Liquid Chromatography Mass Spectrometry (LC-MS) shares a strong link with the HPLC systems above. The LC-MS features improved pumps and injection systems enabling better accuracy and lower background .
The main difference between LC-MS and HPLC is the detection system; whereas HPLC-DAD uses absorption of visible and invisible light, the MS allows greater selectivity by basing its detection on the mass to charge ratio of the compound under investigation.Using a combination of radiofrequency mass filtering, only the ion of interest is allowed to reach the detector.This selectivity enables low level (part per billion, ppb) detection for a number of polar compounds that elsewise could not be detected.
- Phenyl urea herbicides
- Triazine herbicides
- Sulfonylurea herbicides
- Carbamate and N-methyl carbamate pesticides
- PFOS and its derivatives
- Alkyl thioureas (low level)
- Phthalic acids
- Sulphonamide antibiotics
- Malachite/leucomalachite green