Abstract: A hyperbranched amidoamine polymer comprising [A] a first structural repeating unit having a connectivity of three consisting of a nitrogen core linked to a first amidoamine unit, a second amidoamine unit and a third amidoamine unit, [B] a second structural repeating unit having a connectivity of two consisting of a nitrogen core linked to a first amidoamine unit and a second amidoamine unit and [C] terminal units of which a major portion comprises amine groups or a functional derivative thereof, and a minor portion comprises carboxylic acid or related groups or a functional derivative thereof.

Abstract: A water-soluble hyperbranched polymer comprising a porphyrin moiety and one or more hyperbranched polymer chains covalently bound thereto. The polymer when metalated with an Fe(II) ion is capable of mimicking the oxygen binding properties of blood. The polymer may be used as a haemoglobin replacement, in synthetic blood products and as a blood substitute.