Polymeric prodrugs, 3. Synthesis, elimination, and whole‐body distribution of 14C‐labelled drug carrier

An alternating copolymer of 1-vinyl-2-pyrrolidone and maleic anhydride, 14C-labelled at the chain end, was synthetized with a mass-average relative molecular mass Mw = 8000. Elimination kinetics and whole-body distribution of the copolymer in its monosodium salt form were studied in mice. Elimination of the copolymer was found to be fairly rapid and practically complete, i.e. 86,7% of it was excreted after 24 h and 95% after 56 h. Specific accumulation of the copolymer was observed in bone tissue and lacrimal gland. No appreciable accumulation occurred in the nervous system, spleen, and bone marrow. The results of elimination kinetics and the autoradiographic whole-body distribution study were in fairly good correlation.