Infrared-Light-Responsive Controlled-Release Pesticide Using Hollow Carbon Microspheres@Polyethylene Glycol/α-Cyclodextrin Gel

Abstract

Controlled release of pesticides by light regulation is one of the most viable strategies recently developed for the highly efficient utilization of agrochemicals. Herein, we report an infrared-light-responsive pesticide delivery system for the controlled release of imidacloprid (IMI) by preparation of functional hollow carbon microspheres (HCMs). After IMI loading and surface functionalization with polyethylene glycol (PEG) and α-cyclodextrin (α-CD), IMI was sequestered in the pesticide system (denoted as HCMs/IMI/PEG/α-CD) as a result of the formation of a PEG/α-CD gel network. Upon the irradiation of infrared light, HCMs with high photothermal conversion efficiency (42.8%) raised the local temperature effectively, leading to the collapse of the gel network and the release of IMI. In comparison to the amount of pesticide release (29%) under sunlight, it could reach 77% driven by infrared light, which was an intriguing improvement. Consequently, HCMs/IMI/PEG/α-CD under infrared light showed significantly higher pest control efficacy on corn borers by 125% than itself alone. This work provides a promising method to intentionally regulate pesticide release and enhance utilization efficiency.

β-Cyclodextrin-Modified Mesoporous Silica Nanoparticles with Photo-Responsive Gatekeepers for Controlled Release of Hexaconazole

“…Especially from 90 to 120 min, a significant transition appeared in the nano-system, implying that cis-Azo structures were mostly converted to trans-Azo structures under the irradiation of visible light, and the detached β-CD recombined with BMMs/Azo again. As a result, Azo in BMMs/Azo/β-CD Nps exhibited trans-cis reversible photoisomerization, which could be mutually transformed from a trans structure to a cis structure under the alternating irradiation of UV-Vis light, which was consistent with previous reports [22,33]. In addition, BMMs-Azo Nps were repeatedly irradiated many times, and no "fatigue" to light was observed, indicating that the nanomaterial had good reversible light-responsive capability.…”

Hydrogen sulphide alleviates Fusarium Head Blight in wheat seedlings

“…With this in mind, Lee et al (2011) previously reported that the slow-releasing H 2 S donor, GYY4137, exhibited novel anti-cancer effects in vitro and in vivo . Likewise, in the work of Liu et al (2021) , they provided an infrared-light-responsive pesticide delivery system to intentionally regulate imidacloprid release and enhance utilization efficiency. Hence, it would be valuable to develop a delivery system that could be manipulated to achieve sustained release of H 2 S from its donor NaHS.…”

Recent development in functional nanomaterials for sustainable and smart agricultural chemical technologies

“…The surface cover could be enzymatically hydrolyzed by α-amylase in insect intestine and causing chlorantraniliprole released to kill insects. With a similar design, Liu et al [ 51 ] loaded imidacloprid to hollow carbon microspheres (HCMs) which were then capped with polyethylene glycol (PEG) and α-cyclodextrin. Because of the photothermal effect of HCMs, the valve layer could be disrupted when the system was exposed to near infrared light, initiating the release of imidacloprid.…”