Separation and determination of aminohalogenbenzophenones by high-performance liquid chromatography with electrochemical detection.
A high-performance liquid chromatographic method with electrochemical detection has been developed for the determination of three aminohalogenbenzophenones: 2-amino-2',5-dichlorobenzophenone, 2-amino-5-chlorobenzophenone and 2-amino-5-bromo-2'-fluorobenzophenone, metabolites of benzodiazepinooxazoles and other psychotropic drugs. A mobile phase of methanol-water (65:35), containing 5 mM KH2PO4 appeared to be the optimal when a 4-microns, 60-A Nova-Pak C18 column and a flow-rate of 0.75 ml/min (130 bar) were used. The temperature was optimized at 30 degrees C. The amperometric detector, equipped with glassy carbon electrode, was operated at 1.3 V versus Ag/AgCl in the DC mode. The method was applied to the determination of these compounds at two concentration levels: ppm and ppb (ng/cm3) using 2-amino-5-chlorobenzophenone as internal standard. The limit of determination was 750 pg/ml of biological fluid for each compound, and recoveries greater than 97% were obtained for spiked samples of urine and serum, using C18 Sep-Pak cartridges in the sample clean-up procedure.
Rodríguez
F J
FJ
Departamento de Quimica Analitica, Facultad de Ciencias, Universidad del Pais Vasco, Bilbao, Spain.
Jiménez
R M
RM
Alonso
R M
RM
D014151:Anti-Anxiety Agents; D001569:Benzodiazepines; D001570:Benzodiazepinones / Q000378:metabolism; D001577:Benzophenones / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry; D006801:Humans
D014151:Anti-Anxiety Agents; D001570:Benzodiazepinones; D001577:Benzophenones; D001569:Benzodiazepines; C000425:oxazolam; C014317:2-amino-5-chlorobenzophenone; C005522:cloxazolam; C018779:haloxazolam