Development of ultrahigh‐performance liquid chromatography/mass spectrometry and ultrahigh‐performance supercritical fluid chromatography/mass spectrometry assays to determine the concentration of Bitrex™ and sodium saccharin in homemade facemask fit testing solutions

Fast and easily transferable chromatography/mass spectrometry assays were required to detect and quantify the amount of Bitrex™ and sodium saccharin in homemade facemask fit testing solutions. METHODS: Bitrex™ solutions were analysed using reversed‐phase ultrahigh‐performance liquid chromatography coupled with positive ion electrospray ionisation mass spectrometry (UHPLC/ESI‐MS). Separation was achieved using a mobile phase gradient with an Acquity BEH C18‐packed column. Sodium saccharin solutions were analysed using ultrahigh‐performance supercritical fluid chromatography coupled with negative ion electrospray ionisation (UHPSFC/ESI‐MS). Separation was achieved using isocratic elution with an Acquity UPC(2) Torus Diol packed column and a methanol (25 mM ammonium acetate) co‐solvent. RESULTS: The calibration curves obtained using the ratio of the active compound to an internal standard generated linear regression values (R(2)) >0.99. Samples analysed prior to and after an autoclave sterilisation process and bottling gave repeatable measurements within 10% of the expected concentration. CONCLUSIONS: The two assays afford a fast robust and quantitative analytical method for the detection of the active components used to test the efficacy of the homemade facemask testing solutions.