UHPLC-MS/MS Determination of Common Narcotic Drugs in Biological Samples

A method of UHPLC-MS/MS for the determination of 3 common narcotic drugs, i.e., methamphetamine, morphine and 6-acetylmorphine, in blood, urine and saliva was proposed. Protein in sample was precipitated with acetonitrile and the filtrate obtained after centrifugation was analyzed by UHPLC-MS/MS. Linear relationships between values of peak area and mass concentration of the 3 drugs were kept in the ranges of 1-500 μg·L-1 for methamphetamine and 1-1 000 μg·L-1 for morphine and 6-acetylmorphine, with detection limits (3S/N) in the range of 0.2-0.5 μg·L-1. Recovery and precision of the method were tested by addition of mixed standard of the 3 drugs at 3 concentration levels of 10, 20, 50 μg·L-1, giving values of recovery in the range of 62.4%-106.3%. Values of intraday and interday relative standard deviation (n=6) found were in the ranges of 3.4%-17.4% and 6.1%-17.8% respectively.