日本質量分析学会 第67回質量分析総合討論会

Abstract

Oral Sessions

Day 3, May 17(Fri.) 15:45-16:05 Room D (202)

Sampling and Ionization Process in Scanning Probe Electrospray Ionization

(1Osaka Univ., 2Shizuoka Univ.)
oYoichi Otsuka1, Bui Kamihoriuchi1, Aya Takeuchi1, Futoshi Iwata2, Takuya Matsumoto1

Tapping-mode scanning probe electrospray ionization (t-SPESI) realizes the ambient sampling and ionization (ASI) with a single capillary probe. In order to improve the ASI efficiency in t-SPESI, the understanding and the control of charged solvent is necessary. We developed the measurement system by which the fast acquisition of multiple mass spectra at a certain sample position in order to understand the time course of ion signals during ASI. The ion signal was increased immediately after the stage movement and it was decreased exponentially with increasing time. This result indicates that the molecules on substrate was extracted and consumed for the electrospray. Next, the time course of the probe displacement and the ion signals during a single sampling and ionization event are simultaneously measured for the understanding of the dynamic change of liquid bridge at the probe apex. It was found that the extension time of liquid bridge until its breakage and the ion detection time after the breakage of liquid bridge are correlated with the surface tension and the viscosity of solvent, respectively. Moreover, the effect of experimental parameters of t-SPESI onto the ASI efficiency will be discussed.