Joachim B. Kohn

Biocompatibility of medical implant materials, artificial biopolymers.

The central hypothesis of our work is that the study of specific biological responses induced by carefully designed and characterized polymers will lead to new insights into the complicated interactions between living tissue and a artificial implant. Thus, our long-term goals are to contribute to a better understanding of the biocompatibility of medical implant materials and to use the knowledge gained to develop optimized polymeric implant materials for a wide range of medical applications. The design, synthesis, and characterization of ÒpseudoÓ-poly(amino acids) represents a specific example of our approach. These materials are new, amino acid derived, degradable polymers in which individual amino acids are linked by non-amide bonds. Among the pseudo-poly(amino acids), we identified a number of new polymers that exhibited good engineering and physico-mechanical properties, as well as high degree of tissue compatibility. After completion of initial evaluations and exploring the effect of surface properties on the attachment and growth of various cell lines, we are now developing specific "pseudo"-poly(amino acids) for implantable drug carriers for the treatment of fibrotic lung diseases. Future research work will relate to tissue engineering and the design of "hybrid" materials that contain artificial and living components.

Recent Publications Nathan, A. and Kohn, J. (1994). Amino acid derived polymers, in: Designed to Degrade Biomedical Polymer. S. W. Shalaby, [ed.]. Hanser Publishers, NY 117-151 Fiordeliso, J., Bron, S., Kohn, J. (1994). Design, synthesis, and preliminary characterization of tyrosin-containing polyarylates: New biomaterials for medical applications, J. Biomater. Sci. 5: 497-510. Parkinson, G.N., Fan, P., Wu, Y., Kohn, J., Baum, J., Berman, H. (1994). Crystal structure and NMR conformation of a cyclic pseudotetrapeptide containing urethane backbone linkages, Biopolymers 34:403-414. Vyavahare, N. and Kohn, J. (1994). Photocrosslinked hydrogels based on copolymers of poly(ethylene glycol) and Lysine, J. Polym. Sci. Part A: Polym. Chem. 32: 1271-1281. Nathan, A., Zalipsky, S., Kohn, J. (1994). Strategies for covalent attachment of dexorubicin to poly(PEG-Lys), a new water-soluble poly(ether urethane), J. Biocat. Compat. Polym. 9: 239-251.