ビタミンB_1測定法の現状と課題(<特集>ビタミン測定法の現状と課題[III])

抄録

As for the measurement of the content of vitamin B_1 in foods and biological samples, BrCN-thiochrome fluorescent method was used as a standard method for a long time up to the first half of 1980s. However, the fluorescent detection method by HPLC has become a mainstream nowadays. The measurement of vitamin B_1 by HPLC is classified into two methods, pre-column derivatization method and post-column derivatization method, by the timing of adding the thiochrome (Thc) regent whether it is added before the passage of the HPLC column or after. In the measurement of thiamin in whole blood, the both methods showed fine chromatographic separation with a single peak. The retention times by pre- and post- column derivatization methods were 5.1 minutes and 5.5 minutes, respectively. Regarding the precision, the CV by the two methods were 2.2% and 3.1%, respectively, and therefore the accuracy of the two methods was regarded to be comparable. However, it was proved that the correlation of the two methods was r=0.875, y=0.804x+8.423. Thus, post-column derivatization method tended to show lower value than the other method. Therefore, in the evaluation by HPLC analysis for clinical diagnosis and nutritional surveillance, it would be needed to conduct HPLC by employing the same method, pre- or post-column derivatization method.