Automated online solid phase extraction ultra high performance liquid chromatography method coupled with tandem mass spectrometry for determination of forty-two therapeutic drugs and drugs of abuse in human urine.

The study deals with a fast (analysis times of around 11 min) simultaneous identification and quantification in human urine of 42 drugs (21 therapeutic and 21 of abuse), through an automated online solid phase extraction ultra high performance liquid chromatography method coupled with tandem mass spectrometry (SPE UHPLC-MS/MS). In the method validation, particular attention was devoted to the matrix effect, through matrix-matched calibration in blank urine, suitably diluted. For all the abuse drugs investigated, the limit of quantitation (LOQ) values are lower than the legal threshold concentration levels, making the method suitable for routine control. The whole procedure was applied in the analysis of urine of patients positive to the I level screening test.