Effects of sequential reagent addition on technetium-99m red blood cell labeling efficiency using the UltraTag kit

J Nucl Med Technol. 1997 Dec;25(4):269-71.


Objective: The purpose of this study was to investigate how the reagent-adding sequence affects 99mTc red blood cell (RBC) labeling efficiency using the UltraTag RBC kit.

Methods: The package insert for preparation and quality control was followed during the experiment. The reagent-adding sequences were then altered during preparation.

Results: If acid-citrate dextrose is added before the NaOCl, the labeling efficiency decreases dramatically. However, the order of addition of Na 99mTcO4 and acid-citrate dextrose did not affect the labeling efficiency.

Conclusion: Addition of the NaOCl solution before the acid-citrate dextrose solution is imperative for proper labeling efficiency.

MeSH terms

  • Erythrocytes
  • Humans
  • Isotope Labeling
  • Reagent Kits, Diagnostic*
  • Technetium*


  • Reagent Kits, Diagnostic
  • Technetium