A smart dual-responsive nanoplatform for delivery of prochloraz for the control of rice blast disease

Nano-controlled release formulations present a promising strategy to mitigate pesticide losses and enhance efficiency. In this study, a pH and GSH-responsive nanoplatform using mesoporous organosilica nanoparticles (MONs) as a carrier and poly(tannic acid) (PTA) as capping agent was established for controlling prochloraz (Pro) release. The obtained Pro@MON@PTA was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA). The results indicate the successful preparation of Pro@MON@PTA nanoparticles, featuring uniform particle size (190 nm), excellent dispersibility, and a prochloraz loading efficiency of 17.2%. Evaluation of contact angle and adhesion work demonstrated superior adhesion of MON@PTA to rice leaves compared to MON. Controlled release studies revealed dual-responsive release properties of Pro@MON@PTA to acid and GSH. Additionally, photostability testing indicated effective ultraviolet light shielding by the carrier, reducing prochloraz degradation under irradiation. Bioassay results indicated equivalent fungicidal activity against Magnaporthe oryzae between Pro@MON@PTA and prochloraz technical and prochloraz EW after a 7-day treatment. However, in vivo experiments demonstrated that Pro@MON@PTA exhibited superior control efficacy compared to prochloraz EW. These findings suggested that MON@PTA holds significant potential for plant disease management.