Integrated microfluidic probes for cell manipulation and analysis

The microfluidic probe (MFP) is a non-contact technology that applies the concept of hydrodynamic flow confinement within a small gap to eliminate the need for closed conduits, and thus overcomes the conventional microfluidic "closed system" limitations. It is an open-space microfluidic concept, where the fluidic delivery mechanism is physically decoupled from the target surface to be processed such as tissue slices or cell culture in Petri dishes. Typically, MFPs are manufactured using complex photolithography-based microfabrication procedures that limits innovation in MFPs' design and integration. Recently, we showed that 3D printing can be utilized for rapid microfabrication of MFPs, where MFPs can be manufactured with built-in components such as reservoirs, fluidic connectors, and interfaces to the XYZ probe holder. 3D printing brings flexibility in MFP design, where different configurations and aperture arrangements can be considered. Currently, we are developing advanced MFPs that are integrated with other technologies and targeting applications in dielectrophoretic-based cell separation, immuno-based cell capture for isolating circulating tumor cells from blood samples, and efficient and selective single cell electroporation. In this invited paper, we highlight several MFP technologies we are developing.