Improving the Current Stability through the Bubbles-Free Microfluidic Electro-Spray Ionizing Chip

Abstract:

The bubbles in the microfluidic based electro-spray ionizing chips seriously affect the performance of the system. This paper presents a bubble capture method to stabilize the current of the microfluidic based electro-spray ionizing sources. A bubble capture structure was introduced to collect the bubbles. A normal close clamp valve assured a suitable pressure in the bubble capture structure that no liquid in the microfluidic channel can enter; when the bubble capture structure was filled with gas bubbles, the clamp valve was opened to release the bubble and balance the pressure. The results indicated that the current fluctuation, which reflects the stability of the electro-spray ionizing devices, was below 1.8% during the stable cone-jet electro-spray stage (2000V~4500V) for the proposed system, which was a notable improvement comparing with normal microfluidic-based electro-spray ionizing chip without the bubble capture structure.

• Periodical: Key Engineering Materials (Volumes 609-610)
• Pages: 637-641
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.609-610.637
• Online since: April 2014
• Authors: Xiang Qian*, Lang Liu, Quan Yu, Gang Jing, Xiao Hao Wang
• Keywords: Bubbles-Free, Electro-Spray Ionizing, Micro-Fluidics

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