Development and validation of an LC-MS/MS method for the simultaneous analysis of 28 specific narcotic adulterants used in dietary supplements

The purpose of this study was to develop a method to analyse the concentration of multiple illegal narcotics present in dietary supplements. To this end, we established and optimised a procedure using LC-MS/MS simultaneously to analyse 28 narcotic compounds in various forms of dietary supplements, including powders, tablets, liquids and capsules. In addition, candy and cookies that have also had detected cases of adulteration were also analysed. The specificity, linearity, accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), stability and recovery for these methods were validated accordingly. The LOD and LOQ of the LC-MS/MS ranged from 0.01–50.0 to 0.03–100 ng g−1, respectively. The linearity of these results was good (r2 > 0.99), with intra- and inter-day precision values of 0.2–5.2% and 0.2–4.8%, respectively. Further, the intra- and inter-day accuracies of this method were 97.0–103.4% and 94.6–103.1%, respectively. The stability RSD was less than 7.8%. The mean recovery for this ...