Signal Enhancement in the HPLC-ESI-MS/MS analysis of spironolactone and its metabolites using HFIP and NH4F as eluent additives

Abstract

This paper describes an LC-MS/MS method to determine the concentration of spironolactone and its metabolites 7-alpha-methylthiospironolactone and canrenone in blood plasma samples. The resulting assay is simple (using protein precipitation for sample preparation) and sensitive (the lower limit of quantification is close to 0.5 ng/ml) while requiring only 50 μl of plasma, making it especially suitable for analyzing samples obtained from pediatric and neonatal patients where sample sizes are limited. The sensitivity is achieved by using ammonium fluoride as an eluent additive, which in our case amplifies the signal from our analytes in the plasma solution on average about 70 times. The method is fully validated according to the European Medicines Agency’s guideline and used for the measurement of pediatric patients’ samples in clinical trials for evaluating oral spironolactone’s and its metabolites’ pharmacokinetics in children up to 2 years of age.

Multi-residue analysis using liquid chromatography tandem mass spectrometry for detection of 20 coccidiostats in poultry, livestock, and aquatic tissues

“…Such compounds can be bipolar molecules that, having a surfactant activity, can reduce the surface tension of the ion-spray droplets especially at highly aqueous compositions thus facilitating the release of analyte ions from the ion-spray micro-droplets (either via direct release from the droplet surface or indirectly through the facilitation of coulomb explosions). This results in a higher yield of free ions released into space within the ion-source [ 28 , 29 ]. In this study, we assumed the ME of imidocarb obtained by chemical properties than real ME.…”

Development and validation of a fast and sensitive UHPLC‐ESI‐MS method for the simultaneous quantification of spironolactone and its metabolites in ocular tissues

“…As far as we are aware, there is no available validated UHPLC–MS method in the literature allowing the simultaneous detection and quantification of spironolactone and its main metabolites, TMSPL and CAN, in corneal tissues, within a relatively short runtime of 5 min. Indeed, recent LC–MS/MS methods have been published for the quantification of spironolactone and its metabolite, CAN, in human plasma but these methods did not include TMSPL (Dong, Xu, Zhang, Tian, & Chen, ; Lee, An, Kim, Shim, & Lee, ; Sora, Udrescu, Albu, David, & Medvedovici, ; van der Nagel, Versmissen, Bahmany, Gelder, & Koch, ; Vlase, Imre, Muntean, Achim, & Muntean, ) and the runtimes were relatively long (> 10 min; Dong, Xu, Zhang, Tian, & Chen, ; Sora, Udrescu, Albu, David, & Medvedovici, ; Takkis et al, ). Including TMSPL in the analytical method is of great importance, especially now that it is recognized as being one of the main active metabolites of spironolactone (Kaukonen, Vuorela, Vuorela, & Mannermaa, ; Sandall, Millership, Collier, & McElnay, ; Sora, Udrescu, Albu, David, & Medvedovici, ) and contributes significantly to the pharmacological effects observed (Kaukonen, Vuorela, Vuorela, & Mannermaa, ; Los, Pitzenberger, Ramjit, Coddington, & Colby, ; H. W. Overdiek, Hermens, & Merkus, ; Sandall, Millership, Collier, & McElnay, ).…”

Automated Supported Liquid Extraction for the analysis of a panel of 12 endogenous steroids in human plasma by LC-MS/MS

“…Exploring chlorobutane as an alternative elution solvent may lead to an improvement in progesterone recovery [42]. Including more compounds in the steroid biosynthetic pathway is also desirable, such as estrogens, aldosterone and DHEAS, by modifying the mobile phase of the LC system with ammonium fluoride, which is reported to enhance negative ion formation, post separation [45]. Successfully enhancing negative ion formation would address ion suppression issues in low abundance steroids and result in a broader steroidogenic pathway method.…”