A New LC/MS/MS Rapid and Sensitive Method for the Determination of Green Tea Catechins and their Metabolites in Biological Samples

✍ Scribed by de Lourdes Mata-Bilbao, Maria; Andrés-Lacueva, Cristina; Roura, Elena; Jáuregui, Olga; Torre, Celina; Lamuela-Raventós, Rosa Maria

• Book ID: 118184345
• Publisher: American Chemical Society
• Year: 2007
• Tongue: English
• Weight: 139 KB
• Volume: 55
• Category: Article
• ISSN: 0021-8561
• DOI: 10.1021/jf0713962

✦ Synopsis

A new rapid and sensitive method has been developed, using liquid chromatography in tandem mass spectrometry (LC-ESI-MS/MS) to identify green tea catechin metabolites in plasma and urine after oral intake of a green tea extract. (-)-Epigallocatechin-3-gallate (EGCG), (-)-epicatechin-3-gallate (ECG), (-)-epigallocatechin (EGC)-glucuronide, (-)-epicatechin (EC)-glucuronide, and EC-sulfate were identified in plasma, whereas in urine only the conjugated catechins were detected (EGCglucuronide, EGC-sulfate, EC-glucuronide, and EC-sulfate). Standard calibration curves prepared in plasma were found to be linear in the range of 10.9-1379.3 nmol/L for EGCG, EGC, ECG, and EC. The accuracy and precision of this assay showed a coefficient of variation of <15%. The method allowed the detection and quantification limits (for 20 µL injection) from 1.1 to 2.6 nmol/L and 3.8-8.7 nmol/L, respectively, in plasma and 0.8-1.8 nmol/L and 2.6-6.0 nmol/L, respectively, in urine. This method can be applied for future clinical and epidemiological studies, allowing the identification of the active metabolites that will reach the target tissues.