Octahydrogenated retinoic acid-conjugated glycol chitosan nanoparticles as a novel carrier of azadirachtin: Synthesis, characterization, and in vitro evaluation

Environment-friendly and controlled release formulation is highly promising for reducing environmental pollution and achieving the most effective utilization of pesticides. As a novel “green” nanocarrier of pesticides, amphiphilic self-assembled nanoparticles were prepared by chemical conjugation of octahydrogenated retinoic acid (OR) to the backbone of glycol chitosan (GC). In aqueous media, the synthesized OR-GC conjugates formed nanosized particles with a diameter of 257 nm. Hydrophobic azadirachtin (AZA) was efficiently loaded into the OR-GC nanoparticles at a feed weight ratio of up to 1:4 using a simple dialysis method, the maximum drug-loading efficiency of which was 74%. AZA-OR-GC (25 wt %) nanoparticles also showed sustained release of the incorporated AZA (65% of the loaded dose was released in 7 days at 27 °C in phosphate-buffered saline; pH 7.2). Cytotoxicity tests and cell cycle arrest assays confirmed that OR-GC exhibits good biocompatibility; AZA-OR-GC (25 wt %) nanoparticles also showed favorable inhibition of cell proliferation in Sl-1 cells compared with free AZA in organic solvents. Overall, controlled release AZA-OR-GC may be a promising environment-friendly formulation for integrated pest management. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51 , 3932–3940