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Análisis de Trazadores de Isótopos Estables de Vitamina A mediante LC-MS/MS
Georg Lietz1, Dan Astley2, Alice Goddard3
1Human Nutrition and Exercise Research Centre, Newcastle University; georg.lietz@newcastle.ac.uk.
Journal of visualized experiments : JoVE
|January 19, 2026
Resumen
El método de dilución isotópica de retinol (RID) mide con precisión los niveles de vitamina A utilizando espectrometría de masas. Esta técnica mejora la velocidad y la sensibilidad para una estimación precisa de las reservas corporales totales (TBS) en humanos.
Área de la Ciencia:
- Bioquímica
- Química Analítica
- Nutrición Humana
Sus antecedentes:
- La evaluación precisa de las reservas corporales totales (TBS) de vitamina A es crucial para la salud humana.
- El método de dilución isotópica de retinol (RID) se basa en la medición precisa de las proporciones isotópicas del plasma.
Objetivo del estudio:
- Describir un método LC-MS/MS rápido, sensible y simultáneo para el análisis de retinoides marcados y no marcados.
- Optimizar la cuantificación del retinol para el método RID, evitando una extracción y derivatización prolongadas.
Principales métodos:
- Dilución isotópica estable utilizando retinol marcado (13C o 2H).
- Cromatografía líquida de alta resolución-espectrometría de masas en tándem (LC-MS/MS) con ionización química a presión atmosférica (APCI).
- Preparación de muestras de plasma que implica extracción con disolvente para el aislamiento del retinol.
Principales resultados:
- Alta sensibilidad lograda con límites de detección de retinol de hasta 6 fmol en columna.
- LC-MS/MS permite el análisis simultáneo de retinoides marcados y no marcados, distinguiendo el retinol de los ésteres de retinol.
- Aislamiento y cuantificación exitosos de retinol endógeno y marcado a partir de plasma.
Conclusiones:
- LC-MS/MS proporciona un enfoque eficiente y sensible para la cuantificación del retinol en el método RID.
- El método descrito mejora la precisión y la eficiencia de la estimación de las reservas corporales totales (TBS) de vitamina A.
- Esta estrategia analítica apoya la mejora de la evaluación nutricional y las estrategias de salud pública relacionadas con el estado de la vitamina A.
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