Synthesis and application of lactosylated, 99mTc chelating albumin for measurement of liver function.

Neogalactosylated and neolactosylated albumins are currently used as radiopharmaceutical agents for imaging the liver asialoglycoprotein receptors, which allows the quantification of hepatic liver function in various diseases and also in healthy liver transplant donors. We developed an original process for synthesizing a chelating neolactosylated human albumin using maleimidopropyl-lactose and maleimidopropyl-diethylene triamine pentaacetic acid (DTPA) derivatives. The lactosylated protein (LACTAL) conjugate showed excellent liver uptake compared to nonlactosylated protein and a very high signal-to-noise ratio, based on functional assessment of biodistribution in mice using (99m)Tc-scintigraphy.