Arsenic trioxide versus tetraarsenic oxide in biomedical research: misunderstandings and misinterpretations

Biometals. 2012 Feb;25(1):231-5. doi: 10.1007/s10534-011-9489-3. Epub 2011 Aug 28.


This work presents an analytical chemist's view on the sometimes unconscious use of arsenic trioxide in (bio)medical research. Arsenic trioxide is a frequently used chemical in cancer treatment research and its action to various malignant cells has been extensively studied and published. Unfortunately some research articles show trivial errors with regards to background knowledge of the chemical, handling the chemical, experimental design and interpretation of results like e.g. in a range of articles comparing advantages of tetraarsenic oxide over arsenic trioxide (dimeric/monomeric) although the dissolution of both yields the same active compound (HAsO(2)). To fully understand the implications of these errors we will highlight some of them with the intent to harmonize future work in this field.

MeSH terms

  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / metabolism
  • Antineoplastic Agents / therapeutic use
  • Arsenic Trioxide
  • Arsenicals* / chemistry
  • Arsenicals* / metabolism
  • Arsenicals* / therapeutic use
  • Biomedical Research*
  • Humans
  • Oxidation-Reduction
  • Oxides* / chemistry
  • Oxides* / metabolism
  • Oxides* / therapeutic use
  • Tumor Cells, Cultured


  • Antineoplastic Agents
  • Arsenicals
  • Oxides
  • Arsenic Trioxide