Experience with Technetium-99m Albumin Colloid Kit for Reticuloendothelial System Imaging

Abstract

The ^99mTc labeled albumin colloid has been evaluated regarding its particle size, both in vitro and in vivo stability, blood clearance, and efficacy in reticuloendothelial system imaging. The labeling efficiency was always > 99%. The labeled colloid remained stable both in vitro and in vivo for up to 24 hr. The blood clearance curve from four patients had two components: one with a T_½ of 2.48 ± 0.37 min and the other with a T_½ of 271 ± 109 min. Images of the liver, spleen, and bone marrow with ^99mTc-albumin colloid and ^99mTc-sulfur colloid showed a similar distribution pattern except that slightly higher splenic uptake relative to the liver was observed with the former. However, ^99mTc-albumin colloid has the advantage of easy preparation over ^99mTc-sulfur colloid.