Advances in Medical Diagnostics Using LoC and LoPCB Technologies

Estimated reading time: 14 minutes

Figure 8: The experimental LoPCB biosensing platform; (a) integrated LoPCB stackup; (b) electrochemical impedance spectroscopy electrode configuration; (c) commercially fabricated PCB biosensing platform; (d) sample delivery microfluidics ^[4].

Dr. Moschou’s recent work is shown in Figure 9, which is a three-layer multilayer experiment where the construction is:

• Layer 1: Reference layer plated with copper, silver, and silver chloride (Figure 5b&c)
• Layer 2: Sensing electrodes plated with hard gold
• Layer 3: the microfluidic layers for the sample solution

A 3D exploded view, as well as the plated layers, are also shown. The experimental test board proved very successful, so a full LoPCB substrate was designed (Figure 10). This fully integrated PCB cartridge (4.6 cm x 5.7 cm) includes the microfluidic channels for handling the sample, reference electrodes, and working electrodes. It is designed to measure the biomarkers for the test for tuberculosis. In addition to the three-layer construction, the cartridge contained:

• PCI express electrical interfacing
• Six channels (four standard curve points within the clinical range, one negative control, and one sample)
• 10 µL reaction chambers
• Three amperometric sensors per channel
• Full assay implemented on the PCB