ABSTRACT
Field-flow fractionation (FFF) is a family of chromatographic-like elution techniques in which an external field or gradient, rather than partitioning between phases, causes differential retention. FFF techniques were conceived and developed by Professor J. Calvin Giddings starting in 1965, and the theory was first published in 1968 [1]. The method has now become a powerful means for the separation of polymers, colloids, and particles from a wide variety of fields, ranging from medicine to fabrication to environmental studies. For example, FFF has been successfully used for the separation of a variety of biological materials spanning a broad molecular weight and diameter range including proteins [2], protein aggregates [3-6], protein polymer conjugates [7], lipoproteins [8], DNA [4,5,9], viruses [5,10,11], bacteria [3,12], and cells [13]. Also, FFF has been shown to be suitable for the separation of polymers and for the determination of the size distribution of polymer systems [14-16]. For other applications the reader is referred to a special issue on FFF of the Journal of Liquid Chromatography and Related Technology [17] honoring Professor Giddings.
