Detector Bias Gating for Improved Detector Response and Calibration in Matrix-assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

✍ Scribed by Vorm, Ole; Roepstorff, Peter

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 543 KB
• Volume: 31
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/(sici)1096-9888(199604)31:4<351::aid-jms300>3.0.co;2-e

✦ Synopsis

Simple circuitry was developed for detector bias grating as an effective and convenient scheme for conserving the charge in detectors used in mass-analysed laser desorption/ionization time-of-flight mass spectrometry. An enhanced detector response by a factor of 3-10 was observed by detector gating compared with the commonly used low-mass deflection. Further, detector gating allowed the acquisition of the low-mass region of the time-of-flight spectrum at reduced sensitivity. Thus the analyte signal and matrix signals could be obtained in the same spectrum with an excellent signal-to-noise ratio and without exceeding the dynamic range of the digitizer. This feature, along with the recently described sample preparation procedure by fast evaporation, yields matrix ion signals that are very well defined and can be used for highly accurate spectrum calibration. Together, these developments open the way to routine mass determinations with errors in the sub-50 ppm range without adding internal standards.