Separation of positional CPP isomers by chiral HPLC-DAD of seized tablets.

Meta-chlorophenylpiperazine, one of the synthetic piperazine-derived designer drugs, is to date controlled as an illicit substance in five European member states. Depending on the position of the chlorine atom, different positional isomers of CPP (ortho-, meta- and para-) are possible. Therefore, there is a need to develop an analytical method for the separation and identification of the three 1-chlorophenylpiperazines in tablets containing CPP. In this work, the position isomers o-, m- and p-CPP were separated by liquid chromatography (HPLC) on a reversed-phase chiral column. Different mobile phase compositions and pH ranges were systematically studied to find optimum chromatographic conditions. Best results were achieved with isocratic mobile phase of triethyl amine buffer and methanol (V/V = 70/30) at pH 9 with a flow rate of 0.8 ml/min. The method was validated in terms of selectivity, linearity, limit of detection and quantification and precision. At last, the developed method was successfully applied on seized ecstasy tablets.