Droplet DNA binding detection on microfluidic flow-focusing

We report the interfacial DNA binding by observing size shift of droplets in a flow-focusing device. Molecular binding at the phospholipid on oil-water interface causes interfacial energy change which alters the droplet production rate in the microchannel. Smaller droplets were produced at the orifice due to a complementary DNA binding compare with non-complementary DNA and control cases. Our report contains flow condition tuning for clear distinction of binding events and molecular protocol to modify the interface with single-strand (ss) DNA.