Liquid-chromatographic determination of amoxapine and 8-hydroxyamoxapine in human serum.
We describe a liquid-chromatographic procedure for amoxapine and 8-hydroxyamoxapine, its active metabolite, in serum. We used a mu-Bondapak C18 reversed-phase column and a mobile phase of acetonitrile/water (74/26 by vol) plus 26 microL of n-butylamine per liter. The compounds were measured at 254 nm, with 8-methoxyloxapine as internal standard. Necessary pre-analysis purification consisted of adsorbing the drug from serum onto extraction columns, eluting with 1-butanol/hexane (1/5 by vol), re-extracting into aqueous acid, and from that re-extracting again into the elution-solvent mixture. We prefer this procedure for monitoring both therapeutic and toxic concentrations of amoxapine, because parent drug and metabolite are measured separately.
D000657:Amoxapine / Q000031:analogs & derivatives / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003989:Dibenzoxazepines / Q000097:blood*; D006801:Humans; D013056:Spectrophotometry, Ultraviolet
D003989:Dibenzoxazepines; C035234:8-hydroxyamoxapine; D000657:Amoxapine