Quantitative analysis without analyte identification by refractive index detection

Contrary to the accepted notion that qualitative analysis must precede quantitative analysis, the authors show that one can determine the volume fraction of an arbitrary analyte in a flowing system without knowing its identity. The physical and chemical properties of the analyte are thus unknown, and no working curve can be established. The scheme is based on the refractive index detector, which produces two distinct responses for the same analyte when two separate eluents are used. The information obtained can be used to predict the volume fraction of the analyte, as well as its refractive index. Experimental verification of this scheme is reported. 1 figure, 2 tables.