Multiplexed microfluidic blotting of proteins and nucleic acids by parallel, serpentine microchannels

This work develops a high-throughput, high-efficiency and straightforward microfluidic blotting method for analyzing proteins and nucleic acids. Sample solutions containing antibodies (for protein detection) or hybridization probes (for nucleic acid detection) are introduced into the parallel, serpentine microchannels to specifically recognize the immobilized targets on the substrate, achieving the identification of multiple targets in multiple samples simultaneously. The loading control, molecular weight markers, and antigen/antibody titration are designed and integrated into the microfluidic chip, thus allowing for the quantification of proteins and nucleic acids. Importantly, we could easily distinguish the adjacent blotting bands inside parallel microchannels, which may be difficult to achieve in conventional blotting. The small dimensions of microfluidic channels also help to reduce the amount of probing molecules and to accelerate the biochemical reaction. Our microfluidic blotting could bypass the steps of blocking and washing, further reducing the operation time and complexity.