At Purdue University, researchers are working at the tiniest scale to tackle some of agriculture’s biggest challenges. While their innovations may be microscopic, their impact could transform how the world grows its food.
Unlocking the Power of Nanoparticles in the Field
Tucked away in a quiet upstairs lab, scientists are developing “nanocarriers"— ultra-tiny particles designed to deliver pesticides, fungicides and herbicides more precisely to plants.
“We work with agrochemicals from insecticides to fungicides and [are] even starting to work with herbicides now,” says Caleb Fretz, a Purdue PhD student. “The goal is to try to increase the delivery efficiency of those active ingredients using nano delivery as a way of getting them to their biological targets.”
Currently, less than 0.1% of pesticides actually reach their intended targets. Purdue’s team hopes to boost that to 1% or more — a tenfold leap that could revolutionize efficiency and cut costs for farmers.
“If we can get even 1% of our pesticide to its target, that’s a huge leap in efficiency,” adds Luke Johnson, a fellow PhD student in Agricultural and Biological Engineering.
Assistant professor Kurt Ristroph, who leads related nanotechnology work at Purdue, highlights the broader vision.
“Our team’s focus on nanocarriers could make crop agriculture more sustainable and climate-resilient,” he says.
Precision Targeting: How Nano-Encapsulation Works
These particles, often organic and built with a protective shell, are engineered to shield and deliver their active ingredients exactly where crops need them most. The nano-shells allow them to travel through a plant’s leaf, stem and roots to get closer to the target.
Citrus Greening, a disease currently devastating orange trees in Florida, often takes up residence in the tree’s phloem. That area is traditionally a hard-to-access region where pests and diseases hide.
“We can tune what we put on the surface and the size [of the particle] to better reach those targets,” Johnson says.
They’re also able to engineer surface charges and add biomolecules, like sugars, in order to direct treatments to precise locations inside plants.
“If we can translocate our nanopesticide through the leaf, stem and down to the roots where pests lay eggs, we can dramatically reduce the amount of chemicals needed,” explains fellow researcher Bilal Ahmed.
Tracking these particles is also crucial as the technology prepares to undergo regulatory approval.
“I am developing ways to track these particles using metals, tagging them with different receptors,” Fretz says. “That way, we know exactly where they go — whether to the roots, inside the phloem or elsewhere.”
Collaboration and the Road to Sustainable Agriculture
This research is part of a larger collaboration across academia, industry and government.
Ristroph recently organized a major symposium on nanotechnology for plant drug delivery, with findings published in Nature Nanotechnology.
“The precise delivery enabled by nanotechnology could revolutionize agriculture,” notes Professor Greg Lowry from Carnegie Mellon University, a co-author of the study. “But, there are still technical challenges we must address.”
For Purdue’s team, practical application is just as important as scientific discovery.
“It needs to be something you can load in your sprayer and apply just like current formulations,” Fretz says.
The aim is to make the transition seamless for farmers, enabling quick adoption and scaling.
As agriculture faces rising costs, climate variability, and a need to limit environmental impact, this nano-scale innovation offers hope.
“We want to apply less pesticide, less often —improving farmers’ bottom lines and reducing chemicals in the environment,” Johnson says.
It’s a tiny idea with the potential for a giant leap in global farming — one that could make agriculture more efficient, affordable and sustainable for generations to come.
