Rapid Determination of Carotenoids in Spirulina Dietary Supplement Products by Ultra Performance Convergence Chromatography with Photodiode Array Detector

KeyWord:carotenoids  ultra performance convergence chromatography(UPC2)  dichloromethane-ethanol extraction  spirulina dietary supplement products

Abstract:

      A quick ultra performance convergence chromatography(UPC2) with photodiode array detector method was developed for the simultaneous determination of three carotenoids(e.g.¦Â-carotene,zeaxanthin and lutein) in spirulina dietary supplement products.Effects of chromatogramic column, co-solvent,backpressure,column temperature and extraction solvent were optimized.The optimal conditions were as follows:The samples were extracted ultrasonically with dichloromethane-ethanol(2¡Ã1),followed by clean-up of extract using 0.22 ¦Ìm GHP filter.The separation of compounds was carried out on an ACQUITY UPC2 HSS C18 SB column(150 mm¡Á3.0 mm£¬1.8 ¦Ìm) by gradient elution with carbon dioxide and methanol system.The column temperature was set at 40 ¡æand the backpressure was 2 000 psi.The quantification analysis was achieved by the external standard method.Good linear relationships were obtained for 3 carotenoids in the certain concentrations with correlation coefficients not less than 0.999 3.The limits of detection(LODs) of 3 carotenoids were in the range of 0.012-0.035 mg/g,and the limits of quantitation(LOQs) were in the range of 0.040-0.120 mg/g.The mean recoveries ranged from 82.5%to 95.7%at different spiked levels with relative standard deviations(RSDs) of 7.6%-9.8%.The method is rapid and accurate,and could be used for the analysis of carotenoids in spirulina dietary supplement products£®