Modulating drug delivery with nano-selenium capped chitosan reverse micelles for anticancer potential

Combining nanoparticles with biopolymer protective coatings offer an appealing cancer treatment strategy. This study develops chitosan (CS) coated selenium (Se) nanocarriers via reverse micellar method using surfactants such as sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and N-cetyl-N,N,N-trimethylammonium bromide (CTAB) to enhance the sustained release of daunorubicin (DNR) and to improve the stability of drug carriers. The chemically reduced Se nanoparticles aggregated into elongated rod shapes, approximately 60 nm in diameter, and were coated with CS to form a protective layer that sustained the drug release. Zeta potential measurements revealed that CS coating increased the surface charge of Se nanoparticles, with values of 33 ± 6.1 mV for CTAB system and 30 ± 5.7 mV for AOT systems. Additionally, AOT resulted in higher encapsulation efficiency (70 %) compared to CTAB (62 %). DNR drug release at pH 5.4 showed a significantly higher cumulative release (88 %) compared to pH 7.4 (75 %), demonstrating pH-dependent release behavior. The CS coating acts as a gatekeeper, regulating the release of DNR from Se nanoparticles. In vitro studies showed that both CS-CTAB-Se@DNR and CS-AOT-Se@DNR carriers exhibited higher cytotoxicity and increased ROS generation compared to bare Se nanoparticles. These findings highlight the potential of CS-Se@DNR nanocarriers as an effective strategy for cancer treatment.