In Planta Nitrate Sensor Using a Photosensitive Epoxy Bioresin

Area of Science:

• Agricultural Science
• Materials Science
• Electrochemistry

Background:

• Effective nitrogen management is crucial for agricultural productivity and environmental sustainability.
• Current methods for monitoring crop nitrate levels are often costly, labor-intensive, and require specialized expertise.
• Existing plant nitrate sensors have limitations such as short shelf life, high cost, and specific storage requirements.

Purpose of the Study:

• To develop a stable, selective, and cost-effective sensor for monitoring nitrate levels in plants.
• To overcome the limitations of current enzymatic electrochemical sensors for nitrate detection.
• To enable frequent and direct in planta nitrate monitoring in living plants.

Main Methods:

• Fabrication of a novel bioresin (SU8-GO-VB12) incorporating vitamin B12 (VB12) and graphene oxide (GO).
• Patterning the bioresin using photolithography and selective laser pyrolysis to create a carbon-based nanocomposite (C-GO-VB12).
• Development of a microelectromechanical system (MEMS)-based needle sensor utilizing the C-GO-VB12 material for in situ measurements.

Main Results:

• The C-GO-VB12 sensor exhibits synergistic properties from VB12, GO, and pyrolytic carbon for superior nitrate detection.
• The sensor demonstrates a year-long shelf life, high selectivity, and a wide dynamic range for maize stalk sap analysis.
• The MEMS needle sensor allows direct, sample-free in situ monitoring of nitrate dynamics in living maize plants.

Conclusions:

• The developed C-GO-VB12 sensor offers a significant advancement for real-time in planta nitrate monitoring.
• This technology provides a cost-effective and stable alternative to existing nitrate testing methods.
• The needle sensor facilitates a deeper understanding of plant nitrogen dynamics and physiological responses, impacting plant sciences.