Bioinspired Silica Nanoparticles for Enhanced Adhesion and Retention of Biomolecules: A Sustainable and Green Strategy for Disease Management

The growing significance of sustainable agriculture is underscored by the escalating global demand for food and environmental degradation. Continuously adapting plant pathogens presents a significant challenge to sustainable agriculture, leading to substantial global crop losses. <i>Botrytis cinerea</i> is widely distributed and poses a menace to a diverse range of economically important crops. Conventional delivery strategies for active molecules have a low utilization rate, leading to decreased bioavailability, thus reducing the overall efficacy. Utilizing stimulus-responsive carriers for biomolecule delivery into plants enhances efficiency against target pathogens, minimizes risks to nontarget organisms and the environment, and plays a crucial role in increasing active ingredient bioavailability, reducing application frequency. Here, we have prepared a nanobiopesticide composition with foliage-adhesive properties that shows release in pathological conditions, utilizing biocompatible Guar gum/Salicylic acid (GG/SA) as the encapsulating agent on silica nanoparticles (MSNPs) as the carrier, loaded with tannic acid (TA). In comparison to the naked biomolecule, the GG/SA encapsulation improves the deposition of tannic acid, and the contact angle on tomato leaves is decreased by 28°. The enhanced antiwashing efficiency of ^TanMSNP_GG/SA, compared to its naked biomolecule counterparts, can be attributed to low surface tension and van der Waals interactions. Different from free tannic acid, ^TanMSNP_GG/SA exhibited a responsive release in pathological conditions, leading to sustained and steady biomolecule release and prolonged persistence time. Moreover, the control efficacy of ^TanMSNP_GG/SA against <i>B. cinerea</i> was 94%. Also, they showed no cytotoxicity on NIH3T3 cells. This study anticipates improving the adhesion of biomolecules, maximizing the utilization efficiency with stimulus-responsive carriers, thereby addressing a significant application challenge in the field of agriculture, aligning with ecofriendly agricultural practices, presenting an economically viable option for farmers, and ensuring food safety.