The section makes use of a Thermo Surveyor liquid chromatograph interfaced with a Thermo TSQ Quantum Classic triple quadropole mass spectrometer, facilitating the analysis of polar thermolabile compounds up to molecular weigh 1500. Selected ion monitoring (SIM) on the first quadropole or selected reaction monitoring (SRM) on the third quadropole is used for quantification. The latter is more sensitive and a limit of quantitation of 1fg on column has been obtained for some compounds. The instrument is equipped with both electrospray (ESI) and atmospheric pressure chemical ionisation (APCI) sources and spectra can be generated in both positive and negative modes. Full parent ion scan and selected ion monitoring is performed on the first quadropole, whereas the third quadropole is used for full scan, product ion scans, SRM and neutral loss scanning.