Designer drugs present a new class of drugs structurally and effectively similar to the controlled and illegal drugs. They can have a substantial effect on function of central nervous system in both therapeutic and overdose amounts, possibly resulting into sudden death as limited data on tolerable dosage is available.

Routinely used immunochemical screening methods for analysis of cannabinoids and amphetamines fail to detect the designer drugs, therefore a rapid methodology for their identification and quantification is needed.

Capillary electrophoresis (CE) is a rapid and versatile technique employed in many areas of analytical chemistry. It offers fast and efficient analyses together with low sample consumption which is useful for analysis of biological or forensic samples. However, the hyphenation of CE to mass spectrometry (MS) limits the possibilities of modifying CE separation conditions, e.g. non-volatile additives are unsuitable to use. In the first experiments, we were unable to obtain a separation of the set of selected designer drugs of interest due to their similar electrophoretic behaviour.

Use of monolithic porous layer open-tubular (PLOT) capillaries was studied in order to introduce an interaction with a stationary phase based on lauryl methacrylate-co-ethyleneglycol dimethacralyte. PLOT modified capillaries were first tested using UV‑detection in order to find suitable separation conditions with regard of further transfer to MS detection for selective and sensitive detection for a group designer drugs suspected to be abused in Czech Republic.

The authors are grateful for financial support by Ministry of Health (NT13593 3/2012), Operational Program Research and Development for Innovations - European Regional Development Fund (project CZ.1.05/2.1.00/03.0058) and Program Education for Competitiveness - European Social Fund (project CZ.1.07/2.3.00/20.0018 and CZ.1.07/2.4.00/31.0006).