Tannic Acid-Modified MXene as a Nanocarrier for the Delivery of beta-Cyfluthrin as a Sustained Release Insecticide

The construction of a smart pesticide delivery system (PDS) is an effective strategy to overcome the low utilization of conventional pesticide formulations. This work reports a beta-cyfluthrin (beta-CYF) PDS using tannic acid (TA)-modified MXene (Ti3C2) as a nanocarrier and investigates its pH-responsive release performance, leaf affinity, insecticidal activity against Culex pipiens pallens, and biosafety to maize and Vigna radiata (Linn.) Wilczek. By self-polymerization of TA on MXene, the MXene-TA nanocarrier was formed, and then beta-CYF was loaded by physical adsorption, with a high loading rate of 44.69%. Different from the burst release of technical beta-CYF, the nanopesticide exhibits pH-responsive controlled release performance, and the acid environment is more conducive to beta-CYF release. In addition, the leaf affinity of the nanopesticide is also improved because of the surface modification of TA. According to the insecticidal experiment, this PDS shows better activity than technical beta-CYF, which can maintain high insecticidal activity even after 28 days. The biosafety results further verify that this PDS has no toxicity to maize and V. radiata (Linn.) Wilczek. We think that MXene-based PDSs will have a brilliant future in pest control and agriculture.