Efficient and high-quality patterning of biological reagents for surface-based biological assays remains a key challenge in the life sciences. The Microfluidic Probe relies on hydrodynamically confined nanoliter volumes of reagents to interact with the substrate at the micrometer-length scale. By leveraging convective flows, recirculation, and mixing of a processing liquid, the MFP overcomes limitations of existing biopatterning approaches, such as passive diffusion of analytes, uncontrolled wetting, and drying artifacts.

Deposition of biomolecules using the MFP allows high pattern quality, conservative usage of reagents, micrometer precision of localization and convection-enhanced fast deposition. Such a device and method may facilitate quantitative biological assays and spur the development of the next generation of protein microarrays.

Multispot deposition of goat anti-IgG using recirculation with the MFP. Photograph of 130 spots deposited with 1 μL of solution.

Deposition efficiency using the MFP with different concentration of reagents. Ratio of deposited analytes with the MFP compared with pipet-based deposition for concentrations of 5, 20, 35, and 50 μg/mL.