In Vivo Fate of End-Chain Radiolabelled Poly(β-malic acid), a Water-Soluble Biodegradable Drug Carrier

• Published in: Journal of bioactive and compatible polymers 1990-10, Vol.5 (4), p.381-395
• Main Authors: Fournie, Philippe, Domurado, Dominique, Guerin, Philippe, Braud, Christian, Vert, Michel, Madelmont, Jean-Claude
• Format: Article
• Language: English
• Subjects: Antibacterial agents; Antibiotics. Antiinfectious agents. Antiparasitic agents; Biological and medical sciences; Medical sciences; Pharmacology. Drug treatments
• ISSN: 0883-9115; 1530-8030
• DOI: 10.1177/088391159000500401

In a first attempt to determine the fate of poly(β-malic acid) after intravenous injection in mice, polymer end-chain 14C-radiolabelling was achieved using 14C-triethylamine as the initiator for the ring-opening polymer ization of benzyl malolactonate. The corresponding poly(β-malic acid) sodium salt (Mw ∼ 30,000) exhibited an activity of 4.2 μCi :g-1. Aliquots of a neutral isoosmotic solution of the latter were given intravenously to mice through a lateral tail vein. Radioactivity was counted in the liver, kidney, intestine, lung, brain, spleen, heart, muscle, urine and blood for various post-injection times up to 24 hours. Fast urinary excretion (70% after 1 hour and 90% after 6 hours) was observed. For all the sites investigated, radioactivity decreased exponen tially except in the liver and kidneys where a small peak was detected after 2 hours. Further investigations with poly(β-malic acid) radiolabelled in repeat ing units will be necessary to overcome the shortcomings of the end-chain radiolabelling method applied to degradable polymers.