A team of researchers from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences, has developed an innovative green pesticide formulation that could make pest control safer and more effective for both crops and the environment.
“This new colloidal pesticide can be a more environmentally friendly alternative to traditional pesticides,” said Prof. WU Zhengyan and ZHANG Jia, who led the team.
The study was published in ACS Nano.
Traditional pesticides face several problems. They can be difficult to spread evenly on plant leaves, may wash off easily in the rain, or break down quickly in sunlight. Additionally, residual chemicals from pesticide formulations can harm the environment.
In this study, the team created a new kind of pesticide that uses modified carbon dots and calcium carbonate particles as a carrier for abamectin. This new formula enhances adhesion to leaves, resists degradation from sunlight, and releases the active ingredient gradually for sustained effectiveness.
The secret to this new formulation’s success lies in its structure. The carbon dots (LysCDs) combined with calcium carbonate (CaCO3) increase the pesticide’s ability to hold more abamectin—about 1.7 to 2.1 times more than regular formulations. This means the pesticide can be more effective while using less active ingredient. When the pesticide comes into contact with the weakly acidic environment on plant leaves, the calcium carbonate breaks down, releasing the pesticide more quickly and making it easier to track with the fluorescence from the carbon dots. This "controlled release" helps ensure the pesticide stays active for longer, even under harsh conditions like UV light or rain.
In tests on Plutella xylostella (diamondback moth), a common pest, the new formulation showed excellent pest control, both indoors and outdoors. But it’s not just the pests that benefit from this formula—it’s also safer for the environment. Compared to traditional pesticides, the new formulation showed less harm to non-target creatures like zebrafish and earthworms. What's more, after the pesticide releases its active ingredient, the remaining materials break down into harmless substances like calcium ions (Ca2+), carbon dioxide (CO2), and carbon dots, making it much less likely to cause pollution.
This new approach not only offers a more effective means of pest control but also minimizes the risks associated with pesticide use, such as toxicity to non-target organisms and environmental contamination.
Schematic illustration of fabrication and mechanism of colloidal pesticide formulation. (Image by TENG Guopeng)
