NiCoNC nanoenzyme enhances the performance of insecticides against Solenopsis invicta by inhibiting the gene expression of P450

The annual invasion of Solenopsis invicta (Buren) (Hymenoptera: Formicidae) has caused significant ecological damage. However, the use of a single type of prevention and control agents and improper use methods have resulted in S. invicta developing a tolerance to pesticides. The development of nanoparticles has shown promise in improving insecticide formulations, and increasing insecticidal efficacy. In this study, we obtained carbon nanotube grafted hexagonal star nanoparticles NiCoNC using zeolitic imidazolate framework-67 (ZIF-67) as a carrier through high-temperature pyrolysis and reduction. The CoNi alloy nanoparticles had an average size of 32.43 nm, and elements C, N, O, Co, and Ni were evenly distributed in the carbon skeleton structure. NiCoNC acted as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Ox) activities, catalyzing H2O2 to generate H2O and O2. The combination of NiCoNC with S. invicta tissue fluid showed significant reactive oxygen species (ROS) scavenging ability. While NiCoNC did not show insecticidal activity against S. invicta, it enhanced the insecticidal activity of the insecticide by entering the intestine. To study the synergistic mechanism of NiCoNC and insecticide, SOD activity, ROS content, detoxification metabolic enzyme activity, and verified function by feeding silenced muscle aponeurosis fibromatosis (Maf) with double-strand RNA. The results showed that NiCoNC decreased the expression of CYP4C1, CYP6A14, and CYP9e2 by expressing SOD activity, and inhibiting the Maf pathway, ultimately increasing the sensitivity of S. invicta to insecticides. In summary, our research has led to the development of a novel nano-enzyme that can significantly enhance the efficacy of flonicamid against S. invicta.