A Digital Signal Processing-Assisted Microfluidic PCB for On-Chip Fluorescence Detection

We report the use of digital signal processing (DSP) strategies to realize high-sensitivity on-chip fluorescence detection in microfluidic-opto-electronic printed circuit board (PCB) devices without requiring bulky high-quality optical components and filters. An isotachophoresis (ITP) assay was studied in a microfluidic PCB with an embedded standard complementary metal oxide semiconductor sensor array demonstrating a detection sensitivity of 10-nm initial concentration for fluorescein. The amplified ITP signal is processed with the DSP algorithms allowing the fluorescence signal extracted from noisy sensor output to achieve high signal-to-noise ratio. The DSP-assisted fluorescence detection system utilizes off-the-shelf, consumer-grade electronics and lensless imaging to achieve high-level but also scalable integration on microfluidic PCBs.