A MEMS electrospray nozzle for mass spectroscopy

We present our development of a micron-sized MEMS electrospray nozzle and demonstrate its application for electrospray mass spectroscopy (MS). The fabricated and tested micromachined electrospray nozzles are typically 40 /spl mu/m long and with 1-3 /spl mu/m orifice diameters. They also have built-in particle filters. This micromachined nozzle has been successfully interfaced with a mass spectrometer (Finnigan Mat LCQ Ion Trap) to perform standard characterization using a solution of gramicidin S at a flow rate of 50 nL/min and a voltage potential of 4 kV. This MEMS nozzle has demonstrated valid MS analyses with lower flow rates, and it has many advantages over the traditional complex preparation of a glass-capillary.