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Pretilachlor (Pre) is an efficient and broad-spectrum pre-seedling herbicide, however, with excessive use of Pre common formulation, it caused phytotoxicity to rice seedlings (Oryza sativa), toxicity to soil organisms, and...

Background: ω-hexatoxin-Hvn1b is an insecticidal toxin produced by the Tasmanian funnel-web spider (Hadronyche venenata), that can be exploited for development of novel bioinsecticides. Due to its larger size and low membrane permeability, this toxin usually has a slower mode of action compared to conventional small molecule insecticides. Nanoscale materials have unique optical, electrical, mechanical and biological properties, and show great application prospects for pesticide delivery.Results: The physical and chemical properties of nanocapsules were characterized using transmission electron microscopy, laser particle size analysis, Fourier transform infrared spectroscopy, contact angle testing and with a fluorescence spectrophotometer. The results indicated that the nanocapsules were spherical, with an average particle size of 197.70 nm, the encapsulation efficiency rate was 75.82% and the Zeta potential was −32.90 mV. Penetration experiments showed that the nanocapsules could promote protein passage through the intestinal tract of Spodoptera litura and reach the body fluid. Then we expressed ω-hexatoxin-Hvn1b by prokaryotic expression. Bioassay results showed that the oral toxicity of ω-hexatoxin-Hvn1b nanocapsules to S. litura was higher than that of the ω-hexatoxin-Hvn1b. Conclusion:In this paper, we reported a construction method of spider venom peptide nanocapsules based on polylactic-coglycolic acid by multiple emulsion for delivery of protein to improve the insecticidal effect and oral activity of ω-hexatoxin-Hv1a.