Drugs were extracted via solid-phase extraction, and concentrations were determined using a previously published high-pressure liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method.



HPLC-MS/MS
Drugs were extracted via solid-phase extraction, and concentrations were determined using a previously published high-pressure liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method.



HPLC-MS/MS