Polymeric nanoparticles decorated with fragmented chitosan as modulation systems for neuronal drug uptake

This study aimed to modify chitosan (CS) by gamma irradiation and use it as a surface coating of nanoparticles (NPs) fabricated of poly lactic- co -glycolic acid (PLGA) to create mostly biocompatible nanosystems that can transport drugs to neurons. Gamma irradiation produced irradiated CS (CS gamma ) with a very low molecular weight (15.2 - 19.2 kDa). Coating NPs-PLGA with CS gamma caused significant changes in their Z potential, making it slightly positive (from -21.7 +/- 2.8 mV to +7.1 +/- 2.3 mV) and in their particle size (184.4 0.4 +/- 7.9 nm to 211.9 +/- 14.04 nm). However, these changes were more pronounced in NPs coated with non-irradiated CS (Z potential = +54.0 +/- 1.43 mV, size = 348.1 +/- 16.44 nm). NPs coated with CS gamma presented lower cytotoxicity and similar internalization levels in SH-SY5Y neuronal cells than NPs coated with non-irradiated CS, suggesting higher biocompatibility. Highly biocompatible NPs are desirable as nanocarriers to deliver drugs to the brain, as they help maintain the structure and function of the blood-brain barrier. Therefore, the NPs developed in this study could be evaluated as drug-delivery systems for treating brain diseases.