Formulation of siRNA nanoparticles, transfection and enhanced adhesion -penetration in nasal mucosal tissue

This study investigates the efficacy of trimethyl chitosan (TMC) nanoparticles (NPs) for the delivery of small interfering RNA (siRNA) targeting the EGFR gene, with a focus on optimizing complexation efficiency, release profiles, and transfection efficiency, as well as investigating mucoadhesion and mucopenetration properties. TMC nanoparticles were formulated at various siRNA:TMC weight-to-weight (w:w) ratios and assessed for binding efficiency, release in the presence of heparin, physical properties, cytotoxicity, and EGFR knockdown efficiency in HeLa cells. The integration of additives such as dextran sulfate (DS), tripolyphosphate (TPP), and hyaluronic acid (HA) was explored to enhance nanoparticle performance. Results demonstrated that higher TMC ratios improved siRNA binding and reduced release rates, with additives further stabilizing the nanoparticles. The optimized formulations showed high cell viability and significant EGFR silencing, indicating effective transfection. Mucoadhesion and mucopenetration two-photon microscopy studies on rabbit nasal mucosa confirmed the superior performance of TMC nanoparticles over free siRNA, highlighting their potential for non-invasive gene therapy applications.