title: Detection and determination of total amlodipine by high-performance thin-layer chromatography: a useful technique for pharmacokinetic studies.
abstract: A novel analytical method for determination of the total plasma levels (free and protein bound) of the calcium channel blocking agent amlodipine has been developed using a high-performance thin-layer chromatographic (HPTLC) procedure. Detection and quantitation were performed without internal standards. In previously described methods for the estimation of amlodipine by gas chromatography and high-performance liquid chromatography, only the free levels in plasma and serum were quantified at 7% of the total amlodipine level, with the remaining 93% bound to plasma protein and tissue. The present method employs proteolysis of the plasma proteins by incubating plasma for 2 h in pepsin solution. After proteolysis amlodipine is extracted and a known amount of the extract is spotted on precoated silica-gel 60 F254 plates using a Camag Linomat IV autosampler. Amlodipine was quantified using a dual-wavelength TLC scanner. The method provides a direct estimate of the total amlodipine present in plasma.
authors.affiliation: Department of Phytochemistry, Cadila Labs. Ltd., Ahmedabad, India.
authors.forename: K K
authors.initials: KK
authors.lastname: Pandya
authors.forename: M
authors.initials: M
authors.lastname: satia
authors.forename: T P
authors.initials: TP
authors.lastname: Gandhi
authors.forename: I A
authors.initials: IA
authors.lastname: Modi
authors.forename: R I
authors.initials: RI
authors.lastname: Modi
authors.forename: B K
authors.initials: BK
authors.lastname: Chakravarthy
mesh_terms: D017311:Amlodipine / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D010434:Pepsin A; D012680:Sensitivity and Specificity
chemical_list: D017311:Amlodipine; D010434:Pepsin A