Since their introduction by Kohn and Langer et al. in 1984, L-tyrosine based 'pseudo' poly(amino acids) have undergone extensive research in the area of polymeric biomaterials. Starting from L-tyrosine based diphenolic monomers, polyiminocarbonates, polycarbonates and polyarylates have been developed by Kohn and co-workers and are being investigated for potential orthopedic biomaterial applications. Mao et al. have reported development Of L-tyrosine based polyphosphates and polyphosphonates in a patent, however, detailed structural and physico-chemical characterization studies on such polymers have not been reported yet. For the purpose of the current paper, using a novel solid phase process for synthesis Of L-tyrosine based diphenolic monomers and adapting the polymerization process described by Mao et al., L-tyrosine based polyphosphates were developed and investigated for their pertinent bioengineering properties. The properties investigated consist of chemical solubility, hydrophilicity and hydrolytic degradation. The results of this investigation are crucial to validate further investigation of biomaterial applications of these polymers. (c) 2005 Published by Elsevier Ltd.