Development of microfluidic droplet shooter for ultrahigh-sensitive mass spectrometry

Here we proposed and developed a microfluidic device to continuously shoot pL droplets toward controlled direction at kHz, and verified a novel sample injection interface with mass spectrometry (MS). Utilizing microscale laminar gas flows of 10 m/s enabled formation and shooting of uniform droplets and accurate trajectory control. On the contrary to a few percent sample injection rate by conventional electrospray ionization (ESI), the proposed microdroplet shooter can achieve 100% injection for ultrahigh sensitive MS detection. This study will open a new horizon for separation analysis, especially proteins and peptides which are important in state-of-the-art biological researches and medical diagnosis.