Kinetics of liposome-encapsulated hemoglobin after 25% hypovolemic exchange transfusion

V. D. Awasthi, D. Garcia, R. Klipper, W. T. Phillips, B. A. Goins

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


Liposome-encapsulated hemoglobin (LEH) is being developed as an oxygen therapeutic. In this work, we evaluated a neutral formulation of PEGylated LEH for its circulation and distribution properties in rodent models of 25% hypovolemic exchange transfusion. About 25% of blood in rats and rabbits was exchanged with LEH that had been previously labeled with 99mTc radionuclide. The distribution of 99mTc-LEH was followed by gamma camera imaging and intermittent blood sampling during 48 h, and counting the tissue-associated radioactivity after necropsy at 48 h. On the basis of circulation kinetics, the half-life of 99mTc-LEH in blood was 30 and 39.8 h in rats and rabbits, respectively. Apart from blood, major organs of accumulation of LEH after 48 h included liver (rats, 10.3% and rabbits, 5.4% of injected dose) and spleen (rats, 2.4% and rabbits, 0.8% of injected dose). The results demonstrate that LEH circulates for a prolonged time after administration and that the animals tolerate at least 25% of blood exchange without any distress. Subsequent to the enhanced uptake in the RES, the rats clear LEH from the circulation faster than the rabbits.

Original languageEnglish (US)
Pages (from-to)53-62
Number of pages10
JournalInternational Journal of Pharmaceutics
Issue number1-2
StatePublished - Sep 28 2004


  • Blood substitute
  • Exchange transfusion
  • Liposome-encapsulated hemoglobin
  • Liposomes

ASJC Scopus subject areas

  • Pharmaceutical Science


Dive into the research topics of 'Kinetics of liposome-encapsulated hemoglobin after 25% hypovolemic exchange transfusion'. Together they form a unique fingerprint.

Cite this