Selective Protein Immobilization via DNA Conjugation under Microfluidic Laminar Flow

The feasibility of controlled protein immobilization via DNA conjugation by utilizing laminar flow in a microfluidic device was demonstrated. The glass surface in a microchannel was treated by oligonucleotides. The laminar flow brought different protein-DNA conjugates parallel into the microchannel. DNA recognition allows proteins to be delivered to the desired location. The total internal reflection fluorescence was also applied to monitor the process. Both the specificity and sensitivity were high, and the immobilization and removal of the proteins were repeatable. It was shown that with parallel detection of specific and non-specific recognitions, the accuracy of bio-assay would be effectively enhanced. This strategy could improve the performing quality of biosensors in microfluidic devices.