Rapid analysis of methylated xanthines in teas by an improved high-performance liquid chromatographic method using a polyvinylpolypyrroridone pre-column
| Autor: | Hideki Horie, Hideo Nakakuki, Yuji Yamauchi, Katsunori Kohata |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Chromatography
Tea Chemistry Organic Chemistry Povidone General Medicine Standard solution Methylation Biochemistry High-performance liquid chromatography Analytical Chemistry chemistry.chemical_compound Polyphenol Xanthines medicine Spectrophotometry Ultraviolet Sample preparation Solid phase extraction Caffeine Theobromine Quantitative analysis (chemistry) Chromatography High Pressure Liquid medicine.drug |
| Zdroj: | Journal of Chromatography A. 848:523-527 |
| ISSN: | 0021-9673 |
| DOI: | 10.1016/s0021-9673(99)00418-5 |
| Popis: | We have developed a new high-performance liquid chromatography (HPLC) method for the analysis of methylated xanthines in tea by removing polyphenols using a polyvinylpolypyrroridone (PVPP) pre-column. The PVPP pre-column was connected with the upstream of analytical column to remove catechins in tea extract. Using this pre-column, caffeine and theobromine in tea, which belong to methylated xanthines, could be rapidly determined in less than 10 min with an isocratic solvent system. RSDs of standard solutions of caffeine and theobromine were about 0.3 and 0.3% for the retention time, and were about 1.6 and 2.5% for the peak area. The quantitation curves of caffeine and theobromine were linear from 5 to over 1000 ng. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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