Source Chemical Engineering Journal

Published  Sep 2026

DOI: 10.1016/j.cej.2026.182584

IF 12.5

Abstract  Leaf-mining insects represent one of the most recalcitrant groups of agricultural pests, as their larvae develop entirely within leaf mesophyll tissues, where pesticide exposure is severely limited. Here, we reveal that the leaf-mining behavior of the globally invasive insect Tuta absoluta imposes a dual physical barrier to pesticide delivery: first, the intact leaf epidermis acts as a primary diffusion-limiting layer; second, larval frass accumulates at the mine entrance, forming a hydrophobic occlusive plug that further impedes active ingredient penetration. To address this challenge, we engineered a hydrophilic-lipophilic diblock polymer (HLDP)-based nanoscale chlorantraniliprole (CAP) formulation with a pesticide loading capacity of 27.5%, designed to simultaneously enhance interfacial adhesion and trans-epidermal transport. Multi-scale analyses revealed that CAP loading proceeds via hydrogen bond-mediated, enthalpy-driven self-assembly, yielding nanoparticles with a uniform size distribution (144.95 nm) and positive surface charge (25.05 mV). These physicochemical attributes collectively improved foliar performance: contact angle decreased by 14.28%, droplet retention increased by 48.23%, and epidermal penetration efficiency rose 1.17-fold relative to unformulated CAP. Consequently, CAP@HLDP achieved markedly enhanced bioavailability, increasing CAP accumulation in leaf tissues by 2.95-fold, in plant cells by 1.78-fold, and in intracellular trafficking compartments by 1.32-fold. Laboratory and semi-field bioassays confirmed superior insecticidal efficacy against T. absoluta, with the nanoformulation exhibiting an LC₅₀ of 4.61 mg/L, 13.1-fold lower than that of conventional CAP (60.21 mg/L). Overall, this work introduces a behavior-guided nano-delivery paradigm that directly counteracts the protective microenvironment created by leaf-mining activity. By using pest behavior as a biological rationale for nano-delivery optimization, our strategy offers a scalable, mechanism-based framework for managing concealed herbivores and advancing precision, low-dose pest management.