Scientists have developed a microneedle-based drug delivery technique for plant use, which can deliver precise amounts of agrochemicals to specific plant tissues. The microneedles, which are silk-based, can be used to deliver a calculated payload directly into a plant’s deep tissues, which “will lead to higher efficacy of plant growth and help with disease management,” according to the researchers.

Equipping producers with the means to control the levels of chemical delivery precisely will diminish waste, says SMART.

“Developing delivery systems that efficiently deploy agrochemicals such as micronutrients, pesticides, and antibiotics in crops will help ensure high productivity and high produce quality while minimizing the waste of resources is crucial.”

“The technique saves resources compared to current methods of agrochemical delivery, which suffer from wastage,” says Professor Benedetto Marelli, principal investigator at DiSTAP and associate professor of Civil and Environmental Engineering at MIT.

“During the application, the microneedles break through the tissue barriers and release compounds directly inside the plants, avoiding agrochemical losses,” he continues.

“The technique also allows for precise control of the amounts of the agrochemical used, ensuring high-tech precision agriculture and crop growth to optimize yield.”

Current delivery systems “are inefficient due to off-target application, quick run-off in the rain, and actives’ rapid degradation,” says SMART, noting that “these practices also cause significant detrimental environmental side effects, such as water and soil contamination, biodiversity loss and degraded ecosystems, as well as public health concerns, such as respiratory problems, chemical exposure and food contamination.”

In contrast, the silk microneedle technique is “minimally invasive” and delivers its payload without causing any long-term damage to the plant. 

As such, SMART says it “minimizes resource wastage and mitigates the adverse side effects caused by agrochemical contamination of the environment.”

The technology was developed by researchers from the Disruptive & Sustainable Technologies for Agricultural Precision (DiSTAP) Interdisciplinary Research Group (IRG) of the Singapore-MIT Alliance for Research and Technology (SMART), MIT’s research enterprise in Singapore and collaborators from both Temasek Life Sciences Laboratory (TLL) and Massachusetts Institute of Technology (MIT).

Future applications
The developers of the technology have high hopes for its potential usage.

“In the future, with automated microneedle application as a possibility, the technique may be used in high-tech outdoor and indoor farms for precise agrochemical delivery and disease management,” says Dr. Yunteng Cao, postdoctoral associate of Civil and Environmental Engineering at MIT. 

For the researchers, scaling this technology is the next step.

“Our research has validated the use of silk-based microneedles for agrochemical application, and we look forward to further developing the technique and microneedle design into a scalable model for manufacturing and commercialization,” says Professor Daisuke Urano, TLL principal investigator and NUS adjunct assistant professor.