3D Printed Plant Microneedle Biosensor for Crop Monitoring

Agriculture and agribusiness sectors face a growing gap between the need for early crop stress detection and the limitations of current diagnostic tools for managing yield losses caused by fungal infection and water shortage. Existing laboratory-based assays provide accurate biochemical information but are too slow, expensive, and impractical for field deployment, remote sensing tools lack molecular detail needed for precise decision making. Emerging plant sensor technologies promise continuous monitoring of plant internal chemistry, yet they remain commercially unviable due to high fabrication costs, dependence on specialized manufacturing, and poor durability when exposed to plant fluids. Direct contact sensors often degrade through electrode wear, fouling, and mechanical mismatch, leading to short operational lifetimes and frequent replacement costs that limit scalability for farmers. As a result, growers and agritech companies lack reliable scalable platforms that can deliver actionable plant health insights before visible symptoms appear, preventing timely intervention and reducing return on investment for precision agriculture systems.

Our platform delivers a field-ready, wearable biosensor that lets growers monitor crop stress continuously without destroying the plant. A stereolithography printed resin body houses a three-electrode cell and a 3D printed microneedle array that draws sap through a microfluidic channel into an isolated sensing chamber, protecting the electrodes from abrasion and fouling. The working electrode is coated with a porous reduced graphene oxide chitosan nanocomposite that serves as a universal transducer and can be quickly functionalized with enzymes such as glucose oxidase or horseradish peroxidase to target specific markers like glucose, hydrogen peroxide or oxalic acid. A compact potentiostat and wireless microcontroller transmit real-time data to a smartphone or farm management system, enabling early intervention before visual symptoms appear. Because the device is fabricated without photolithography, manufacturing costs are low, scale-up is straightforward, and the modular design allows rapid customization for new analytes, opening revenue streams in precision agriculture, smart irrigation and plant health diagnostics while reducing labor and pesticide use.