Multiplexed detection of CRP-SAA1 using laser direct-write-fabricated multiple flow-path lateral flow devices (Conference Presentation)

Abstract

Demand for low-cost alternatives to conventional medical diagnostic tools has been the driving force that has spurred significant developments in the diagnostics field. Lateral flow devices (LFDs) are one of the simplest and most established formats of paper-based devices, and are regarded as ideal point-of-care diagnostic solutions. In recent years, there has been an increasing need for performing multiplexed diagnostics at the point-of-care for rapid and simultaneous detection of different analytes within a single fluidic sample. Here, we report a novel multiplexing strategy – detection of different analytes individually in the multiple paths of a single LFD. These multi-path LFDs were created via the precise partitioning of the single flow-path of a standard LFD using our previously reported laser direct-write (LDW) technique. Unlike other multiplexing methods, our distinctive approach, presented here, creates multiple parallel flow-paths inside a ‘single’ LFD without increasing its original footprint, and hence does not require larger sample volumes, and, most importantly, eliminates the interference between individual detection sites positioned within the same channel as in the case of other multiplexing strategies. We show the use of an LDW-patterned dual-channel LFD as an example for the implementation of multiplexed detection of C-reactive protein (CRP) and Serum amyloid A-1 (SAA1), biomarkers commonly used for the diagnosis of bacterial infections. To further validate our multiplexing strategy, we have also tested our LFDs with clinical samples (blood serum from patients with increased systemic inflammation) and the results show a high consistency with those acquired using the gold-standard, an ELISA test.