Efficacious cellular codelivery of doxorubicin and EGFP siRNA mediated by the composition of PLGA and PEI protected gold nanoparticles.

ABSTRACT

This study reports the simultaneous delivery of EGFP siRNA and the chemotherapeutic drug, doxorubicin by means of the composition that results from the electrostatic interaction between positively charged siRNA-complexes of gold nanoparticles (AuNPs) capped with PEI, 25kDa (P25-AuNPs) and negatively charged carboxymethyl cellulose formulated PLGA nanoparticles loaded with doxorubicin. The nanoparticles and their facile interaction were studied by means of dynamic light scattering (DLS), zeta potential, transmission electron microscopic (TEM) measurements. The flow cytometric and confocal microscopic analysis evidenced the simultaneous internalization of both labelled siRNA and doxorubin into around 55% of the HeLa cancer cell population. Fluorescence microscopic studies enabled the visual analysis of EGFP expressing HeLa cells which suggested that the composition mediated codelivery resulted in a substantial downregulation of EGFP expression and intracellular accumulation of doxorubicin. Interestingly, codelivery treatment resulted in an increased cellular delivery of doxorubicin when compared to PLGA-DOX alone treatment. On the other hand, the activity of siRNA complexes of PEI-AuNPs was completely retained even when they were part of composition. The results suggest that this formulation can serve as promising tool for delivery applications in combinatorial anticancer therapy.