posted on 2024-01-10, 20:14authored byWeiyao Yan, Gaohua Hu, Jianhua Xiao, Yulu Liu, Gang Tang, Zhiyuan Zhou, Yuqi Huang, Xiaohong Zhang, Guangyao Yan, Jialu Wang, Yongsong Cao
Photoactivated pesticides (PPs) have photodynamic antimicrobial
activities and show good environmental compatibility and slow resistance
development. However, the disadvantages of easy aggregation, short
duration, and low efficiency seriously restrict the efficient application
of PPs. Hollow mesoporous copper sulfide nanoparticles (HMCuS NPs)
with unique optical properties show photodynamic antimicrobial activity
under light irradiation, which are considered smart drug delivery
carriers due to their good water dispersivity and high drug encapsulation
surface area. Herein, novel acid-responsive photoactivated pesticide
nanocapsules (PPs@HMCuS-CTS NPs) were established by electrostatically
coating HMCuS NPs loaded with PPs (curcumin and physcion) with chitosan
(CTS). The results showed that the obtained nanocapsules had desirable
water dispersivity (PDI0.25) and acid-responsive release properties.
The antimicrobial activity of PPs@HMCuS-CTS NPs under light irradiation
was more than 1.47 times those of PPs alone and the mixture of PPs
and HMCuS NPs due to the synergistic photodynamic antimicrobial activity.
Rainfastness, safety assessment, and genotoxicity evaluation demonstrated
that the PPs@HMCuS-CTS NPs deposited more than 1.28 times PPs on plant
foliage without any damage to the crop. Therefore, acid-responsive
photoactivated pesticide nanocapsules based on HMCuS NPs have the
potential to be an efficient and safe pesticide delivery system.