Redox- and Enzyme-Responsive Macrospheres Gatekept by Polysaccharides for Controlled Release of Agrochemicals

Abstract

Stimuli-responsive materials afford researchers an opportunity to synthesize controlled-release carriers with various potential applications, especially for reducing the abuse of chemical reagents in farmland soil. To enhance the efficiency of agrochemical utilization, redox- and enzyme-responsive macrospheres were prepared by self-assembling β-cyclodextrin-modified zeolite and ferrocenecarboxylic acid (FcA)-grafted carboxymethyl cellulose (CMC). Scanning electron microscopy and Brunauer–Emmett–Teller analysis revealed that pores of zeolite were sealed by the surface coupling of FcA-modified CMC via the formation of an inclusion complex. Salicylic acid (SA) was loaded as a model agrochemical. The release of SA from macrospheres could be triggered in the presence of hydrogen peroxide (oxidant) and cellulase (enzyme); and the corresponding release percentages, 85.2 and 80.4%, were much higher than those of the control sample without responsive groups in water (12.6%) after 12 h. A release kinetic study showed that cellulase could promote carrier dissolution more effectively than the oxidant. The results demonstrate that the dual-responsive macrospheres are promising as a smart and effective carrier for the controlled release of agrochemicals.

Pest Invasion-Responsive Hollow Mesoporous Silica-Linked Carboxymethyl Starch Nanoparticles for Smart Abamectin Delivery

“…All of these formulations have a high loading capacity and sustainable release behavior, but none of them allow the pesticide applicator to regulate when and where the pesticide is released. On the other hand, there are many new controlled release formulations (CRFs) that focus on the on-demand pesticide release with specific release triggers such as pH, , light, redox potential, and enzymes − as a cargo release liberator.…”

Recent advances in the design of controlled- and sustained-release micro/nanocarriers of pesticide

“…42 Thus, the controlled release of AIs can be achieved by combining environmental changes and biological stimulation with drug release. In recent years, researchers have designed controlled-release carriers that release pesticides under different stimuli such as light, 43 temperature, 44 pH, 45 enzymes, 46 redox 47 and ions. 48 The pesticides released by the stimuli-responsive controlled technology have great potential to tackle the defects of conventional procedures, and the stability of pesticides properties can be significantly improved.…”

“…48 The pesticides released by the stimuli-responsive controlled technology have great potential to tackle the defects of conventional procedures, and the stability of pesticides properties can be significantly improved. 47 For the management of harmful organisms, controlled- and sustained-release micro/nanocarriers based on stimuli-responsive characteristics provide greater utilization efficiency and reduce the applied amount of pesticides. 16…”

Biomaterials Technology for AgroFood Resilience

“…For example, Hou et al designed macrospheres loaded with salicylic acid, whose release could be triggered in the presence of hydrogen peroxide (oxidant) and cellulase (enzyme). [192] A novel pH and redox dual-responsive cellulose-based nanogel was also reported. [193] Yang et al constructed a smart plant hormone delivery system for gibberellic acid based on metalorganic frameworks (MOFs) and supramolecular nanovalves that exhibited multistimuli-responsive release under external stimuli including pH, temperature, and competitive agent spermine.…”

“…designed macrospheres loaded with salicylic acid, whose release could be triggered in the presence of hydrogen peroxide (oxidant) and cellulase (enzyme). [ 192 ] A novel pH and redox dual‐responsive cellulose‐based nanogel was also reported. [ 193 ] Yang et al.…”