Multiplexed operation of a micromachined ultrasonic droplet ejector array
Thomas P Forbes1, F Levent Degertekin, Andrei G Fedorov
1G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
The Review of Scientific Instruments
|November 6, 2007
Summary
A novel dual-sample ultrasonic droplet ejector array enables faster mass spectrometry (MS) analysis by simultaneously ejecting multiple samples and internal standards for accurate quantification.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry Instrumentation
- Microfluidics
Background:
- Mass spectrometry (MS) analysis time is a bottleneck for high-throughput screening.
- Multiplexed ion sources are needed to analyze multiple samples concurrently.
- Synchronized ejection of samples and internal standards is crucial for accurate quantitative MS.
Purpose of the Study:
- To develop a dual-sample ultrasonic droplet ejector array for multiplexed mass spectrometry.
- To enable synchronized sample and internal standard ejection for improved MS analysis.
- To reduce overall MS analysis time for multiple analyte streams.
Main Methods:
- Device fabrication using micromachining techniques.
- Finite-element analysis simulations for device design optimization.
- Experimental characterization of droplet ejection performance at ~1 MHz frequency.
Main Results:
- Demonstrated isolated ejection of ~5 micrometer water droplets from individual domains.
- Achieved reduced acoustical crosstalk between ejection domains via mechanical shaping.
- Proof-of-concept dual-sample device successfully demonstrated multiplexing potential.
Conclusions:
- The developed ultrasonic droplet ejector array is a viable soft-ionization ion source for multiplexed MS.
- This technology can significantly reduce MS analysis time and improve quantitative accuracy.
- The device design shows promise for scaling to multiplexing larger numbers of analytes.
