The invention provides a non-particulate cross-linked poly-ε-lysine polymer. The poly-ε-lysine and cross linker are linked by amide bonds and may the cross linker has at least two functional groups capable of reacting with an alpha carbon amine of poly-ε-lysine. The polymer is suitably insoluble in water and other solvents and is provided in macro form for example a sheet, article or fibre. The macro form polymer is useful in a wide range of applications including wound treatment, as a medical diagnostic comprising a particulate support and a functional material bound or retained by the support and solid phase synthesis of peptides, oligonucleotides, oligosaccharides, immobilisation of species, cell culturing and in chromatographic separation.
