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The aim of the study was to determine immunostimulant properties of chitosan administered alimentary to BALB/c mice. We observed that chitosan feeding effected in activation of cells from the peritoneal cavity. The cells produced less nitric oxide with simultaneous enhanced activity of arginase and higher expression of receptor for IL-4. What is more, chitosan caused increased number of cells expressing...
In clinical practice a lot of natural macromolecular compounds which operation is based on assisting weight loss are used in the obesity treatment. These measures swell in the digestive tract and form the polymer gel system, which has the ability to adsorb up to 5 times more lipids relative to its own weight. When using dietary supplements containing chitosan, sometimes it comes to illness and in...
This paper presents the results of chitosan modification with fatty acids, namely linoleic and oleic acid. We used carbodiimide as the initiator for the reaction of carboxyl and aminoglycoside functional groups. The analysis of infrared spectra confirmed the formation of chitosan derivatives. Their hydrophilic-hydrophobic properties were determined by O/W emulsification and micelles formation in aqueous...
Fenofibrate is an active substance which is well absorbed from the gastrointestinal tract, but it is characterized by limited solubility. Due to a wide spectrum of its pharmacological activity, it would be beneficial to improve its solubility, and thus increase the drug absorption capability. The aim of the study was to investigate the effect of chitosan on the solubility of fenofibrate incorporated...
Due to continued interest in biodegradable polymers, chitosan is one of the most commonly used polymers in the field of control release of active substances. Currently as carriers of drugs, among tablets, or micro spheres transdermal systems, called films, are used. The presented results apply to study a drug release in buffer of pH = 7.2 from chitosan film. To study the kinetics of controlled release...
The thermal degradation behaviour of uncrosslinked and crosslinked chitosan membranes were studied by means of dynamic thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) over the temperature range 25-500ºC in nitrogen atmosphere. Modified chitosan membranes were prepared using a crosslinking method based on covalent crosslinking of chitosan with glutaraldehyde and subsequent...
The new implemented wound dressings should meet several requirements connected with the clinical safety and performance. The series of PN-EN 13726 Standards describes the tests methods for the verification the most important parameters related to mentioned performance and safety of a new designed wound dressing being the base for the risk analysis (according to PN-EN ISO 14971:2009 Standard). The...
Connections of polymers and biopolymers with biologically active compounds are recently the subject of intensive research. Low molecular weight active ingredient combined with a polymer has, in many cases, the modified action. On the other hand, the use of inappropriate polymers can result in incompatibilities drug-polymer. The phenomenon of adsorption of the antibiotic has been studied by the static...
The BCS class II includes drugs with low solubility and high permeability. The substances require modification to increase their solubility in the upper part of the digestive system. Fenofibrate is an example of this class drugs. The aim of the study was to investigate the effect of chitosan on the solubility of fenofibrate incorporated into this polymer carrier. The study investigated fenofibrate...
In the present paper, the results of rheological measurements in solutions of chitosan (Ch) with partially hydrolyzed polyacrylamide (HPAM) are presented. Aqueous acetic acid, lactic acid and aqueous acetic acid/NaCl were used as solvents for chitosan, HPAM and Ch/HPAM solution blends. The criterion of miscibility of solution blends, based on the additivity rule of apparent shear viscosity (ηa) has...
Presented paper discuss the influence of substitution of imidasolium ring on the solubility and structure of chitin. The 1-butyl-3-methyl imidazolium chloride (BMIM)(Cl) and the 1-butyl-2,3- dimethyl imidazolium chloride (BMMIM)(Cl) were used as solvents. These ionic liquids differ by the presence of the substituent in position 2 that causes differences in physical and chemical properties. The surface...
Presented herein are investigations in the preparation of an advanced , human-and environmentfriendly plant protection composition based on selected bioactive biopolymers of the polysaccharide family. In the Institute of Biopolymers and Chemical Fibres the biopolymers were prepared and the biological activity of chitosan in the form of salt and gel and of hemicelluloses (galactoglucomannans) and of...
Ionically crosslinked chitosan membranes were prepared and their swelling behaviour was analysed. Low‑molecular pentasodium tripolyphosphate (TPP) and/or high‑molecular sodium alginate (NaAlg) were used as ionic crosslinkers. Dynamic swelling of noncrosslinked (Ch) as well as singly (Ch/TPP, Ch/NaAlg) and doubly (Ch/NaAlg/TPP) crosslinked chitosan membranes was performed in buffered aqueous solutions...
The study was established to analyze the effectiveness of Reactive Black (RB5) and Basic Green (BG4) dyes adsorption onto chitosan beads and onto chitosan beads cross-linked with glutaraldehyde depending on the initial dye concentration in the solution (1, 5, 100 and 200 mg/dm3). It demonstrated that both the initial concentration of dye in the solution as well as the type of adsorbent affected the...
Degree of deacetylation (DD) is one of the main parameters characterizing chitosan. The most precise measurements of DD require sophisticated equipment (NMR spectrometer), not available at many laboratories worldwide working on chitosan. There is a need for low-cost, simple, yet sturdy and reliable methods and procedures for DD determination. The aim of this work was to test and compare – on the same...
Gels containing lactic acid complexed with chitosan at a stoichiometric ration 1:1 and 2:1 and 5-25% content of polyoxyethylene glycol 200 are able to move from 25 to 30 cm. The addition of glycerol increases the movability gels containing lactic acid complexed with chitosan in a stoichiometric ration 1:1 from 23 cm to 26 cm and at 2:1 ratio from 25 cm to 29 cm. Gels with addition 20-25% poloxamer...
Oligochitosans obtained through degradation of macromolecules of chitosan with a high degree of deacetylation turned out to be biologically active, contributing to an increase of nitric oxide levels in Ehrlich ascites tumor (EAT) cells through inducing expression of the isoform of inducible nitric oxide synthase (iNOS) gene. An increase of NO levels in EAT cells in the presence of the investigated...
Thus ensuring a continuous action of a drug also during daily activity time of a patient is a vital question in gynaecological treatment. The main problem in applied therapies is to maintain the continuity of treatment during 24 hours. The addition of 5-25% glycerol or 1,2-propylene glycol decreases the pH of investigated gels with calcium alginate to 4.20 to 4.88 (1:1) and 3.69 to 4.19 (2:1); 4.29...
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