Rapid prototyping of microfluidic probes for biomedical applications

The microfluidic probe (MFP) is an open space microfluidic device that combines the concepts of hydrodynamic flow confinement (HFC) and scanning probes to overcome the closed channel restrictions of conventional microfluidic devices. In biology, this allows for analysis of mammalian cells, neurons and tissue samples that are otherwise difficult to culture in conventional microfluidic devices. In this paper, we demonstrate how 3-D printing can be used to expedite the design-test cycle of the MFP and hence democratize the concept. The 3D printing procedures were adapted in fabricating the MFPs that were used for all experiments. Characterization of MFP's flow profile footprints are performed by comparisons with numerically calculated profiles. Application of the MFP is then used to selectively label adherent cells cultured in a Petri dish, within their conventional culture environment. Results show that while the 3D printed probes contain some artifacts, they function just as well as MFPs microfabricated using conventional techniques. Overall, this fabrication demonstrates a rapid, easy, and affordable fabrication technique for the MFP.