title: Trimipramine determination in pharmaceutical preparations with an automated multicommutated reversed-flow system.
abstract: In this work an automated multicommutated flow methodology was implemented for the spectrophotometric determination of trimipramine in pharmaceutical preparations by oxidation with ammonium monovanadate in acidic medium. The developed procedure exploits a new approach for sample/reagent intermixing by combining binary sampling with flow-reversal. Rather than inserting the sample as a single continuous volume the intercalation of multiple small sample and reagent aliquots, under a time-based control, created multiple reaction interfaces that promoted reaction zone homogenisation even in limited dispersion conditions. Additionally, the reaction interfaces were reversed, increasing mutual zone penetration, which contributed to a faster reaction development while assuring a low dispersion pattern. A linear range of determination was verified for trimipramine concentrations between 1.0 and 18.0 microg ml(-1) with a relative standard deviation (n=10) lower than 1.69% and a sample throughput of about 26 samples per hour. The results were in agreement with those obtained by the reference procedure with relative deviations lower then 2.37%.
authors.affiliation: Requimte/Departamento de Química-Física--Faculdade de Farmácia (UP), Rua Aníbal Cunha, 164 4050-047 Porto, Portugal.
authors.forename: João A V
authors.initials: JA
authors.lastname: Prior
authors.forename: João L M
authors.initials: JL
authors.lastname: Santos
authors.forename: José L F C
authors.initials: JL
authors.lastname: Lima
mesh_terms: D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000737:chemistry; D019999:Pharmaceutical Solutions / Q000032:analysis / Q000737:chemistry; D013053:Spectrophotometry / Q000295:instrumentation / Q000379:methods; D014299:Trimipramine / Q000032:analysis* / Q000737:chemistry*
chemical_list: D004364:Pharmaceutical Preparations; D019999:Pharmaceutical Solutions; D014299:Trimipramine