Analysis of Vitamin B2 in Saffron Stigmas (Crocus sativus L) by Capillary Electrophoresis Coupled with Laser-Induced Fluorescence Detector

Saffron is the most expensive spice derived from the flower of Crocus sativus. The purpose of this study is to determine the vitamin B2 level in saffron using a trustable, easy, and sensitive analytical method and therefore to provide the missing information on the nutritional value of this spice. In our current study, by separating with the fast separation technique capillary electrophoresis (CE) and using a laser-induced fluorescence (LIF) detector which is both sensitive and discriminating from other UV active ingredients, the precise determination of vitamin B2 in saffron was achieved. Saffron samples were extracted by boiling water and directly injected to the separation buffer, borate at pH 9.5. The repeatability of the peak areas (%RSD) of riboflavin for intraday and interday was in the satisfactory range of equal to or less than 2.32 and 4.70 %, respectively. The limit of detection (LOD) and limit of quantification (LOQ) values for the method were 4.15 and 13 nM, respectively. Determination of riboflavin was performed by the standard addition method. Riboflavin contents of five saffron samples from two of the biggest producers in the global market (Iran and Spain) were in the range of 5.02–13.86 μg/g.