High-performance liquid chromatography-time-of-flight mass spectrometry and its application to peptide analyses.

High-performance liquid chromatography (HPLC) has been successfully interfaced on-line with liquid secondary-ion time-of-flight mass spectrometry, utilizing a continuous-flow interface. Time-of-flight mass spectrometry (TOF-MS) is a low-resolution, high-mass-range technique, compatible with extremely rapid data acquisition rates. Thus a TOF-MS system is extremely well suited for coupling with HPLC. This paper describes the interface used to couple the HPLC and TOF-MS as well as the basic operating principles of such a system. Using both standard and packed-capillary reversed-phase HPLC columns, the HPLC-TOF-MS system has been successfully used to separate and detect peptides, providing molecular weight information for the peptide analytes. Experimental data, including chromatograms (UV, reconstructed ion and selected ion) and mass spectra, are presented to demonstrate the ability of the HPLC-liquid secondary-ion TOF-MS system to resolve chromatographically analytes as well as to resolve mass spectrometrically analytes which are unresolved on the chromatographic column.