Optimizirano određivanje lorazepama u humanom serumu visokotlačnom tekućinskom kromatografijom

The present research was designated to evaluate a rapid and sensitive method for determining low concentrations of the highly active drug lorazepam in serum. Isolation of the drug from biological fluid after addition of nordazepam as the internal standard was achieved using a simple liquid-liquid extraction with dichloromethane and the extracted compounds were quantified by high-performance liquid chromatography. Chromatographic separation on a reversed phase column containing a stationary phase with low silanol activity resulted in a perfectly symmetrical peak with a tailing factor of 1.0. The limit of quantitation in serum is 2.5 ng mL-1 for both lorazepam and internal standard. The procedure is rapid and sensitive enough for determination of lorazepam in serum.U radu se vrednuje brza i osjetljiva metoda za određivanje niskih koncentracija lorazepama u serumu. Lorazepam je izoliran iz seruma ekstrakcijom diklormetanom, zajedno s nordazepamom, koji je upotrebljen kao interni standard i zatim određivan visokotlačnom tekućinskom kromatografijom. Kromatografskim razdjeljivanjem na reverzno-faznoj koloni sa stacionarnom fazom s niskom aktivnošću silanola dobiveni su potpuno simetrični signali faktorom završnog povlačenja 1,0. Granica određivanja u serumu je 2,5 ng mL-1 za lorazepam i interni standard. Metoda je brza i dovoljno osjetljiva za određivanje lorazepama u serumu