title: Coupling a microchip with electrospray ionization quadrupole time-of-flight mass spectrometer for peptide separation and identification.
abstract: The present study reports a simple method of coupling a glass microchip to an electrospray ionization (ESI) quadrupole time-of-flight mass spectrometer (QTOF-MS) for separation and identification of peptides. A sheath-flow electrospray interface was constructed based on attaching a short fused-silica capillary to the microchip. The dead volume at the interface was effectively reduced by wet etching an approximate flat-bottom capillary insertion channel coaxial to the end of separation microchannel and using a wire-controlled epoxy-blocking attachment method. The makeup liquid and neb gas were coaxially pumped through two stainless-steel tees to maintain a stable and efficient electrospray. The coupled microchip/ESI-QTOF-MS system was successfully used to carry out electrophoresis separation of peptides and ESI-QTOF-MS identification.
authors.affiliation: Department of Chemistry, Tsinghua University, Beijing, P. R. China.
authors.forename: Hai-Fang
authors.initials: HF
authors.lastname: Li
authors.forename: Jiangjiang
authors.initials: J
authors.lastname: Liu
authors.forename: Zongwei
authors.initials: Z
authors.lastname: Cai
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Lin
mesh_terms: D046209:Electrophoresis, Microchip / Q000295:instrumentation / Q000379:methods*; D005898:Glass; D010455:Peptides / Q000032:analysis* / Q000302:isolation & purification; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D010455:Peptides