This document describes a method for analyzing Sudan red in diesel oil using high-performance liquid chromatography (HPLC). The method can be used to identify and quantify Sudan red by measuring its absorption spectrum.
This document details a High-Performance Liquid Chromatography (HPLC) method for identifying and quantifying Sudan Red, an azo-dye used to color diesel fuel, in diesel samples. The method is designed for cases where visual inspection is impossible due to the dark color of the fuel. It utilizes an Agilent 1100 Series system equipped with a diode array detector to obtain complete spectra for identification.
| Column | 100 x 4 mm Hypersil BDS, 3 um |
|---|---|
| Mobile Phase A | Water, pH = 2.16 with H2SO4 |
| Mobile Phase B | Acetonitrile |
| Gradient | at start 70 % B, at 10 min 99 %B |
| Flow Rate | 0.8 ml/min |
| Oven Temp | 35 °C |
| Detection wavelength | 535/40 nm |
| LOD | 0.8 to 0.9 ng for signal/noise = 2 |
| Linearity | min 1 ng to 1 ug |
The analysis uses an Agilent 1100 Series system including a degasser, quaternary pump, autosampler, thermostatted column compartment, and diode array detector.
The detection wavelength is set to 535/40 nm.