- A simple Janus-type membrane-based wicking microfluidic device fabricated on a polycaprolactone-filled glass microfiber membrane enables separation and collection of blood plasma or serum from whole blood. This device bridges the wicking and cut-capillary-based solution transport mechanisms in a single membrane. The initial portion of the device is fabricated using selective oxygen radical exposure, a technique that enables accurate and precise construction of wicking channel geometries and their combinations. As the fresh blood continues to clot on the device, a separate fraction that is composed almost entirely of serum flows from the sample introduction zone down the channel. The other half of the device is fabricated with microscale capillaries cut into the hard-plastic portion of the membrane to guide and gather fluid into a collection zone. This facilitates blood plasma separation and collection in a single membrane at micro-scale sample and reagent volumes and at minimum cost. This device can be integrated with many diagnostic assays to develop inexpensive point-of-care diagnostic devices. It can also be used as a sample preparation tool to separate blood plasma or serum to aid with sample analysis performed outside of the device.
- Key Words: blood separation, sample preparation, point of care diagnostics, plasma, serum, glass microfiber, polycaprolactone