Determination of captopril in biological samples by high‐performance liquid chromatography with ThioGlo™3 derivatization

Abstract

Captopril, a well-known angiotensin converting enzyme (ACE) inhibitor, is widely used for treatment of arterial hypertension. Recent studies suggest that it may also act as a scavenger of free radicals because of its thiol group. Therefore, the present study describes a rapid, sensitive and relatively simple method for the detection of captopril in biological tissues with reverse-phase HPLC. Captopril was first derivatized with ThioGlo 3 [3H-Naphto[2,1-b]pyran,9-acetoxy-2-(4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)phenyl-3-oxo-)]. It was then detected by fluorescence-HPLC using an Astec C(18) column as the stationary phase and a water:acetonitrile:acetic acid:phosphoric acid mixture (50:50; 1 mL/L acids) as the mobile phase (excitation wavelength, 365 nm; emission wavelength, 445 nm). The calibration curve for captopril was linear over a range of 10-2500 nM and the coefficient of variation acquired for the within- and between-run precision for captopril was 0.5 and 3.8%, respectively. The detection limit of captopril with this method was found to be 200 fmol/20 microL injection volume. Its relative recovery from biological samples was determined to the range from 93.3 to 105.3%. Based on these results, we believe that our method is advantageous for captopril determination.

Recent advances in separation and detection methods for thiol compounds in biological samples

“…Several drugs, i.e., TP in biological samples (plasma, lung, liver, kidney and brain in mice) [63], 2-mercaptoethane sulfonate (MESNA) in biological samples (lung, liver, kidney and brain) [64], captopril in rat plasma [65], and sodium thiosalicylate in mice plasma [66], were successfully determined by the LC-FL method, as well as biological thiols [67]. The reaction scheme of ThioGlo TM 3 with captopril is shown in Fig.…”

A Liquid Chromatography/Tandem Mass Spectrometric Method for Determination of Captopril in Human Plasma: Application to a Bioequivalence Study

“…Several liquid chromatographic methods were applied for determination of captopril in plasma using UV detection, (Bald and Sypniewski, 1997;Bald et al, 1996;Ding et al, 2001;Foroutan et al, 2003;Hadjmohammadi et al, 2008;Huang et al, 2006;Jankowski et al, 1995;Li et al, 1996 ;Sultan et al, 2013;Sypniewski and Bald, 1996) fluorescence detection (Aykin et al, 2001;Kok et al, 1997;Tache et al, 2002) or mass detection (Borges et al, 2006;Chik Z et al, 2014;Du, 2007;Rezende et al, 2007;Salem et al, 2005;Vancea et al, 2009) using either protein precipitation, solid phase extraction or liquid-liquid extraction for sample preparation prior to analysis.…”

Determination of WR-1065 in human blood by high-performance liquid chromatography following fluorescent derivatization by a maleimide reagent ThioGlo™3

“…ThioGlo TM 3 was used as a derivatizing agent because this reagent has several advantages such as a low fluorescence background, a high quantum yield after reacting with free thiols, a fast reaction time, and a slow hydrolysis rate of the adduct [15,16]. Furthermore, ThioGlo TM 3 has been used as a fluorescent probe, in combination with HPLC, to successfully analyze a number of free thiol substrates and drugs in biological samples such as glutathione [17], captopril [16] and MESNA [18].…”