Each year, millions of tons of pesticides are used to protect crops. However, traditional formulations release too quickly, degrade easily, and leach away, resulting in low efficiency and environmental risks. Creating smart, controlled-release formulations from existing ingredients is a simpler and more effective way to improve efficiency and reduce ecological harm than the costly and time-consuming development of new pesticides.

A research team led by Profs. WU Zhengyan and ZHANG Jia from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed a bioinspired Prussian blue/PNIPAM nanohybrid (PAPP) with spatiotemporally decoupled release characteristics. 

The results were published in Journal of Controlled Release.

Inspired by the dual-phase biocontrol strategy of parasitoid wasps, this system integrates an alkaline-triggered burst release mechanism to address acute pest outbreaks and thermo/near-infrared (NIR)-responsive sustained release for long-term seasonal control. In this design, Prussian blue nanoparticles serve as alkaline-degradable cores, while poly(N-isopropylacrylamide) hydrogel gates provide heat- and NIR-responsiveness. The dynamic nature of this architecture enables dual-phase pesticide management, combining rapid and sustained release modes.

PAPP nanopesticides exhibit high drug-loading capacity, strong UV resistance, and improved foliar adhesion, ensuring long-lasting stability under field conditions. Experimental results and simulations confirmed their strong insecticidal activity against Plutella xylostella, while reducing harm to crops and non-target organisms such as zebrafish and pollinators. 

Additionally, degradation of Prussian blue releases Fe ions, which serve as beneficial micronutrients for plants, thereby enhancing ecological value.

This work presents a promising approach toward the development of efficient, environmentally friendly pesticide formulations and greatly contributes to the sustainable advancement of agriculture. 

Schematic illustration of fabrication and mechanism of bioinspired Prussian blue nanopesticides. (Image by TENG Guopeng)