LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY SYSTEM USING COLUMN-SWITCHING TECHNIQUES

A liquid chromatography-mass spectrometry (LC-MS) system, was developed to overcome the problems imposed by the use of non-volatile mobile phases, such as buffers. The peak of interest was heart-cut from the effluent from the analytical column, passed into sampling loops and adsorbed on a trapping column after dilution with the analytical mobile phase. The buffer constituents were washed out and the compounds of interest were eluted from the trapping column and re-chromatographed with a suitable mobile phase for LC-MS. The potential of this system was explored in the LC-frit-fast atom bombardment-MS determination of tocopherol and riboflavin. The system can provide high sensitivity.