ROS dependent antitumour activity of photo-activated iron(III) complexes of amino acids

  • S Binita Chanu
  • MD Kausar Raza
  • Samya Banerjee
  • Pooja Rani Mina
  • Dulal Musib
  • Mithun RoyEmail author
Regular Article


Several amino acid-based photo-active monomeric iron(III) complexes of the general formula, \([\hbox {Fe(L)}_{2}]^{-}\), where \(\hbox {L} = \) Schiff base ligands (salisalidene arginine, salicylidenetryptophan, 3,5-di-tert-butyl benzalidine arginine and salicylidene tryptophan) were synthesized, characterized and explored for photo-activated anticancer activity to Chang Liver Cells, HeLa and MCF-7 cells. Complexes exhibited remarkable photo-cytotoxicity with \(\hbox {IC}_{{50}}\) value to the extent of \(0.7\, \upmu \hbox {M}\) to Chang Liver Cells in visible light and there was a 40-fold enhancement in cytotoxicity in comparison to the cytotoxicity in dark. Complexes were non-toxic to MCF-10A (normal cells) in dark and visible light (\(\hbox {IC}_{50 }> 100 \, \upmu \hbox {M}\) in dark; \(\hbox {IC}_{50 }> 80 \, \upmu \hbox {M}\) in visible light) signifying target-specific nature of the anti-tumour activity of the complexes. Increased ROS concentration, as probed by DCFDA assay, in the cancer cells was responsible for apoptotic cell death. Decarboxylation or phenolate-Fe(III) charge transfer of photo-activated iron(III) complexes generating \(^{\bullet }\)OH radicals (ROS) were responsible for the apoptosis. Overall, the tumour-selective photo-activated anticancer activity of the amino acid-based iron(III) complexes have shown a promising aspect in developing iron-based photo-chemotherapeutics as the next generation PDT agents.

Graphical abstract

Monomeric iron(III) complexes are explored for photo-activated antitumour activity. Photodecarboxylation or photo-induced charge transfer of phenolate-\(\hbox {O}{\rightarrow }\hbox {Fe(III)}\) has led to the generation of hydroxyl radicals causing apoptotic cell death.


Iron(III) complexes amino acid photocytotoxicity photo-activation ROS generation 



We thank the National Institute of Technology, Manipur for providing a research facility to carry out the work. We gratefully thank the Board of Research in Nuclear Science (BRNS), Mumbai (37(2)/14/18/2017-BRNS) and Department of Science and Technology (DST) (Women Scientist A Scheme (SR/WOSA/CS-31/2016)), Government of India for providing financial support. We thank Prof. Akhil R. Chakravarty for his help in conducting cytotoxicity studies at IISc Bangalore.

Supplementary material

12039_2018_1584_MOESM1_ESM.pdf (1.5 mb)
Supplementary material 1 (pdf 1580 KB)


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Copyright information

© Indian Academy of Sciences 2019
Corrected publication 2019

Authors and Affiliations

  1. 1.Department of ChemistryNational Institute of Technology ManipurLangol, ImphalIndia
  2. 2.Department of Inorganic and Physical ChemistryIndian Institute of ScienceBangaloreIndia
  3. 3.Department of ChemistryJohn Hopkins UniversityBaltimoreUSA
  4. 4.Department of Molecular BioprospectionCSIR-Central Institute of Medicinal and Aromatic PlantsLucknowIndia

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