An efficient and label-free LC-MS/MS method for assessing drug's activity at dopamine and serotonin transporters
Zebin Lin1,2, Chenyang Liu1,2, Enshan Fan1
1Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, China.
Background:
Dopamine transporter (DAT) and serotonin transporter (SERT) are targets for many psychoactive substances. Functional assays including uptake inhibition and release assays often involve radiolabeled compounds like [3H]-dopamine and [3H]-serotonin to assess drug activity at transporters, which have high requirements on handling radioactive samples.
Aims:
The aim of this study was to establish a label-free method to assess drug activity at DAT and SERT.
Methods:
A liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method was established using transporter-transfected human embryonic kidney 293T (HEK293T) cells. This method was evaluated by testing the effects of amphetamine and cocaine in the assay procedure.
Results:
The limits of detection of this method were 0.2 nM for both dopamine (DA) and serotonin (5-HT), with good linearities in the range of 0.5-160 nM. Amphetamine and cocaine's IC50 and EC50 on DAT and SERT determined by this method were consistent with previous reports.
Conclusions:
A rapid, reliable and label-free LC-MS/MS method for assessing drug activity was established, which affords an attractive alternative for those laboratories that do not have a radiation license or capabilities.
