Efecto de la adición del estándar interno a muestras de sangre antes de la preparación de manchas de sangre para el análisis de acylcarnitinas.

Abstract

Background: some general factors can influence when determining acylcarnitines through tandem mass spectrometry. Objective: to study the effect of adding the internal standard to blood samples before the preparation of filter paper cards compared with the addition of internal standard after having the filter paper cards prepared for determining acylcarnitines in blood for tandem mass spectrometry. Methodology: two groups of blood samples were prepared: group one without adding internal standard before the preparation of filter paper cards, and group two adding internal standard prior to the preparation of filter paper cards. Subsequently the acylcarnitines profile was measured using tandem mass spectrometry. Results: the recovery of acylcarnitines during extraction for the samples which were not added the internal standard before the preparation of the filter paper cards was 48% while for the samples that were added the internal standard the recovery percentage was 96% which shows a significant difference between the two groups. Conclusion: the ideal extraction process showing the highest acylcarnitines recovery level happens by adding the internal standard to the sample prior to the preparation of filter paper cards. However, for diagnostic purposes, filter paper cards containing samples without internal standard are normally received for the acylcarnitines analysis and, therefore, the method used to add the internal standard after preparing the samples on filter paper without internal standard is appropriate for determining acylcarnitines in blood. Abbreviations: ESI-MS/MS, Electrospray and tandem mass spectrometry.

Keywords:

carnitina

acilcarnitinas

espectrometría de masas en tándem

carnitine

acylcarnitines

tandem mass spectrometry

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