Analysis of the Rheological Behavior of Solutions of Some Polysaccharides in Order to Optimize the Concentration of the Polymer in the Solution Used for the Preparation of Soft Dosage Forms in the Form of Protective Wound Coatings

The work is devoted to the analysis of solutions of some polymers in order to optimize the concentration, which ensures the production of protective film materials with the necessary characteristics. The polysaccharides such as pectin, chitosan, the sodium salt of chitosan succinyl and the sodium salt of carboxymethylcellulose were used as the basis for the creation of materials in this work. The conducted rheological studies suggest that solutions of polysaccharides, depending on the polymer concentrations, have different degrees of structure and fluidity. Solutions with concentrations up to C_e behave like Newtonian liquids. Solutions with concentrations between C_e and C_gel are like pseudoplastic liquids. Solutions with higher concentrations behave like elastic-viscous gels. The polymer concentration in solution used in the process of forming a film coating fundamentally affects a number of physicochemical and physicomechanical characteristics of films. In order for film coatings to be characterized by maximum strength and elasticity, good sorption capacity and controlled drug yield, they must be formed from a semi-diluted solution with a concentration of С_е < С < С_gel.