Detection of cathinone and mephedrone in plasma by LC-MS/MS using standard addition quantification technique

Abstract

Background: Cathinones better known as bath salts have been listed as illicit drugs since 2011. Few studies have focused on the analytical extraction techniques and the matrix effect affecting their detection and quantification in biological samples. Matrix suppression of the signal of cathinones has been previously observed in urine sample by LC-MS/MS. This study is aimed to use the standard addition method to overcome the plasma matrix effect on the quantification of cathinone and mephedrone by LC-MS/MS. Findings: The results showed the matrix effect for cathinone at lowest tested concentration (10 ng/ml) was significantly reduced from 210.9 to 133.7%, but not for mephedrone (from 196.8 to 191.9%) by using standard addition method. At the higher tested concentrations of samples, the matrix effects were significantly reduced for both cathinone and mephedrone by using standard addition technique. Conclusions: Standard addition quantitative technique can serve as an alternative quantitative method for LC-MS/MS when suitable internal standards are not available.