends made it possible to form smooth and transparent films, which were investigated by mechanical testing...
In the present paper the degradation of chitosan and its blends with hydroxyapatite, nanoclay and nanosilver as well as the impact of those nanofillers added to chitosan on its decomposition at high temperatures are studied. The applied films of thickness 50 μm were obtained by casting the acidic solutions: chitosan and its blends with hydroxyapatite, nanoclay and nanosilver. To mix solutions with...
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