Di-amino and Di-carboxy dextrans are prepared by proprietary methods that yield a primary amine or carboxyl group at each end of the dextran polymer. The molecular weight profile is essentially unchanged, as determined by analytical size exclusion chromatography. Extensive processing and testing is performed to ensure that nonpolymer reagent is removed. This approach results in a consistent product with minimal lot-to-lot variation. These dextrans are unique to Fina Biosolutions and complement our monofunctionalized dextran polymers.