Ai. Hopia et Vm. Ollilainen, COMPARISON OF THE EVAPORATIVE LIGHT-SCATTERING DETECTOR (ELSD) AND REFRACTIVE-INDEX DETECTOR (RID) IN LIPID ANALYSIS, Journal of liquid chromatography, 16(12), 1993, pp. 2469-2482
The properties of an evaporative light scattering detector (ELSD) and
a refractive index detector (RID) in isocratic HPLC analysis of lipids
are compared. The effect of molecular structure, especially the unsat
uration level, on the detector response is studied using eight differe
nt lipid standards. Linearity and sensitivity are compared. Quantitati
on of an unknown sample is also performed. The sensitivity of the ELSD
was slightly better than that of the RID, the detector limits of trio
lein being 30 ng/injection and 50 ng/injection, respectively. The line
arity of the ELSD was considered only approximate compared with that o
f the RID the response factors of the calibration curves being 0.9554
and 0.9999, respectively. The effect of the molecular structure on the
detector response was higher with the RID than with the ELSD. The rel
ative standard deviation (SD%) of responses was 23% for the RID and 12
% for the ELSD. The unsaturation level had a greater effect on the det
ector response of the RID than on that of the ELSD. This study indicat
es that a standard deviation (SD) of at least 13% is to be expected wi
th the ELSD and an even higher SD with the RI detector when quantitati
ng heterogeneous mixtures or unknown compounds.