PCB-Based Wireless Biomicrofluidic Device for Biochemical Detection toward Point-of-Care Applications

This study presents the design, fabrication, and characterization of a microfluidic device using printed circuit board (PCB) technology, laser engraving acrylic channels, and an LC wireless sensing technique. The proposed method enables rapid fabrication and testing of the microfluidic device. A wireless sensing element, consisting of a PCB-coplanar capacitive sensor and a PCB-coplanar inductor was designed and integrated. Microfluidic channels were fabricated using laser engraving on acrylic, then bonded to the PCB substrate with a UV resin layer to form a complete wireless sensing microfluidic device. The performance of the proposed device was then verified by injecting various biochemical solutions, such as NaCI, glucose, and BSA protein, into the microfluidic channel. The capacitive sensor embedded within the acrylic microchannel was connected to a PCB-coplanar inductor, forming a passive wireless LC sensor that exhibits frequency shifts in response to different biochemical solutions and solution concentrations. By analyzing these different frequency shifts biochemical solution and concentration can be determined, demonstrating the device's capability of detecting certain biochemical solutions. With these initial results, the proposed device has a high potential to be applied in point-of-care applications.