BIOFUNCTIONAL POLYSTYRENE DERIVATIVES EXHIBIT A HIGH-AFFINITY FOR THEEPIDERMAL GROWTH FACTOR-RECEPTOR (EGF-R) .1.

Insoluble sulfamide of amino acid polystyrene derivatives interact wit h solubilized epidermal growth factor receptor (EGF-R). The choice of the different amino acids substituted on the polystyrene macromolecula r chain is governed by the nature of the peptide involved in the bindi ng of EGF on its receptor. This binding has a hydrophobic character wi th two affinity constants for EGF-R. Some of the amino acids involved in this fixation are known: Leu 44, Tyr 29, Leu 26, Ileu 23, Tyr 22, V al 19, Met 21. Therefore, statistic biofunctional polystyrene derivati ves were synthesized with variable deg rees of substitution by leucine and/or benzylamine or tyrosine. The random substitution may lead to c omplex sites that would interact with EGF-R like EGF. Indeed, among th e studied copolymers, sulfamide of leucine (15% and 44% or tyrosine (3 5%) polystyrene derivatives exhibit a strong affinity for high and/or low affinity solubilized EGF-R and could be held as EGF-like polymers (affinity constants ranging from 2 x 10(9) to 2 x 10(11) M(-1)).