MACROMOLECULAR PRODRUGS .7. POLYMER-DOPAMINE CONJUGATES

Dopamine (3,4-dihydroxyphenetylamine, DOP) was covalently linked to po ly[alpha,beta-(N-2-hydroxyethyl-DL-aspartamide)] (PHEA) and styrene-ma leic anhydride copolymer (SMA) in order to prepare polymeric prodrugs as a potentially more stable form of dopamine. Release of active subst ance from polymer drug conjugates was studied in different buffer solu tions at 37 +/- 0.1 degrees C. The following rate constants for PHEA-D OP were obtained: k = 2.50 x 10(-2) min(-1) (pH = 1.2); k = 4.09 x 10( -3) min(-1) (pH = 7.4), and k = 1.71 x 10(-2) min(-1) (pH = 9.2). The rate constants for SMA-DOP were: k = 2.27 x 10(-3) min(-1) (pH = 7.4) and k = 7.98 x 10(-3) min(-1) (pH = 9.2).