Multifunctional Borax Cross-Linked Hydroxypropyl Guar Gum Hydrogels with Crop Nutritional Function as Carriers for Dual-Responsive Acaricide Release
Huiping Chen, Tengjiao Li, Muhammad Bilal, Chong Cao, Pengyue Zhao, Xiaomao Zhou, Yu Lu, Qiliang Huang, Lidong Cao
Abstract
Hydrogels with porous networks have received considerable attention in smart pesticide delivery due to their inherent versatility. In this study, acaricide cyetpyrafen (CPF)-loaded borax (BO) cross-linked hydroxypropyl guar gum (HPG) (CPF@BO- co -HPG, CBG) hydrogels were prepared by cross-linking and pesticide loading simultaneously. The flowable CBG hydrogels with 3D porous network structures had better wetting and spreading ability on Citrus reticulata Blanco leaves and a hydrophobic interface. The nonflowable CBG hydrogels had pH- and temperature-responsive release properties. Meanwhile, the acaricidal efficacy of CBG against Panonychus citri (McGregor) at both 24 and 48 h was significantly higher than those of CPF-loaded BO-free HPG hydrogels. Furthermore, CBG had a nutritional function for cotton growth and environmental safety for zebrafish. This research developed a BO cross-linked HPG hydrogel as a smart pesticide delivery vehicle and crop nutrient replenishment, which can be widely applied in sustainable agriculture.