Preparation of pH-tunable polyelectrolyte complexes of alginate sodium salt and N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride

Abstract

Stimuli-response polymer formulation are of great interest for medicine application. Polyelectrolyte complexes due to their unique ability to change the properties under the external factors represent an example of systems with the feedback mechanism. Interaction of N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC) and alginate sodium salt (ASS) was studied in order to design the stimuli-response complexes. The pH value was found to be one of the most important parameters governing the phase separation in the mixtures of water salt solutions of HTCC and ASS as well as the properties of the resulting complexes. The negatively charged nanoparticles were characterized by the unimodal distribution and had the average sizes 170 ÷ 500 nm depending of composition and pH value; positively charged particles with unimodal distribution were formed only in slightly acidic media. The obtained complexes were stable against the destructive action of salt higher than physiological one. The data demonstrated the potential of the complexes as a promising platform for development of biocompatible, biodegradable and pH-tunable drug delivery systems. Preparation of complexes based on polymers able to undergo pH-dependent ionization with desired properties requires consideration of all factors, ratio of the components and their molecular mass, medium pH and salt concentration.