Key Takeaways
- Researchers at the National University of Singapore (NUS) have developed dissolving microneedle patches that deliver living biofertiliser directly into plant tissue.
- Greenhouse trials showed faster growth in Choy Sum and Kale while using more than 15% less biofertiliser compared with soil application.
- The approach enables precise dosing, reduces waste, and limits exposure to variable soil conditions.
- The technology shows potential for urban and vertical farming and for high-value crops requiring controlled inputs.
- Findings from National University of Singapore's researchers were published in Advanced Functional Materials in September 2025.
National University of Singapore Introduces Microneedle Biofertiliser Concept
Researchers at the National University of Singapore have developed a new method for delivering biofertilisers using dissolving microneedle patches applied directly to plant leaves or stems. Unlike conventional soil inoculation, the approach places beneficial microbes inside plant tissue, bypassing soil-related constraints such as microbial competition and unfavorable pH conditions.
In greenhouse tests, vegetables treated with the microneedle patches demonstrated improved shoot biomass, leaf area, and height while requiring significantly less biofertiliser than traditional methods. The findings suggest potential efficiency gains and reduced environmental losses associated with fertiliser use.
How the Microneedle Biofertiliser System Works
Gentle and Controlled Delivery
The research team fabricated plant-specific microneedles using polyvinyl alcohol (PVA), a biodegradable and low-cost polymer. The patches carry microscopic needle arrays tailored to leaf or stem thickness. Once pressed into plant tissue using a handheld or 3D-printed applicator, the needles dissolve within approximately one minute, releasing beneficial bacteria or fungi.
Laboratory tests showed minimal plant stress, stable chlorophyll levels, and no lasting tissue damage. Microbial viability remained high for up to four weeks of storage, enabling advance preparation and controlled application.
Improved Nutrient Uptake and Growth Response
Using a cocktail of plant growth-promoting rhizobacteria (PGPR), including Streptomyces and Agromyces-Bacillus, researchers observed stronger growth responses than with soil-based treatments. The microbes migrated from leaves to roots within days, enhancing root microbiome composition and improving nitrogen use efficiency and energy metabolism.
“Our microneedle system successfully delivered biofertiliser into Choy Sum and Kale, enhancing their growth more effectively than traditional methods while using over 15 per cent less biofertiliser,” said Assistant Professor Andy Tay of the National University of Singapore, who led the study.
Potential Applications and Next Steps For National University of Singapore Researchers
The team also demonstrated successful delivery of beneficial fungi, showing improved growth and balanced phytohormone levels. According to the researchers, early applications may include urban and vertical farms where precision dosing is critical, as well as high-value crops such as medicinal plants.
Looking ahead, the researchers plan to explore integration with agricultural robotics and automated systems to support scalability, and to test the technology across a broader range of crops, including strawberries.
Read the entire research on their website.
