DEFEROXAMINE, A PROMISING BIFUNCTIONAL CHELATING AGENT FOR LABELING PROTEINS WITH GALLIUM - GA-67 DF-HSA - CONCISE COMMUNICATION

  • 1 January 1982
    • journal article
    • research article
    • Vol. 23  (10) , 909-914
Abstract
A new efficient method was developed for the labeling of various biologically important proteins with radiogallium, using deferoxamine (DF) as a bifunctional chelating agent. Human serum albumin (HSA) was chosen for studying the DF coupling reaction by a glutaraldehyde 2-step method. The DF-HSA conjugate obtained was then easily labeled with 67Ga with high efficiency and reproducibility. High stability of 67Ga DF-HSA was observed both in vitro and in vivo. In rates the half-time of blood clearance at the 1st phase was 234 min for the 67Ga DF-HSA, whereas most conventional 131I HSA gives 121 min. The excellent pharmacological and physiological properties were assessed by plasma clearance and plasma volume measurements in normal volunteers. Even at 2 h after injection, 90.0 .+-. 3.0% of 67Ga DF-HSA was retained within the vascular space. The mean plasma vol/kg body wt, measured with 67Ga DF-HSA, was 46.6 .+-. 3.4 ml/kg, compared with 52.2 .+-. 2.4 ml/kg as determind with 131I HSA in the same men.