Rhodamine B in Chili Extract

Safe Detection Using Purospher® HPLC Columns

Red chili extract (red paprika oleoresin) is highly stable in light and heat, and is soluble in oil, acetone, chloroform, n-hexane and alcohol. After emulsification, the extract can be transformed into a water-soluble or water-separate product. Sudan dyes, which belong to the class of synthetic azo dyes, have been previously added to bell pepper and chili powders in order to intensify their color. However, their metabolites are considered to be both carcinogens and teratogens. Consequently, the EU and US have banned the use of these colors as food additives. Nevertheless, these dyes are still occasionally used in some countries. Accurate analysis techniques are necessary in order to avoid potential health risks. Merck's Purospher® HPLC columns are ideal for the detection of Rhodamine B in chili extract. The columns offer highly reliable results, with excellent separations and outstanding peak symmetry.

Application Example

Separation of Rhodamine B in chili extract

Column	Purospher® STAR RP-18 endcapped (5μm) LiChroCART® 250-4,6 HPLC column (150252)
Precolumn	Purospher® STAR RP-18 endcapped (5μm) LiChroCART® 4-4 (150250)
Oven temperature	40 °C
Injection volume	10 μL
Flow Rate	1 mL /min
Eluent A	Phosphoric acid (1 mL 85% Phosphoric acid in to 1 L of Water)
Eluent B	Acetonitrile
Gradient	Time (min)	Eluent A	Eluent B	Flow Rate (mL/min)
	0.0 0.0 15.0 20.0 21.0 35.0	58 58 20 20 58 58	42 42 80 80 42 42	1 1 1 1 1 1
Detection	Fluorescence
Wavelength	Wavelength
PMT Voltage	Medium
Sample Rate	400 ms
Time Constant	1 sec
Sample	0.6248 g Oleoresin oil in 5 mL eluent (Oleoresin sample contaminated with 140 ppb Rhodamine B)

Specification of Purospher® RP-18 endcapped