QUANTITATIVE APPROACH TO FIELD-FLOW FRACTIONATION FOR THE CHARACTERIZATION OF SUPERMICRON PARTICLES

Field-flow fractionation is a separation technique for macromolecular species; over more than 2 decades, it has been studied mostly for enha ncing its separation capabilities in terms of wider applicability, imp roved selectivity, and reduced analysis time. Most of the efforts have been focused on qualitative aspects of fractionation, while the quant itative aspects have been scarcely exploited. However, a quantitative approach to field-flow fractionation is an unavoidable task in the fra mework of a general optimization of this technique, particularly when preparative applications are sought. In this work, an overview of quan titative aspects of gravitational field-flow fractionation for the ana lysis of supermicron particles is presented. In particular, a derivati on of the Lambert-Beer law for flow-through measurements is applied to real-time conversion of the detector signal response into sample mass or concentration. In the proposed approach, particle size distributio n curves are numerically related to sample mass and to the level of sa mple recovery derived together from a single fractionation. (C) 1997 J ohn Wiley & Sons, Inc.