Abstract: This study aimed to establish a new rapid and simple method for the quantitative determination of riboflavin in biological samples, namely molecular fluorescence differential standard addition method. The results showed that the riboflavin content in yolks determined by the method was 402 μg/100 g with relative standard deviation (RSD) of less than or equal to 1.5% (n = 6). The recoveries of the analyte from spiked samples ranged between 92.0% and 104%. The limit of detection (LOD) of the method was 5.76 × 10-3 μg/mL and the limit of quantitation (LOQ) was 1.92 × 10-2 μg/mL. This method was tested under the same conditions without background interference and without the need to prepare a working curve and to remove impurities by column chromatography. It was rapid, accurate, simple, practical and suitable for the determination of vitamin B2 in egg yolks.

Key words: molecular fluorescence, differential standard addition method, egg yolks, vitamin B2