Nano-encapsulation of pyraclostrobin within mesoporous silica mitigates toxicity in zebrafish (Danio rerio)

Pyraclostrobin, a widely used broad-spectrum fungicide, poses significant ecological risks to aquatic ecosystems due to its high toxicity to non-target organisms, limiting its application in paddy fields. To address these challenges, this study developed a nano-controlled release system of pyraclostrobin encapsulated within pectin-coated mesoporous silica nanoparticles (Pyr@MSN-Pec). The novel formulation exhibited sustained-release properties, significantly enhanced antifungal activity against Magnaporthe oryzae (EC 50 = 0.007 mg/L compared to 0.021 mg/L for conventional pyraclostrobin), and substantially reduced acute toxicity to zebrafish (LC 50 increased from 0.046 mg/L to 0.314 mg/L). Furthermore, zebrafish embryos exposed to Pyr@MSN-Pec exhibited lower incidences of developmental abnormalities, impaired autonomous movement, and oxidative stress responses compared with those exposed to free pyraclostrobin. These findings highlight the potential of Pyr@MSN-Pec to enable safer and more effective fungicide applications in rice cultivation, supporting the development of more sustainable pest management strategies.