DETERMINATION OF CLONAZEPAM IN HAIR AND NAIL USING LIQUID CHROMATOGRAPHY TANDEM MASS SPECTROMETRY (LC-MS/MS)

Clonazepam, (5-(2-Chlorophenyl)-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one), a nitrobenzodiazepine and a scheduled drug, is one of the most highly abused drugs in recent times. A sensitive analytical methodology using Liquid Chromatography tandem Mass Spectrometry (LC-MS/MS) was developed for the determination of clonazepam in human hair and nail samples. The method involves the decontamination of hair and nail using 2 mL each of 0.1% SDS (sodium dodecyl sulfate), water, and methanol, dried followed by incubation in phosphate buffer (pH = 8), extraction with diethyl ether:chloroform (70:30, v/v), separation, and detection using liquid chromatography–tandem mass spectrometry. The method was totally validated with the limit of detection (LOD) of clonazepam estimated as 0.50pg/mg and the limit of quantification (LOQ), 2.0pg/mg of hair and nail. Linearity was observed in the range 2.0 pg/mg to 5000 pg/mg with r2 > 0.9980. The extraction recoveries, intra-day and inter-day precisions, accuracy, and matrix eff...