Open AccessPulse-Heating Ionization for Protein On-Chip Mass Spectrometry
Author(s) -
Kiyotaka Sugiyama,
Hiroki Harako,
Yoshiaki Ukita,
Tatsuya Shimoda,
Yuzuru Takamura
Publication year - 2014
Publication title -
analytical chemistry
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 2.117
H-Index - 332
eISSN - 1520-6882
pISSN - 0003-2700
DOI - 10.1021/ac501407c
Subject(s) - chemistry , microheater , mass spectrometry , analytical chemistry (journal) , thermal ionization , ionization , ambient ionization , analyte , ion , silicon , chromatography , chemical ionization , electron ionization , medicine , alternative medicine , organic chemistry , pathology , fabrication
An on-chip pulse-heating ionization source for protein samples was developed for the realization of miniaturized mass spectrometry. A protein analyte was ionized on a chip by applying only thermal energy to the solid phase sample without a laser, high voltage, or heated ambient gases. A fabricated ionization source consisting of a Pt/Cr microheater (width: 30 μm; length: 100 μm) on a silicon substrate was coupled with a time-of-flight mass filter to analyze a protein sample of bovine serum albumin (BSA, M = 66 kDa). A singly charged BSA ion and other multiply charged BSA ions were generated in the presence of 2,5-dihydroxybenzoic acid as a matrix. To detect the singly charged BSA ion, the required surface energy density of 1.65 × 10(-2) μJ/μm(2) was applied to the microheater for 500 ns. The use of the 2,5-dihydroxyacetophenone matrix resulted in the generation of the multiply charged protein analyte, while the use of the sinapic acid matrix showed abundant peaks in the low m/z region.