Analysis of Barbiturates in Urine by LC-MS/MS.

In the method described here, an aliquot of a urine sample is analyzed to detect barbiturates through dilution and ultra-high-performance chromatography-tandem mass spectrometry (UPLC-MS/MS) using deuterated internal standards. This assay detects the presence of nine barbiturate drugs-amobarbital, barbital, butalbital, butabarbital, mephobarbital, secobarbital, pentobarbital, phenobarbital, and thiopental. This protocol describes two LC separation methods-first LC method (2.