Amphetamines are a class of illegal drugs that exhibit strong central nervous system stimulant effect. Therefore several US and European states have set up a cut-off value in urine or blood [e.g. France and Virginia (respectively 50ng/mL and 100ng/mL of blood)]. These values are used to determine if drivers are under influence of (Meth)amphetamine.
For such low concentrations, a clean up step is crucial in order to improve the sensitivity, the reliability and the specificity before LC analysis.