Single-injection calibration approach for high-performance liquid chromatography.
A new calibration method for high-performance liquid chromatography was validated. The method was called single-injection calibration approach (SICA) because it allowed to obtain a complete calibration curve by means of a single injection of a standard solution containing several non-volatile and semi-volatile organic compounds at different concentration levels. The compounds studied included carboxylic acids, polyalcohols, carbohydrates and water-soluble vitamins. This method allowed a 1-7-fold reduction in the analysis time with regard to conventional calibration methods. The method was applied to three different chromatographic detection methods: refractive index (RI) detection, diode array detection (DAD) and inductively coupled plasma atomic emission detection (ICP-AED). Good linearity was achieved (r(2)>0.999) for the three detection methods but signal correction was required for RI detection and DAD. This fact demonstrated that ICP-AES was the most universal because the signal obtained for non-volatile and semi-volatile organic compounds was not a function of the chemical nature of the compound and only depended on the mass content of carbon. The method was validated by analyzing a reference non-fat milk powder sample as well as several real food samples (three fruit juices, four wines, three candies and a multivitamin complex).
Paredes
Eduardo
E
Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, 03080 Alicante, Spain.
Maestre
Salvador E
SE
Prats
Ma Soledad
MS
Todolí
José L
JL
D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005504:Food Analysis / Q000379:methods*; D009930:Organic Chemicals / Q000032:analysis*
D009930:Organic Chemicals