Development of an Affordable Fabrication Platform for Lateral Flow Assays using 3D Printed Devices

Lateral flow assays (LFAs) are among the most widely used point-of-care diagnostic tools due to their simplicity, rapid readout, and low cost. However, the fabrication process of these assays, particularly the precise dispensing of reagents onto nitrocellulose (NC) membranes, requires specialized instruments that are often prohibitively expensive for small laboratories and educational institutions. Commercial dispensing systems typically cost between USD 10,000 and 20,000, creating a barrier to reproducible LFA research and development in low-resource settings. In this study, an affordable, simple, and 3D-printed dispensing system was designed and developed using Arduino-based electronic control. The device consists of modular 3D-printed components (frame, roller assembly, and adjustable mounts), an Arduino Uno R3, L298N motor driver, dual DC gear motors, a variable resistor (WH148) for speed control, and an I2C 16×2 LCD module for real-time display. The system enables precise speed adjustment and uniform membrane movement during reagent deposition. Fabrication cost was approximately USD 56, significantly lower than commercial alternatives. Experimental evaluation using dyed reagents demonstrated repeatable and uniform line deposition across a range of operating speeds. Line width was inversely proportional to membrane speed, with satisfactory reproducibility for laboratory-scale LFA fabrication. The prototype’s simplicity and modularity make it particularly suitable for academic research, training laboratories, and early-stage assay development. Future enhancements include closed-loop motor control and potential integration of AI-assisted image feedback for automated quality assessment. Overall, this work contributes to the democratization of diagnostic device fabrication by providing a low-cost, accessible alternative to commercial reagent dispensers.