Attention:

Certain features of Sigma-Aldrich.com will be down for maintenance the evening of Friday August 18th starting at 8:00 pm CDT until Saturday August 19th at 12:01 pm CDT.   Please note that you still have telephone and email access to our local offices. We apologize for any inconvenience.

LC/MS Analysis of Artificial Food Colorants Cochineal Red A and Azorubine in Yoghurt on Chromolith® FastGradient RP-18 endcapped

LC/MS Analysis of Artificial Food Colorants Cochineal Red A and Azorubine in Yoghurt on Chromolith® FastGradient RP-18 endcapped

Conditions

column Chromolith FastGradient RP-18, 5 cm x 2.0 mm I.D, 2 µm particles (1.52007.0001)
column temp. 25 C
mobile phase [A] acetonitrile; [B] 20 mM ammonium acetate, pH 4.7 in water
gradient 2.5 to 50% A in 6 min; held at 50% A for 2 min
flow rate 0.4 ml/min
pressure 856-899 psi (59-62 bar)
injection 1 µl
detector ESI-MS(-) (m/z range 100-550), BPC

Description

Categories Analytical Chromatography, Dyes
Featured Industry Food and Beverages
Legal Information Chromolith is a registered trademark of Merck KGaA, Darmstadt, Germany
Other Notes Sample Prep: 10 g of yoghurt was mixed with 30 mL acetonitrile, stirred for 30 min and centrifuged for 20 min at 4500 rpm. Acetonitrile was removed (TurboVap II, 90 min, 40 °C, 1 bar nitrogen) and solution was filtered using 0.45 μm filter. sample was spiked with E-124 (Cochineal Red A, 69.44 mg in 50 mL water) and E-122 (Azorubine, 3.46 mg in 10 mL water) stock solutions in a 10:2:3 ratio (v/v)
suitability application for LC-MS

Materials

     
Related Links