MEMS ultrasonic ejector array for electrospray mass spectrometry of biomolecules

We developed a novel micromachined ultrasonic electrospray ionization (ESI) microarray which eliminates many limitations of the conventional capillary ESI technology. The proof-of-concept test results are presented and discussed. This technology has potential for operation at low voltages with wide range of solvents, capable of minimizing the required sample size and improving sample utilization, and is inherently suitable for parallel, high throughput mass spectrometric analysis of proteins mixtures of biological significance with multiplexing in the array format. Further, the ultrasonic ESI microarray can be made inexpensive to be disposable owing to its batch microfabrication using a simple process with only steps.