title: Electro-kinetic assisted electrospray ionization for enhanced complex sample analysis.
abstract: In this work, an electro-kinetic assisted electrospray ionization (EK-ESI) source is proposed and characterized. In EK-ESI, an additional auxiliary electric field is introduced in the liquid flow of a nano-ESI. While traveling forward in the electrospray flow, charged analytes also experience a reverse electric field, which pushes them backwards. As a result, analytes could be separated preliminarily based on their electrophoretic mobility during the electrospray process. Experiments show that EK-ESI can reduce charge competition effects in the ESI source and increase biomolecule detection sensitivities. It was also found that EK-ESI effectively ionizes proteins in a relatively mild solvent condition, which does not require the addition of acids or salt buffers into the solvent. As a proof-of-concept study, a very rough separation effect was observed in this study, further experiments and theoretical study will be carried out to enhance its performances.
authors.affiliation: School of Life Science, Beijing Institute of Technology, Haidian, Beijing 100081, China.
authors.forename: Zezhen
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: School of Life Science, Beijing Institute of Technology, Haidian, Beijing 100081, China.
authors.forename: Muyi
authors.initials: M
authors.lastname: He
authors.affiliation: School of Chemical Biology and Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, China.
authors.forename: Lingyan
authors.initials: L
authors.lastname: Liu
authors.affiliation: National Institute of Metrology, Beijing 100013, China.
authors.forename: Xingchuang
authors.initials: X
authors.lastname: Xiong
authors.affiliation: National Institute of Metrology, Beijing 100013, China. Electronic address: fangxiang@china.com.
authors.forename: Xiang
authors.initials: X
authors.lastname: Fang
authors.affiliation: School of Life Science, Beijing Institute of Technology, Haidian, Beijing 100081, China. Electronic address: weixu@bit.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
keywords: Charge competition effects; Electro-kinetic assisted electrospray ionization (EK-ESI); Electrophoresis; Nano-ESI