Ficoll 400: Ficoll 400 is a highly branched polymer formed by the copolymerization of sucrose and epichlorohydrin. Ficoll 400 is completely non-ionic. Because of the abundance of hydroxyl groups, Ficoll 400 is very hydrophilic and extremely water-soluble. The most common application for Ficoll 400 is as a density gradient medium for the separation and isolation of eukaryotic cells, organelles, and bacterial cells. Density ranges up to 1.2 g/ml can be attained. It has also been utilized in a variety of other applications.