Preparation of Tc-99m-macroaggregated albumin from recombinant human albumin for lung perfusion imaging

Hunt, Amelia and Frier, M and Johnson, RA and Berezenko, S and Perkins, AC (2006) Preparation of Tc-99m-macroaggregated albumin from recombinant human albumin for lung perfusion imaging. European Journal of Pharmaceutics and Biopharmaceutics, 62 (1). pp. 26-31. ISSN 0939-6411

Abstract

Human serum albumin (HSA) extracted from pooled blood taken from human donors is used in the production of Tc-99m-labelled macroaggregated albumin (MAA) for lung perfusion imaging. However, concerns for the safety of blood-derived products due to potential contamination by infective agents (e.g. new variant CJD), make alternative production methods necessary. Recombinant DNA technology is a promising method of albumin production avoiding problems associated with human-derived HSA. This paper presents results comparing MAA prepared from recombinant human albumin (MA, Recombumin (R)) (rMAA) with in-house produced HSA MAA (hMAA) and commercially available MAA (cMAA). Tc-99m-MAA was prepared using previously published production methods by heating a mixture of albumin and stannous chloride in acetate buffer (pH 5.4) at 70 degrees C for 20 min. Parameters investigated include aggregate size, radiolabelling efficiency, radiochemical and aggregate stability at 4 degrees C and in vitro (in whole human blood) at 37 degrees C and biodistribution studies. Results showed that rMAA could be produced with similar morphology, labelling efficiency and stability to hMAA and cMAA. Our findings confirm that rHA shows significant potential as a direct replacement for HSA in commercially available MAA. (c) 2005 Elsevier B.V. All rights reserved.