Novel assay for efficient iron release from ferritin

W. F. Lim, M. Abdullah, Boon Kar Yap, E. George, M. I. Lai

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Ferritin plays an important role in iron detoxification and iron storage by converting soluble iron(II) to insoluble iron(III) inside the protein cage. Mechanism of in vitro ferritin iron release occurs more readily under reducing conditions, whereby reducing agents may enter into the ferritin cage through the protein pores to convert insoluble iron(III) into soluble iron(II), after accepting an electron from reducing agents. The soluble iron(II) then liberates outside the protein cage and forms coloured and stable complexes in the presence of chromophore, an iron(II) chelating agent, to be quantified by spectrophotometry. However, iron(II) is readily converted back to iron(III) in the presence of oxygen. Thus, oxygen scavenger compounds were used to remove any dissolved oxygen. Studies suggested that low concentration of chaotropic agents regulate the protein pore opening and result in protein unfolding that is therefore accessible by reducing agents more effectively. According to in vivo studies, iron exit from ferritin for recycling or meeting the cell's need via lysosomal and/or proteasomal pathways. We designed an assay to determine the total iron available inside the ferritin by first using the commercially available iron(II) or iron(III) compounds as a substrate to optimize the concentration of reactants involved. Apart from chromophore and reducing agents, oxygen scavenger compounds, chaotropic agents and enzymes were added in order to induce ferritin iron release effectively. Linear calibration curve of the iron(II)-chromophore complex were obtained and was used as a reference to correlate absorbance readings to concentration of iron level. Reducing agents was able to reduce the iron(III) to iron(II) and oxygen scavenger A seems to be more effective in removing any dissolved oxygen to avoid oxidation of both the reducing agents and iron(III). Taken altogether, this experiment setup will be beneficial for the improvement of efficiency in quantifying the total iron level inside the ferritin.

Original languageEnglish
Title of host publicationIECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences
Subtitle of host publication"Miri, Where Engineering in Medicine and Biology and Humanity Meet"
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages132-136
Number of pages5
ISBN (Electronic)9781479940844
DOIs
Publication statusPublished - 01 Jan 2014
Event3rd IEEE Conference on Biomedical Engineering and Sciences, IECBES 2014 - Kuala Lumpur, Malaysia
Duration: 08 Dec 201410 Dec 2014

Publication series

NameIECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet"

Other

Other3rd IEEE Conference on Biomedical Engineering and Sciences, IECBES 2014
CountryMalaysia
CityKuala Lumpur
Period08/12/1410/12/14

Fingerprint

Assays
Iron
Reducing agents
Proteins
Chromophores
Oxygen
Dissolved oxygen
Iron compounds

All Science Journal Classification (ASJC) codes

  • Biomedical Engineering

Cite this

Lim, W. F., Abdullah, M., Yap, B. K., George, E., & Lai, M. I. (2014). Novel assay for efficient iron release from ferritin. In IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet" (pp. 132-136). [7047471] (IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet"). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/IECBES.2014.7047471
Lim, W. F. ; Abdullah, M. ; Yap, Boon Kar ; George, E. ; Lai, M. I. / Novel assay for efficient iron release from ferritin. IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet". Institute of Electrical and Electronics Engineers Inc., 2014. pp. 132-136 (IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet").
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Lim, WF, Abdullah, M, Yap, BK, George, E & Lai, MI 2014, Novel assay for efficient iron release from ferritin. in IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet"., 7047471, IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet", Institute of Electrical and Electronics Engineers Inc., pp. 132-136, 3rd IEEE Conference on Biomedical Engineering and Sciences, IECBES 2014, Kuala Lumpur, Malaysia, 08/12/14. https://doi.org/10.1109/IECBES.2014.7047471

Novel assay for efficient iron release from ferritin. / Lim, W. F.; Abdullah, M.; Yap, Boon Kar; George, E.; Lai, M. I.

IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet". Institute of Electrical and Electronics Engineers Inc., 2014. p. 132-136 7047471 (IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet").

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Lim WF, Abdullah M, Yap BK, George E, Lai MI. Novel assay for efficient iron release from ferritin. In IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet". Institute of Electrical and Electronics Engineers Inc. 2014. p. 132-136. 7047471. (IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet"). https://doi.org/10.1109/IECBES.2014.7047471