Programmable 3DP microfluidic bio-reaction system: automated LAMP-on-a-chip

Abstract

Point-of-care (PoC) devices have revolutionized healthcare by enabling remote diagnostics and therapeutics, with microfluidic systems playing a pivotal role in their advancement. This study focuses on the detailed engineering and characterization of three-dimensional hydrophobic valves to form novel programmable bio-reaction reservoirs. Using 3D-printed soft lithography, we meticulously investigated the effects of channel dimensions and surface properties on the burst pressures of these reservoirs, which ranged from 6.4 to 44.8 mbar. The bio-reaction reservoirs were demonstrated in both series and parallel configurations, offering versatile platforms for the miniaturization and automation of biological processes. Our findings highlight the capability of these reservoirs to program flows in a variety of fluid samples, including water, blood and serum. Additionally, a portable pressure pump was developed to leverage the functionality of these hydrophobic valves, enabling precise control of fluid dynamics in PoC applications. The study culminated in the design of a microfluidic chip integrating two consecutive reservoirs for the PoC execution of loop-mediated isothermal amplification (LAMP) for detection of the Mpox virus. Primers were lyophilized within the bio-reservoirs, and the system successfully enabled visible colorimetric detection via the LAMP assay.