Development of a dual-sensing colorimetric probe for total antioxidant capacity measurement using iron(III)-o-phenanthroline reagent

ELMAS E., ŞEN F. B., BENER M., APAK M. R.

TALANTA, cilt.288, 2025 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 288
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.talanta.2025.127751
  • Dergi Adı: TALANTA
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, L'Année philologique, Aerospace Database, Analytical Abstracts, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Food Science & Technology Abstracts, Metadex, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Anahtar Kelimeler: Colorimetric, Dual-mode sensing, Fe(III)-o-phenanthroline reagent, Food extracts, Total antioxidant capacity
  • İstanbul Üniversitesi Adresli: Evet

Özet

In this study, a dual-mode sensing system was developed for the determination of total antioxidant capacity (TAC) using the Fe(III)-phenanthroline (Fe(III)-phen) reagent. The first detection mechanism of the system is based on the reduction of the Fe(III)-phen reagent by antioxidants, leading to the formation of the orange-red Fe (II)-phen chelate, which is quantified by the absorbance change at 510 nm. The second mechanism exploits the oxidase-like activity of the Fe(III)-phen complex. This complex generates superoxide anion radicals that oxidize 3,3 ',5,5 '-tetramethylbenzidine (TMB) to produce a blue-colored oxidized TMB (ox-TMB) charge-transfer complex. In the presence of antioxidants, this reaction is inhibited, resulting in a decrease in ox-TMB formation, and the absorbance change at 652 nm correlates with the TAC of the tested sample. The proposed system was successfully applied to standard antioxidants, synthetic antioxidant mixtures, and real food extracts, demonstrating its applicability and sensitivity for TAC analysis. The linear equation of the calibration graphs obtained for different trolox (TR) concentrations were found to be A510 = 0.0221CTR + 0.0223 (A: absorbance and C: concentration in mu M) and LA = 0.0301CTR + 0.0583 (LA: the difference of absorbance resulting from decreasing ox-TMB formation in the presence of TR, and C: concentration in mu M) for the reduction-based Fe(III)-phen method and the TMB-based Fe(III)-phen method, respectively. The limits of detection (LOD) for the reduction based Fe(III)-phen method and the TMB-based Fe(III)-phen method were found to be 0.45 and 0.87 mu M, respectively, for trolox. The LOD was calculated using the equation; LOD = 3 sbl/m (sbl: standard deviation of a blank, m: slope of the calibration line). This study presents an innovative approach by utilizing the same probe, Fe(III)-phen, through two distinct mechanisms for the simple, rapid, and sensitive determination of TAC.