Trends in Polymer and Particle Characterization by Microfluidic Field-Flow Fractionation Methods: Science or Business?

Abstract

More than 45 years have passed since the invention of field-flow fractionation (FFF). During this time, several methods and techniques, differing mainly by the nature of the applied field, have been proposed and experimentally implemented. However, only few of them are currently in practical laboratory use. Recent trends of miniaturization of all separation techniques have also been followed in the development of FFF apparatus. The aim of this work is to give an overview of the advances that are important in the practical use of microfluidic FFF techniques. Another aim is a critical evaluation of the crucial characteristics of the most widespread FFF techniques performed in standard-size channels.

Critical Review of Techniques for Food Emulsion Characterization

“…The droplets can be separated under any type of external field that interacts with their physicochemical properties. Based on the nature of the field applied to separate droplets, FFF techniques can be divided into several categories, including flow FFF, sedimentation FFF, and electrical FFF [229].…”

Characteristics of electrical field flow fractionation with chronoamperometry and electrochemical impedance

“…The extrapolated line intersects the real axis at R ct,n + R s − W 2 a C dl,p . From (5) and (6) the frequency dependency in this regime comes only from Warburg impedance terms; thus the linear correlation of Z Re and Z Im is the characteristic of a diffusion-controlled electrode process.…”

“…1. Introduction: Field flow fractionation (FFF) with an external force field has a potential advantage in the separation of particles in different sizes [1][2][3][4][5][6]. FFF had been applied to many fields such as food research, environmental observation, medical diagnostics, and nanoparticle research.…”

Characterization of Diamond Nanoparticles by High-Speed Micro-Thermal Field-Flow Fractionation

“…More detailed theoretical approaches can be found, for example, in [7][8][9][10] and a critical evaluation of the advantages as well as of the drawbacks of different FFF techniques applied in current practice in [11]. Only few fundamental definitions are given here to allow a sufficient understanding of the bases of diamond nanoparticles characterization by this technique.…”

“…and (11) where h i is the height of the fractogram in arbitrary units at the i-th retention ratio value R i corresponding to the particle diameter d i calculated from the calibration equation (9).…”