A versatile polyphenol-coordinated eco-friendly hollow ZIF-based nanohybrid for precise fungicide delivery and highly efficient suppression of Botrytis cinerea

Considerable attention has been focused on the development of smart and environmentally friendly nano-pesticides that can respond to environmental stimuli, to enhance pesticide utilization while mitigating environmental risks. In this study, boscalid (Bos), a potent fungicide, was loaded into hollow zeolitic imidazolate framework-8 nanoparticles (HZNs) and coordinated with tannic acid (TA) to fabricate a pH-responsive nanohybrid platform (Bos@HZNs@TA). Results demonstrated that the HZNs@TA carriers possessed a distinct rhombic dodecahedral morphology and enhanced hydrophilic properties. The loading capacity of Bos in HZNs@TA was approximately 38.43%. Bos@HZNs@TA exhibited excellent adhesion to tomato leaves and washout resistance. Notably, the release amount of Bos from Bos@HZNs@TA at pH = 5.5 reached 84.6%, which was higher than that at neutral pH conditions for 72 h. The pH-responsive release characteristics of Bos@HZNs@TA was advantageous for its response to the acidic microenvironment created by Botrytis cinerea (B. cinerea). Additionally, Bos@HZNs@TA demonstrated exceptional effectiveness in controlling B. cinerea, surpassing the commercial Bos suspension concentrate. Importantly, Bos@HZNs@TA had no discernible adverse effects on the three non-target organisms, implying a good biocompatibility. This study provides a smart, eco-friendly, and sustainable approach to control B. cinerea effectively for plant protection.