%0 Journal Article %A Devenport, Neil A. %A Sealey, Laura C. %A Alruways, Faisal H. %A Weston, Daniel J. %A Reynolds, Jim %A Creaser, Colin %D 2013 %T Direct detection of a sulfonate ester genotoxic impurity by atmospheric-pressure thermal desorption−extractive electrospray−mass spectrometry %U https://repository.lboro.ac.uk/articles/journal_contribution/Direct_detection_of_a_sulfonate_ester_genotoxic_impurity_by_atmospheric-pressure_thermal_desorption_extractive_electrospray_mass_spectrometry/9395102 %K untagged %K Chemical Sciences not elsewhere classified %X A direct, ambient ionization method has been developed using atmospheric pressure thermal desorption−extractive electrospray−mass spectrometry (AP/TD-EESI-MS) for the detection of the genotoxic impurity (GTI) methyl p-toluenesulfonate (MTS) in a surrogate pharmaceutical matrix. A custom-made thermal desorption probe was used to the desorb and vaporize MTS from the solid state, by rapid heating to 200 °C then cooling to ambient temperature, with a cycle time of 6 min. The detection of MTS using EESI with a sodium acetate doped solvent to generate the [MTS+Na]+ adduct ion provided a significant sensitivity enhancement relative to the [M+H]+ ion generated using a 0.1% formic acid solvent modifier. The MTS detection limit is over an order of magnitude below the longterm daily threshold of toxicological concern (TTC) of 1.5 μg/g and the potential for quantitative analysis has been determined using starch as a surrogate active pharmaceutical ingredient (API). %I Loughborough University