NSF Phase II Grant Supports Research To Address Herbicide Drift With Eco-Friendly Additive

JOHN LOVETT

FAYETTEVILLE, ARKANSAS

CelluDot LLC, a startup founded by engineering alumni, will be using a nearly $1 million National Science Foundation grant to optimize a nanotechnology product they developed as doctoral students to mitigate herbicide drift, all in collaboration with the Arkansas Agricultural Experiment Station.

Environment, spray application practices and tank mix composition can all cause herbicides to move off-target — or drift — resulting in unintended damage to nearby crops or other vegetation. CelluDot addresses this $3.1 billion industry problem with a nanocellulose-based technology that keeps herbicides at the site of their intended use, according to Joseph Batta-Mpouma, Ph.D., CEO of CelluDot.

Batta-Mpouma said the $959,510 National Science Foundation’s Small Business Innovation Research Phase II grant supports the company’s research to optimize and commercialize its nanocellulose-based formulation called BioGrip™, for herbicide applications. The all-in-one product has three functions: drift-reducing agent, volatility-reducing agent, and a surfactant, Batta-Mpouma said. BioGrip is made from forestry waste, like sawdust, rather than petroleum-based chemicals.

According to the Arkansas State Plant Board, an average of more than 480 drift complaints were filed annually in Arkansas between 2018 and 2022. Nationally, more than 10,500 complaints for dicamba-related herbicide drift alone were received by the United States Environmental Protection Agency between 2017 and 2021, according to Gurshagan Kandhola, Ph.D., chief technology officer of CelluDot.

CelluDot’s product is designed to add weight to the herbicide spray droplets and make them fall more directly on target during field applications. That’s one way it serves as a drift-reducing agent. It is also designed to reduce volatilization of the active ingredient without compromising its efficacy, Kandhola said. Moreover, Batta-Mpouma noted the product provides eco-friendly surfactant benefits to keep the herbicide on the weeds.

Faculty with the experiment station, the research arm of the University of Arkansas System Division of Agriculture, will further test the herbicide additive in field trials to produce unbiased performance data.

Batta-Mpouma, who earned his doctorate in materials science and engineering at the University of Arkansas under Jin-Woo Kim’s supervision, said the patent-pending technology has potential applications to other agricultural uses. Kim is a professor of biological and agricultural engineering for the university’s College of Engineering and the Division of Agriculture.

Growing need

Farmers growing specialty crops, certified organic plants, and crops not genetically modified to resist specific herbicides have incurred financial losses in the hundreds of millions of dollars due to herbicide drift, Batta-Mpouma said. Using EPA estimates, he noted that up to 70 million pounds of herbicides are lost to the environment each year in the United States due to herbicide drift.

Early in the development phase, Batta-Mpouma and Kandhola learned through interviews with key industry stakeholders that an all-in-one, eco-friendly, and affordable product was needed.

In Phase I of development, Batta-Mpouma said CelluDot validated the product's technical aspects, such as its ability to reduce herbicide volatility and particle drift and increase spray droplet surface tension and herbicide efficacy.

Batta-Mpouma was a doctoral candidate in the materials science and engineering program at the University of Arkansas when he discovered nanotechnology’s capabilities to help with the herbicide drift problem. He partnered with Kandhola on the research to develop a formulation with drift-reducing properties. At the time, Kandhola was a fellow doctoral student in the biological and agricultural engineering program with a research focus on biomass processing.

Early experimental work included extensive materials testing in Kim’s Bio/Nano Technology Laboratory at the Institute for Nanoscience and Engineering of the University of Arkansas.

The company was formed in 2019 during the founders’ participation in the graduate New Venture Development courses as part of the Graduate Certificate in Entrepreneurship. The program, led by the University of Arkansas Office of Entrepreneurship and Innovation, pairs graduate students and postdoctoral researchers with master’s in business administration students, and other students who form interdisciplinary teams to work on business ideas and commercialize technologies.

In Phase II, team CelluDot will focus on the field trials with Division of Agriculture researchers to further test the product, complete regulatory approvals, establish commercial relationships with key players in the industry, and scale up production.

Division of Agriculture faculty conducting field studies on BioGrip include Nilda Roma-Burgos, weed physiology and molecular biology professor, and Tommy Butts, associate professor and extension weed scientist.

Roma-Burgos said her research team will conduct follow-up experiments in Phase II under low tunnel shelters to generate data supporting refined recommendations for commercial applications on key weed species in commodity crops. The efficacy of two dicamba formulations with BioGrip will be tested on multiple weed species in the greenhouse and field, Roma-Bugos added.

This summer, her team wrapped up Phase I testing of efficacy studies on Palmer amaranth and tall waterhemp, also known as pigweeds. Earlier tests included the effects of adjuvant concentration and nozzle type on drift and volatility of dicamba formulations. Roma-Burgos tested the product's earliest formulations for volatility drift in greenhouse and field settings using dicamba-sensitive soybean as the test material. She was a scientific advisor in CelluDot's initial efforts to research and determine BioGrip's efficacy in controlling herbicide volatilization and particle drift.

Next steps

Roma-Burgos will coordinate with Butts as he tests the product in spray-chamber and field-scale experiments. His goal is to provide data on droplet size and velocity and generate the necessary information to run EPA drift simulation models required to begin the process of approval for certain tank mixtures. Butts will also conduct a field drift experiment with a commercial sprayer to evaluate the product compared to an industry standard, verifying the drift potential and modeling results from field-collected data.

The Center for Advanced Surface Engineering initially supported research on the adjuvant under a National Science Foundation's Established Program to Stimulate Competitive Research, or EPSCoR, grant. The grant was awarded through the Arkansas EPSCoR program, ASSET III, where Kim served as a leader of the Cellulosic Thrust. Later, the project earned two University of Arkansas Chancellor's Fund grants to continue advancing the technology. ∆

JOHN LOVETT: University of Arkansas