Multifunctional Microfluidic Analysis Systems With High-Throughput ESI-MS Detection

With the advancement of microfluidics, various microfluidic systems coupled with electrospray ionization mass spectrometry (ESI-MS) analysis have been developed and successfully applied in researches of proteomics and life science. However, high-throughput analysis using microfluidic systems with ESI-MS detection still presents a challenge. Moreover, droplet-based microfluidic systems also require powerful detectors such as mass spectrometer to provide abundant information, but research on coupling microfluidic droplet system to ESI-MS just started.In Chapter 1, the principle and progress of the microfluidic systems coupled with electrospray ionization mass spectrometry are reviewed. The ESI-MS structure, ion source design principle, functional electrospray chip as well as the progress of droplet-based microfluidic systems with ESI-MS detection are systematically introduced.In Chapter 2, a novel approach for high-throughput flow injection analysis by ESI-MS was developed based on a capillary emitter and slotted-vial array. Driven by electrokinetic forces, the samples and carrier were sequentially introduced into the capillary for MS detection by moving the slotted-vial array. A throughput of 600 samples per hour was obtained. The presented system has advantages of low cost, ease of fabrication, and high reproducibility.In Chapter 3, a novel interfacing method for droplet-array chip and ESI-MS was proposed. On the basis of this method, a multifunctional microfluidic droplet array system with ESI-MS detection was built to achieve droplet generation, multi-step sample pretreatments and MS analysis. The performance of the system was demonstrated in the proteome analysis of myoglobin and cytochrome C in droplets.