Tag Archives: Ivonne González-Gamboa

Nano-enabled precision delivery methods for agriculture

A July 23, 2024 news item on Nanowerk provides an introduction to nanoparticles and their potential use in agriculture, Note: Links have been removed,

Nanoparticles could potentially help address agricultural and environmental sustainability issues on a global scale.

Those issues include rising food demand, increasing greenhouse gas emissions generated by agricultural activities, climbing costs of agrochemicals, reducing crop yields induced by climate change, and degrading soil quality. A class of nanoscale particles called “nanocarriers” could make crop agriculture more sustainable and resilient to climate change, according to a group of specialists that includes Kurt Ristroph, assistant professor of agricultural and biological engineering at Purdue University.

“Saying ‘nanoparticle’ means different things to different people,” Ristroph said. In nanodrug delivery, a nanoparticle usually ranges in size from 60 to 100 nanometers and is made of lipids or polymers. “In the environmental world, a nanoparticle usually means a 3- to 5-nanometer metal oxide colloid. Those are not the same thing, but people use ‘nanoparticle’ for both.”

Ristroph helped organize a 2022 interdisciplinary workshop on nanomethods for drug delivery in plants. Funded by the National Science Foundation and the U.S. Department of Agriculture, the workshop was attended by 30 participants from academia, industry and government laboratories.

Many of the workshop participants, including Ristroph, have now published their conclusions in Nature Nanotechnology (“Towards realizing nano-enabled precision delivery in plants”). Their article reviews the possibility nanocarriers could make crop agriculture more sustainable and resilient to climate change.

A July 23, 2024 Purdue University news release (also on EurekAlert but published July 19, 2024) by Steve Koppes, which originated the news item, delves further into the topic of how agriculture could be made more sustainable with nanotechnology-enabled delivery methods, Note: Links have been removed,

“Nano-enabled precision delivery of active agents in plants will transform agriculture, but there are critical technical challenges that we must first overcome to realize the full range of its benefits,” said the article’s co-lead author Greg Lowry, the Walter J. Blenko, Sr. Professor of Civil and Environmental Engineering at Carnegie Mellon University. “I’m optimistic about the future of plant nanobiotechnology approaches and the beneficial impacts it will have on our ability to sustainably produce food.”

Plant cells and human cells have major physiological differences. Plant cells have a cell wall while human cells don’t, for example. But certain tools can be transferred from nanomedicine to plant applications.

“People have developed tools for studying the bio-corona formation around nanoparticles in an animal. We could think about bringing some of those tools to bear on nanoparticles in plants,” Ristroph said. 

When nanoparticles are injected into the bloodstream, many components of the blood stick onto the surface of the nanoparticles. The various proteins sticking to a nanoparticle’s surface make it look different.

The task then becomes figuring out what proteins or other molecules will stick to the surface and where the particle will go as a result. A nanoparticle designed to move toward a certain organ may have its destination altered by white blood cells that detect the particle’s surface proteins and send it to a different organ.

“Broadly speaking, that’s the idea of bio-corona formation and trafficking,” Ristroph said. “People in drug delivery nanomedicine have been thinking about and developing tools for studying that kind of thing. Some of those thoughts and some of those tools could be applied to plants.” 

Researchers already have developed many different architectures and chemistries for making nanoscale delivery vehicles for nanomedicine. “Some of the particle types are transferable,” he said. “You can take a nanoparticle that was optimized for movement in humans and put it in a plant, and you’ll probably find that it needs to be redesigned at least somewhat.”

Ristroph focuses on organic (carbon-based) nanocarriers that have a core-shell structure. The core contains a payload, while the shell forms a protective outer layer. Researchers have used many different types of nanomaterial in plants. The most popular materials are metallic nanoparticles because they are somewhat easier to make, handle and track where they go in a plant than organic nanoparticles.

“One of the first questions that you want to figure out is where these nanoparticles go in a plant,” Ristroph said. “It’s a lot easier to detect a metal inside of a plant that’s made of carbon than it is to detect a carbon-based nanoparticle in a plant that’s made of carbon.”

Last March, Ristroph and Purdue PhD student Luiza Stolte Bezerra Lisboa Oliveira published a critical review of the research literature on the Uptake and Translocation of Organic Nanodelivery Vehicles in Plants in Environmental Science and Technology.

“Not a lot is understood about transformations after these things go into a plant, how they’re getting metabolized,” Ristroph said. His team is interested in studying that, along with ways to help ensure that the nanoparticles are delivered to their proper destinations, and in corona formation. Coronas are biomolecular coatings that affect nanoparticle functions. 

The manufacturability of nanocarriers is another interest area that could be transferred to agriculture from nanomedicine.

“I care a lot about manufacturability and making sure that whatever techniques we’re using to make the nanoparticles are scalable and economically feasible,” Ristroph said.

The manufacturability of nanocarriers is another interest area that could be transferred to agriculture from nanomedicine.

“I care a lot about manufacturability and making sure that whatever techniques we’re using to make the nanoparticles are scalable and economically feasible,” Ristroph said.

Here’s a link to and a citation for the paper,

Towards realizing nano-enabled precision delivery in plants by Gregory V. Lowry, Juan Pablo Giraldo, Nicole F. Steinmetz, Astrid Avellan, Gozde S. Demirer, Kurt D. Ristroph, Gerald J. Wang, Christine O. Hendren, Christopher A. Alabi, Adam Caparco, Washington da Silva, Ivonne González-Gamboa, Khara D. Grieger, Su-Ji Jeon, Mariya V. Khodakovskaya, Hagay Kohay, Vivek Kumar, Raja Muthuramalingam, Hanna Poffenbarger, Swadeshmukul Santra, Robert D. Tilton & Jason C. White. Nature Nanotechnology (2024) DOI: https://doi.org/10.1038/s41565-024-01667-5 Published: 06 June 2024

This paper is behind a paywall.

