Optimisation of ion trap parameters for the quantification of chlormequat by liquid chromatography/mass spectrometry and the application in the analysis of pear extracts

Optimisation of the activation parameters for ion trap mass spectrometric analysis of the chlormequat cation using simplex optimisation enabled the product ion (m/z 58) response to be improved 1000-fold. A comparison of the sensitivity of the optimised ion trap mass spectrometer with that of a triple quadrupole mass spectrometer for liquid chromatography/tandem mass spectrometry (LC/MS/MS) showed that similar limits of detection (LODs) could be achieved. For the MS/MS transition of the (35)Cl precursor to the most abundant product, LODs were 0.8 ng cation mL(-1) (0.004 mg cation kg(-1) pear equivalent) and 1.0 ng cation mL(-1) (0.005 mg cation kg(-1) pear equivalent) on the triple quadrupole and ion trap instrument, respectively.