A new, highly sensitive capillary zone electrophoresis methodfor determination of huperzine A, a perspective prophylactic antidote against militarily important nerve agents and anti-Alzheimer's disease drug, was developed. Huperzine A is an alkaloid isolated from the Chinese club moss Huperzia serrata. The absorption spectra and electrophoretic behaviour of the compound were studied. The compound shows two absorption maxima (λ_max 230 and 310 nm). The protonation constant was determined by spectrophotometry and capillary zone electrophoresis (CZE) and the recommended value is pK = 7.70 ± 0.07. A CZE method for the determination of huperzine A in pharmaceutical tablets and serum has been developed. This method is based on separation of the compound as a protonated species with electrophoretic mobility determined as 50.7x 10^-9 m²V^-1S^-1. The optimal separation conditions were.“ acetate bujfer (pH4.60,' 20 mM) as a background electrolyte, a separation voltage of 20 kV,“ a temperature of 25°C, hydrodynamic injection 10 s and detection at wavelengths 230 and 310 nm. The analyses were run in an uncoated fused-silica capillary with a total length of 47.5 cm (39.0 cm to the detector) and the 75 μm I.D. Detection limit was found to be 70 μg/l. The method of huperzine A determination was applied for analysis of two pharmaceutical products. The results were found to be in good agreement with the declared amount. The precision of the method is ± 2.30 % rel. The method for determination of huperzine A in serum was also developed with a detection limit of 110 ug/l which is applicableforpharmacokinetics and therapeutic drug monitoring of this compound

Keywords: Huperzine A; Prophylactic antidote against organophosphate nerve agents; Alzheimer’s disease; Capillary zone electrophoresis