Used in molecular biology for transfection of cells, DEAE Dextran enhances the uptake of nucleic acids by binding to cell membranes and promoting endocytosis. Commonly applied in gene expression studies, it facilitates the introduction of DNA or RNA into cultured cells, especially in suspension cells that are hard to transfect with other methods. Also used in chromatography as an ion-exchange medium for protein purification due to its positive charge at neutral pH. Additionally, it finds use in immunology assays to precipitate macromolecules and in drug delivery systems for controlled release of negatively charged therapeutic agents.