Martínez BD, Correa VMT, Oropesa RR, González PO, Ledea LOE

Language: Spanish
References: 10
Page: 550-561
PDF size: 314.42 Kb.

ABSTRACT

Introduction: the evaluation of hormones on endocrinology and clinical biochemistry patients, among others, is presently performed, using inmunoassays with its intrinsic disadvantages such as cross reactions. The application of gas chromatography coupled to mass spectrometry allows increasing the sensitivity and specificity of this analysis.
Objective: to validate an assay for quantitation of 21 hormones by the analytical technique of gas chromatography-mass spectrometry for screening purposes.
Methods: the assay followed a solid-phase extraction using Detectabuse^TM columns and subsequently liquid-liquid extraction at basic pH. Trimethylsilyl derivatives were evaluated on Hewlett-Packard 6890 gas chromatograph coupled to serial 5973 quadrupolar mass spectrometer. The capillary column was HP Ultra-1 (17 m x 0.20 mm x 0.11 µm). Data was gathered following SIM mode (selective ion monitoring).
Results: the results of the validation process adequately fulfilled the acceptance criteria for screening purposes. The assay proved to be specific for all studied compounds, linear (r²= 0.900-0.996) and precise (VC 1.4-9.6 %). The extraction yield was kept at 69-117 %. The robustness assay with varying dissolvent showed extraction yields ranging 69-139 %.
Conclusions: results of the validation process show that the developed assay to simultaneously quantify 21 steroidal compounds in urine is exact, linear, precise, robust and specific for its application in clinical endocrine studies for screening purposes.

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