Thermal analysis of loop mediated isothermal DNA amplification (LAMP) based point-of-care diagnostic device

Highlights: • Effective temperature input must be provided for initiating LAMP reaction at 67 °C. • CFD simulation is efficient in optimizing thermal parameters prior to experiment. • Clearance among walls have profound effect on heat distribution in porous membrane. • Discrete heating reduces overall power consumption compared to isothermal heating. • Case 5-Δx > Δy heating strategy demonstrates minimal device operational time. Loop-Mediated Isothermal Amplification reaction or LAMP has been identified as a feasible DNA amplification process. Paper-based LAMP diagnostic devices offer several advantages for point-of-care (POC) applications. LAMP occurs at a constant temperature of higher limits, which remains a major challenge on-site. This calls for an efficient thermal design which is beneficial in maintaining a constant high temperature at POC locations. The present study reports thermal design and energy consumption analysis of a paper-based LAMP POC device for the first time using CFD analysis. The POC design consists of a rectangular porous membrane embedded on a rectangular solid material, heated from the side walls. Isothermal and discrete heating with different horizontal and vertical clearance configurations are used as a design parameter. CFD analysis of different thermal configurations is carried out in COMSOL Multiphysics platform to solve the energy and convection–diffusion-reaction equation in porous media. The thermal analysis demonstrated that two discrete heating configurations with high horizontal clearance are effective in reducing energy consumption. It was inferred that two portable AA batteries are sufficient for the POC device operation. Overall, the current work successfully demonstrates the energy optimization and speed of operation of the POC medical device by detailed thermal analysis.