Agricultural pest control with nanoparticles derived from plant viruses

As with many of these ‘nanoparticle solutions’ to a problem, it seems the nanoparticles are the delivery system. A September 21, 2023 news item on ScienceDaily announces the research,

A new form of agricultural pest control could one day take root — one that treats crop infestations deep under the ground in a targeted manner with less pesticide.

Engineers at the University of California San Diego have developed nanoparticles, fashioned from plant viruses, that can deliver pesticide molecules to soil depths that were previously unreachable. This advance could potentially help farmers effectively combat parasitic nematodes that plague the root zones of crops, all while minimizing costs, pesticide use and environmental toxicity.

A September 21, 2023 University of California at San Diego news release (also on EurekAlert) by Liezel Labios, which originated the news item, provides more information about the problems along with a nod to nanomedicine as the inspiration for the proposed solution, Note: Links have been removed,

Controlling infestations caused by root-damaging nematodes has long been a challenge in agriculture. One reason is that the types of pesticides used against nematodes tend to cling to the top layers of soil, making it tough to reach the root level where nematodes wreak havoc. As a result, farmers often resort to applying excessive amounts of pesticide, as well as water to wash pesticides down to the root zone. This can lead to contamination of soil and groundwater.

To find a more sustainable and effective solution, a team led by Nicole Steinmetz, a professor of nanoengineering at the UC San Diego Jacobs School of Engineering and founding director of the Center for Nano-ImmunoEngineering, developed plant virus nanoparticles that can transport pesticide molecules deep into the soil, precisely where they are needed. The work is detailed in a paper published in Nano Letters.

Steinmetz’s team drew inspiration from nanomedicine [emphasis mine], where nanoparticles are being created for targeted drug delivery, and adapted this concept to agriculture. This idea of repurposing and redesigning biological materials for different applications is also a focus area of the UC San Diego Materials Research Science and Engineering Center (MRSEC), of which Steinmetz is a co-lead. 

“We’re developing a precision farming approach where we’re creating nanoparticles for targeted pesticide delivery,” said Steinmetz, who is the study’s senior author. “This technology holds the promise of enhancing treatment effectiveness in the field without the need to increase pesticide dosage.”

The star of this approach is the tobacco mild green mosaic virus, a plant virus that has the ability to move through soil with ease. Researchers modified these virus nanoparticles, rendering them noninfectious to crops by removing their RNA. They then mixed these nanoparticles with pesticide solutions in water and heated them, creating spherical virus-like nanoparticles packed with pesticides through a simple one-pot synthesis.

This one-pot synthesis offers several advantages. First, it is cost-effective, with just a few steps and a straightforward purification process. The result is a more scalable method, paving the way toward a more affordable product for farmers, noted Steinmetz. Second, by simply packaging the pesticide inside the nanoparticles, rather than chemically binding it to the surface, this method preserves the original chemical structure of the pesticide.

“If we had used a traditional synthetic method where we link the pesticide molecules to the nanoparticles, we would have essentially created a new compound, which will need to go through a whole new registration and regulatory approval process,” said study first author Adam Caparco, a postdoctoral researcher in Steinmetz’s lab. “But since we’re just encapsulating the pesticide within the nanoparticles, we’re not changing the active ingredient, so we won’t need to get new approval for it. That could help expedite the translation of this technology to the market.”

Moreover, the tobacco mild green mosaic virus is already approved by the Environmental Protection Agency (EPA) for use as an herbicide to control an invasive plant called the tropical soda apple. This existing approval could further streamline the path from lab to market.

The researchers conducted experiments in the lab to demonstrate the efficacy of their pesticide-packed nanoparticles. The nanoparticles were watered through columns of soil and successfully transported the pesticides to depths of at least 10 centimeters. The solutions were collected from the bottom of the soil columns and were found to contain the pesticide-packed nanoparticles. When the researchers treated nematodes with these solutions, they eliminated at least half of the population in a petri dish.

While the researchers have not yet tested the nanoparticles on nematodes lurking beneath the soil, they note that this study marks a significant step forward.

“Our technology enables pesticides meant to combat nematodes to be used in the soil,” said Caparco. “These pesticides alone cannot penetrate the soil. But with our nanoparticles, they now have soil mobility, can reach the root level, and potentially kill the nematodes.”

Future research will involve testing the nanoparticles on actual infested plants to assess their effectiveness in real-world agricultural scenarios. Steinmetz’s lab will perform these follow-up studies in collaboration with the U.S. Horticultural Research Laboratory. Her team has also established plans for an industry partnership aimed at advancing the nanoparticles into a commercial product.

Here’s a link to and a citation for the paper,

Delivery of Nematicides Using TMGMV-Derived Spherical Nanoparticles by Adam A. Caparco, Ivonne González-Gamboa, Samuel S. Hays, Jonathan K. Pokorski, and Nicole F. Steinmetz. Nano Lett. 2023, 23, 12, 5785–5793 DOI: https://doi.org/10.1021/acs.nanolett.3c01684 Publication Date:June 16, 2023 Copyright © 2023 American Chemical Society

This paper is behind a paywall.