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Fia-spectrophotometric determination of thiamine after UV-irradiation
1Department of Analytical Chemistry, Faculty of Chemistry, University of Bucharest, Bul. Carol I, 13, Bucharest 70031, Romania.
Abstract:
The determination of thiamine was carried out by UV-photodegradation in a single-line flow-injection assembly. The UV-photodegradation of thiamine was carried out in the coil of the injection valve, constituted of a PTFE tubing, half of its length being helically coiled around a UV lamp. A peak with two adjoining maxima was produced by injection, corresponding to the absorbance of the irradiated and non-irradiated sample. The analytical parameter is the difference between the two peaks, measured at 264 nm. The calibration graph is linear over the 1.2-30 mug/ml range of thiamine hydrochloride in 0.1M HCl. The influence of certain admixed substances was studied and the method was tested for the determination of thiamine in tablets.
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