Capillary electrophoresis: A new analytical tool for forensic toxicologists

In capillary electrophoresis, electrophoretic or electrokinetic separations are carried out in tiny capillaries at high voltages (10-30 kV), thus achi eving high efficiency (N > 105), resolution power, and mass sensitivity (do wn to 10(-18)-10(-20) moles). The main characteristics of capillary electro phoresis are versatility of application (from inorganic ions to large DNA f ragments), use of different separation modes with different selectivity, lo w demands on sample volume, negligible running costs, possibility of interf acing with different detection systems including mass spectrometry, and the ruggedness and simplicity of the instrumentation. Capillary electrophoresi s applications in the forensic sciences are now rapidly growing, particular ly in forensic toxicology. The present paper briefly describes the basic pr inciples of capillary electrophoresis and presents a selected review of its main applications to the analysis of illicit/controlled drugs in biologic samples. An original analytical approach to the determination of carbohydra te deficient transferrin, a new marker of chronic alcohol abuse, based on c apillary electrophoresis is also described. It is concluded that the peculi ar separation mechanisms and the high complementarity of capillary electrop horesis to chromatography make it a new powerful tool of investigation in t he hands of forensic toxicologists.