Reference

Analysis of amoxapine, 8-hydroxyamoxapine, and maprotiline by high-pressure liquid chromatography

Analysis of amoxapine, 8-hydroxyamoxapine, and maprotiline by high-pressure liquid chromatography. Ketchum, Catherine; Robinson, C. A.; Scott, J. W. (Dep. Pathol., Univ. Alabama, Birmingham, AL 35294, USA). Ther. Drug Monit., 5(3), 309-12 (English) 1983. CODEN: TDMODV. ISSN: 0163-4356. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Two high-pressure liq. chromatog. 10262-69-8 and 61443-78-5 which are cas registry numbers are also used here. procedures are presented for the routine anal. of two new antidepressant drugs, amoxapine (I) [14028-44-5] as well as its active metabolite and maprotiline [10262-69-8]. Recovery rates were excellent with both methods of extn. Method 1, for I and its metabolites, was linear up to 1,000 ng/mL. Sensitivity for the parent drug was 10 ng/mL and, for the active metabolite, 25 ng/mL. Within-run coeffs. of variation (CV) were 4.57% for 8-hydroxyamoxapine [61443-78-5] and 3.84% for I. Method 2, for maprotiline, was linear from 10 to 1,000 ng/mL. Intraassay CV was 3.2%. Reliable, yet simple, methods form monitoring these drugs are needed in order to establish firmly the pharmacol. data important to appropriate patient therapy. .

Liquid chromatographic separation of antidepressant drugs: II

Liquid chromatographic separation of antidepressant drugs: II. Amoxapine and maprotiline. Beierle, Floyd A.; Hubbard, Richard W. (Sch. Allied Health Prof., Loma Linda Univ., Loma Linda, CA 92354, USA). Ther. Drug Monit., 5(3), 293-301 (English) 1983. CODEN: TDMODV. ISSN: 0163-4356. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) The simultaneous serum anal. of amoxapine (AMOX)(I) [14028-44-5] and its major metabolite 8-hydroxyamoxapine (8-OH AMOX) [61443-78-5], and maprotiline (MAP)(II) [10262-69-8] and its major metabolite desmethylmaprotiline (D-MAP) [5721-37-9] by high-performance liq. chromatog. (HPLC) and UV detection is described. AMOX and 8-OH AMOX were detected at 254 nm at 0.01 absorbance units full scale (AUFS). MAP and D-MAP were detected at 214 nm at 0.05 AUFS. Serum (1.0 mL collected in plastic) extn. was by Bond-Elut C18 columns. The compds. of interest were eluted from the columns with 10 mM methanolic ammonium acetate. The eluates were evapd. at 56-58° and reconstituted with 200 mL of mobile phase. The mobile phase was abs. EtOH-MeCN-tert-butylamine (:0.05), and the flow rate was 2.0 mL/min.In this article, certain chemicals are used. Some of their cas registry numbers are 14028-44-5 and 5721-37-9 Abs. recoveries range from 97 to 100% for all compds. HPLC was done on a 5-mm (4.6 ′ 250 mm) silica-packing column (normal phase). Sepns. on a 10-mm silica column (3.9 ′ 300 mm) are also discussed. Peak height ratios using trimipramine as the internal std. were linear for each drug between 25 and 1080 ng/mL. AMOX and 8-OH AMOX ratios with promazine as the internal std. were linear between 25 and 1080 ng/mL. Detection limits were 3 ng/mL for AMOX and 8-OH AMOX, 12 ng/mL for D-MAP, and 15 ng/mL for MAP. Coeffs. of within-day and day-to-day variation at 3 concn. levels were less than 10.8% and 10.5%, resp., for all compds. Correlations of AMOX, 8-OH AMOX, and MAP sample assays using gas chromatog. (or gas chromatog.-mass spectrometry) and this method were compared. Steady-state daily dosages and corresponding serum levels are presented for 7 patients. AMOX and 8-OH AMOX concns. for 37 patients are given; these show that the ratios of these compds. are highly variable between patients. MAP and D-MAP concns. for 30 patients show that D-MAP can be a significant fraction of the circulating drug. Assay time for 8-OH AMOX/AMOX was 6.5 min and <13 min for D-MAP/MAP. This assay can be used in correlating serum levels with clin. effects, compliancy, and pharmacokinetic studies. .