title: A reliable and simple method for fabricating a poly(dimethylsiloxane) electrospray ionization chip with a corner-integrated emitter.
abstract: Monolithically integrated emitters have been increasingly applied to microfluidic devices that are coupled to mass spectrometers (MS) as electrospray ionization sources (ESI). A new method was developed to fabricate a duplicable structure which integrated the emitter into a poly(dimethylsiloxane) chip corner. Two photoresist layers containing a raised base which guaranteed the precise integration of the electrospray tip emitter and ensured that the cutting out of the tip exerted no influence even during repeated prototyping were used to ease the operation of the process. Highly stable ESI-MS performance was obtained and the results were compared with those of a commercial fused-silica capillary source. Furthermore, chip-to-chip and run-to-run results indicated both reliability and reproducibility during repeated fabrication. These results reveal that the proposed chip can provide an ideal ion source for MS across many applications, especially with the perspective to be widely used in portable MS during on-site analysis.
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. qian.xiang@sz.tsinghua.edu.cn.
authors.forename: Xiang
authors.initials: X
authors.lastname: Qian
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. vincent_2090@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. yu-cl12@mails.tsinghua.edu.cn.
authors.forename: Cilong
authors.initials: C
authors.lastname: Yu
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. yan.chen@siat.ac.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. yu.quan@sz.tsinghua.edu.cn.
authors.forename: Quan
authors.initials: Q
authors.lastname: Yu
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. ni.kai@sz.tsinghua.edu.cn.
authors.forename: Kai
authors.initials: K
authors.lastname: Ni
authors.affiliation: Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China. wang.xiaohao@sz.tsinghua.edu.cn.
authors.forename: Xiaohao
authors.initials: X
authors.lastname: Wang