Search

• Aldosterone was quantified by LC/ESI-MS/MS for primary aldosteronism treatment. • Six adrenal venous serum samples were collected from each patient by ssAVS technique. • A sextet of Girard reagents was employed for the sample-multiplexing. • Aldosterone in 6 ssAVS samples could be quantified by a single run. • The method was successfully used to analyze the ssAVS samples from 8 patients. [Display omitted] The accurate quantification of aldosterone (ALD) in adrenal tributary venous serum/plasma collected by a super-selective adrenal venous sampling (ssAVS) technique has become a definitive procedure to identify the forms (laterality) of primary aldosteronism (PA) and the location of the affected segment(s), and to subsequently make the treatment decision. In this study, a stable isotope-dilution LC/ESI-MS/MS-based method was developed and validated for the determination of the ALD concentrations of the six ssAVS serum samples during a single run. A sextet of Girard reagents was used to convert ALD to the derivatives having different masses for each sample. Based on the validation tests, satisfactory specificity, precision and accuracy were observed and the matrix effect was found to be acceptable. The developed method was used for the analysis of the ssAVS serum samples from eight PA patients. The batch analysis of the six samples permitted the direct comparison of the ALD concentrations between the samples and enhanced to determine the laterality and location of the affected segment(s). The total analysis time after the sample purification was also reduced to 1/3 for the 24 samples by the sample-sextuplex procedure, which was also an advantage of the developed method. [ABSTRACT FROM AUTHOR]

• A quantitative MALDI-MS/MS method was developed for the serum cortisol. • Charged derivatization was employed for increasing the sensitivity. • Reproducible (intra- and inter-assay RSD ≤ 7.4%) quantification using a 20-μL sample. • The measured values by MALDI-MS/MS agreed well with those by LC/ESI-MS/MS or ECLIA. • The method was used for the analysis of peripheral and adrenal serum samples. Cortisol (CRT), the main glucocorticoid in humans, plays a crucial role in many physiological processes, therefore, the measurement of its serum level is of great clinical significance. Matrix-assisted laser desorption/ionization-tandem mass spectrometry (MALDI-MS/MS) might be an effective approach for the quantification of CRT in serum due to its attractive properties, i.e. , high specificity, ease of use, ruggedness and rapid analysis. In this study, we developed a method to quantify the serum CRT by MALDI-MS/MS. This method employed the derivatization using a Girard-type reagent, 1-(hydrazinocarbonylmethyl)isoquinolinium chloride, which compensated for the lack of sensitivity. This method enabled the reproducible quantification of the serum CRT using a 20-μL sample (intra- and inter-assay relative standard deviations, 7.4% or lower), and the measurable range was 25–500 ng/mL. The serum CRT concentrations determined by the newly-developed MALDI-MS/MS method agreed well with those by liquid chromatography/electrospray ionization-MS/MS or electrochemiluminescence immunoassay. The MALDI-MS/MS method was used for the analysis of peripheral venous serum samples of healthy subjects and adrenal venous serum samples of patients with primary aldosteronism, and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]