Promising Delivery Platform for Smart Pest Control with High Water-Retaining Capacity

Abstract

Hydrogels have been extensively used in agriculture to improve crop yields for their excellent properties. However, they are currently used either as pesticide delivery platforms or water retention agents alone; the combination of these two functions into one agricultural hydrogel formulation has never been reported, which is crucial to promote sustainable development in agriculture. Herein, using poly(β-cyclodextrin) and adamantane-grafted poly(acrylic acid) (PAA–Ada) as the host and guest, respectively, an easy operating, multi-responsive, and safer hydrogel delivery system for insecticides is fabricated by the host–guest interaction between cyclodextrin and adamantane, which can load uniformly dispersed insecticides (fipronil, imidacloprid, and thiamethoxam) up to 60%. Benefiting from the carboxyl and hydroxyl groups on polymer chains, different temperatures (25, 35, and 45 °C) and pH values (5.0, 6.8, and 10.0) change the intermolecular forces within the hydrogel network and then the diffusion of the content, finally resulting in controlled release behaviors. Besides, this platform can rapidly release the insecticides in the presence of amyloglucosidase due to its ring-opening effect on cyclodextrin. Moreover, this platform exhibits high water-retaining capacity toward soil, which can increase the maximum water absorption of nutrient soil and quartz sand by 31.6 and 13.9%, respectively, and slows down the water loss. Compared with commercial formulation, this smart system reduces the acute toxicity to non-target organism earthworms by 52.4% and improves the efficacy against target organism aphids by 47.3%, showing better durability, lower environmental toxicity, and higher efficiency. To our knowledge, this is the first idea that simultaneously adopts the water-retaining capacity and controlled release ability of hydrogels to improve insecticide efficacy. In this regard, this smart hydrogel platform holds great potentials as slow-release granules with water-holding ability for protection against insect pests, providing an alternative platform for the sustainable development in green agriculture.

Temperature-Responsive Cocrystal Engineering for Efficacious Delivery of Poorly Water-Soluble Herbicide

“…The release data were assessed with the zero-order, first-order, Higuchi, and Ritger–Peppas models to evaluate the release mechanism. , The expressions are as follows normalz ero ‐ order model : M t M ∞ = kt + b first ‐ order model : M t M ∞ = 1 − e − kt Higuchi model : M t M ∞ = k t 1 / 2 + b Korsmeyer ‐ Peppas model : M t M ∞ = k t n where M t is the release amount (in mg) at a given time t , M t represents the amount of release (in mg) at an infinite time point, t is the time (min), k is the kinetic constant, and n is the diffusion parameter.…”

“…The release data were assessed with the zero-order, first-order, Higuchi, and Ritger−Peppas models to evaluate the release mechanism. 43,44 The expressions are as follows…”

Research progress of triazole derivatives in the discovery of agricultural chemicals

“…Pests have seriously threatened the safe production of crops, and effective pest management strategies can greatly reduce crop losses [104,105]. The use of highly effective insecticides has always been the most effective way of pest management [106,107], however, repeated use of the same insecticides over a long period of time can lead to the growth of resistance [108][109][110].…”

Green Nanopesticide: pH-Responsive Eco-Friendly Pillar[5]arene-Modified Selenium Nanoparticles for Smart Delivery of Carbendazim to Suppress Sclerotinia Diseases

“…26−28 However, there is no report on applying Se NPs to control plant pathogenic fungi. 29 Supramolecular macrocycles, including cyclodextrin, cucurbiturils, calixarenes, and pillararenes, have been widely used in many fields, such as pesticide determination, 30 controlled release of pesticides, 31,32 reduction of pesticide toxicity, 33 recognition of drug chirality, 34 and biosensors. 35 Pillar[n]arenes have the advantages of p-rich cavities, symmetrical rigid architectures, and good biocompatibility.…”

“…Proper supplementation of selenium can improve human immunity and resist various diseases. − Selenium nanoparticles (Se NPs) also showed an excellent therapeutic effect in Alzheimer’s disease and drug-resistant bacteria. − However, there is no report on applying Se NPs to control plant pathogenic fungi . Supramolecular macrocycles, including cyclodextrin, cucurbiturils, calixarenes, and pillararenes, have been widely used in many fields, such as pesticide determination, controlled release of pesticides, , reduction of pesticide toxicity, recognition of drug chirality, and biosensors . Pillar­[ n ]­arenes have the advantages of p-rich cavities, symmetrical rigid architectures, and good biocompatibility.…”