Antidepressants in serum determined by isolation with two on-line sorbent cartridges and liquid chromatography.
A selective method for measuring tricyclic antidepressants in serum is reported. A single assay can be done within ca. 30 min and eight samples can be assayed in less than 150 min. A 1-ml serum sample was diluted and the drugs were extracted from it by passage through a graphitized carbon black (Carbopack B) cartridge. After one washing, this cartridge was connected on line to another one containing a silica-based strong acid exchanger. The tricyclics were removed from the Carbopack surface and selectively readsorbed onto the cation-exchange surface by passing 4 ml of methylene chloride-methanol (60:40, v/v) through the two cartridges. After another wash, the drugs were desorbed from the cation-exchange surface with 0.8 ml of acetonitrile-methanol-water (72:18:10, v/v) saturated with potassium chloride. An aliquot of this solution was chromatographed on a cyano column, and the absorbance of the effluent was measured at 215 nm. The mean analytical recoveries of tricyclic antidepressants added to serum within the range 10-200 micrograms/l exceeded 90%, except for 8-hydroxyamoxapine (mean recovery 85.3%) and amoxapine (mean recovery 83.8%) at the lowest serum concentration considered.
Carfagnini
G
G
Dipartimento di Chimica, Università La Sapienza di Roma, Italy.
Di Corcia
A
A
Marchetti
M
M
Samperi
R
R
D000929:Antidepressive Agents, Tricyclic / Q000097:blood*; D002853:Chromatography, Liquid; D006801:Humans; D007202:Indicators and Reagents; D013056:Spectrophotometry, Ultraviolet
D000929:Antidepressive Agents, Tricyclic; D007202:Indicators and Reagents