SOLUBLE POLYMERIC CARRIERS FOR DRUG DELIVERY .1. FREE-RADICAL COPOLYMERIZATION OF N-(2-HYDROXYPROPYL)METHACRYLAMIDE WITH N-[2-(4-HYDROXYPHENYL)ETHYL]ACRYLAMIDE

N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers have been described in the literature as soluble drug carriers. The fate of such polymers in biological systems is conveniently examined using radioactively labeled polymers. We describe the preparation of a new copolymer of HPMA (I) with N-[2-(4-hydroxyphenyl)ethyl]acrylamide (II) (HPEA). We have determined the mutual reactivity of HPMA and HPEA using gas chromatographic analysis of the polymerizing mixture, and calculated the copolymerization parameters r1 and r2, using the Kelen-Tudos equation. Radioiodination of the copolymer with Na125I in the presence of chloramine T has been found to be facile, and the stability of the label has been assessed using gel permeation chromatography.