Structure of carbohydrate-bound polynuclear iron oxyhydroxide nanoparticles in parenteral formulations

Dina S. Kudasheva, Jriuan Lai, Abraham Ulman, Mary K. Cowman

Research output: Contribution to journalArticlepeer-review

75 Scopus citations


Intravenous iron therapy is used to treat anemia associated with chronic kidney disease. The chemical structures of parenteral iron agents have not been characterized in detail, and correlations between structure, efficiency of iron delivery, and toxicity via catalysis of oxygen-derived free radical creation remain to be established. In this study, two formulations of parenteral iron have been characterized by absorption spectroscopy, X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), and elemental analysis. The samples studied were Venofer® (Iron Sucrose Injection, USP) and Ferrlecit® (Sodium Ferric Gluconate in Sucrose Injection). The 250-800-nm absorption spectra and the XRD patterns showed that both formulations contain a mineral core composed of iron oxyhydroxide in the β-FeOOH mineral polymorph known as akaganeite. This was further confirmed for each formulation by imaging using TEM and AFM. The average core size for the nanoparticles, after dialysis to remove unbound or loosely bound carbohydrate, was approximately 3 ± 2 nm for the iron-sucrose, and approximately 2 ± 1 nm for the iron-gluconate. Each of the nanoparticles consists of a mineral core, surrounded by a layer of bound carbohydrate. The overall diameter of the average bead in the dialyzed preparations was approximately 7 ± 4 nm for the iron-sucrose, and 3 ± 1 nm for the iron-gluconate. Undialyzed preparations have particles with larger average sizes, depending on the extent of dilution of unbound and loosely bound carbohydrate. At a dilution corresponding to a final Fe concentration of 5 mg/mL, the average particle diameter in the iron-sucrose formulation was approximately 22 ± 9 nm, whereas that of the iron-gluconate formulation was approximately 12 ± 5 nm.

Original languageEnglish
Pages (from-to)1757-1769
Number of pages13
JournalJournal of Inorganic Biochemistry
Issue number11
StatePublished - Nov 2004
Externally publishedYes

Bibliographical note

Funding Information:
This research was supported by American Regent, Inc. A. Ulman and J.L. acknowledge the support from the NSF Garcia MRSEC for Polymers at Engineered Interfaces.


  • AFM
  • Akaganeite
  • Iron oxyhydroxide
  • Iron-carbohydrate complex
  • Iron-sucrose injection
  • Parenteral formulations
  • Sodium ferric gluconate


Dive into the research topics of 'Structure of carbohydrate-bound polynuclear iron oxyhydroxide nanoparticles in parenteral formulations'. Together they form a unique fingerprint.

Cite this