Abstract
The previous paper had shown that the red fluorescent product was formed by reaction of thiolized-thiamine with cuprous ion, and it could be applied to the analysis of thiamine. A new method for the fluorometric determination of thiamine propyl disulfide (TPD) and thiamine tetrahydrofurfuryl disulfide (TTFD) with cuprous ion was tried : The sample solution was adjusted with NaOH solution at pH 10.5〜11.5 after adding Na_2S_2O_4 solution, and then heated for 30 seconds at 70℃. Thus reduced thiamine solution with the cuprous ion reagent in cooling. The reaction product of cuprous ion reagent was reacted thiamine system was extracted with iso-amyl alcohol containing isoamyl gallate as a stabilizer, and then intensity of red fluorescence of isoamyl alcohel layer was measured at 640mμ (excited by 320mμ ray). Thiamine and TPD or TTFD in their mixture could be determined respectively with the combination of the previous method and this method.
