Interests of chitosan nanoparticles ionically cross-linked with tripolyphosphate for biomedical applications

The process of ionic gelation is one of the easiest ways to develop chitosan nanoparticles reported so far in the literature. Its success is mainly due to its one-shot synthesis, and to the mild environment required to produce the nanoparticles. The nanoparticle formation all along this process has been therefore thoroughly studied to lead to particles with a nanometric size, a narrow size distribution, and a spherical shape that are ideal for biomedical uses. The purpose of this review is to compile the biomedical applications that have been considered in the literature for these chitosan nanoparticles prepared by ionic gelation using tripolyphosphate as ionic agent. Their intrinsic biological properties such as non-toxicity, antimicrobial activity, mucoadhesivity and haemocompatibility are firstly discussed and compared to those of chitosan solutions. Then, the different bioactive species (drugs and biomacromolecules) incorporated in these chitosan nanoparticles, their maximal incorporation efficiency, their loading capacity, and their principal associated biomedical applications are presented.