Microfluidic probe with hydrodynamic flow confinement

Abstract

We have developed a microfluidic probe (MFP) that combines the concepts of microfluidics and of scanning probes. The solid walls of a microfluidic conduit are replaced by liquid boundaries - created by hydrodynamic forces - which efficiently confine a microfluidic jet of processing solution dispensed with the MFP. An immersed surface can be processed locally with the microfluidic jet by positioning the MFP above it. Interestingly, large areas and objects can also be processed by scanning the MFP across them. We illustrate the versatility of this concept with several examples including protein microarraying, protein desorption as an example of erasing, surface gradient patterning, and localized staining of cells. Copyright © 2005 by the Transducer Research Foundation, Inc.