Rapid Determination of Sudan Dyes in chilli products using ultra high performance supercritical fluid chromatography-photodiode array detection

Abstract

A novel, rapid, and reliable ultra-high performance supercritical fluid chromatography (UHPSFC) method was developed to correctly separate and quantitatively determine Sudan dyes in chilli products. The effect of different separation parameters on the retention characteristics of Sudan dyes was investigated. The results showed that diode array detection of Sudan I–II was accomplished at 480 nm, and that of Sudan III–IV at 500 nm. In the analysis of Sudan dyes, the whole analysis time was less than 10 minutes, the method had a limit of detection and limit of quantification of 0.25 μg/mL and 0.50 μg/mL, respectively. All calibration curves had good linearity (r2 > 0.9989) within the tested concentration ranges. The method had intra- and inter-day precision of less than 3.5% and 4.1%, respectively, with a recovery between 96.58% and 104.50%, and a relative standard deviation of less than 4.4%. The method was successfully applied to analyze chilli product sample.