The use of evaporative light scattering detection (ELSD) within in the field of HPLC is continuously growing, due to its universal nature.
The technique is a powerful tool for detecting any sample that is less volatile than the mobile phase, irrespective of the optical properties of the compounds of interest. The ELS detector offers distinct advantages over UV/Vis and Refractive Index (RI) detection for particular applications, and is complementary to
LC-Mass Spectrometry.
These advantages of ELSD are highlighted in the analysis of biodiesels, which contain complex mixtures of fatty acids, lipids and esters, all of which possess weak or no UV chromophore. Typically, fatty acids and lipids are often derivatised to enhance their UV absorbance or to facilitate their detection by GC-MS.
Interest in biodiesels has increased over recent years, because they are renewable fuels that can be produced from almost any vegetable oil, animal fat or used cooking oil. Biodiesel has similar properties to ordinary diesel fuel and can be used in conventional diesel engines.
The starting material's chemical composition determines the quality and properties of biodiesel. Biodiesel from different sources can differ in its fatty acid composition. ELSD can provide compositional information in a single chromatogram, determining the quality and properties of biodiesel.
Polymer Laboratories is based in Church Stretton, Shropshire, UK. www.polymerlabs.com
