Catalytic effect of cytochrome c on H2O2 oxidation of a p-hydroxyphenyl-substituted BODIPY derivative

Qinhai Xu; Kang Li; Yang Liu; Delong Kong; Peng Wang

doi:10.25259/AJC_938_2025

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Original Article

ARTICLE IN PRESS

doi:

10.25259/AJC_938_2025

Catalytic effect of cytochrome c on H₂O₂ oxidation of a p-hydroxyphenyl-substituted BODIPY derivative

Qinhai Xu^a,*, Kang Li^b, Yang Liu^a, Delong Kong^a, Peng Wang^b

aCollege of Chemistry, Chemical Engineering and Materials Science, Zaozhuang University, Zaozhuang, Shandong Province, China

bSchool of Chemistry and Life Resources, Renmin University of China, Beijing, China

*Corresponding author: E-mail address: 1249661455@qq.com (Q. Xu)

Received: 2025-08-09, Accepted: 2026-01-02, Epub ahead of print: 2026-03-26,

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Abstract

As a peroxidase, cytochrome c (Cyt-c), could catalyze the oxidation of a p-hydroxystyryl-substituted BODIPY derivative (BOH) induced by H₂O₂ through the oxidation of the C=C bond in the p-hydroxystyryl functional group. The stable structure of BOH was calculated that the BODIPY basic structure with a p-hydroxystyryl group which led to the fluorescence emission of BOH was perpendicular to the benzene ring containing a carboxyl group. The compounds containing ferriporphyrin have the catalytic effect on the reaction of BOH + H₂O₂. However, there is no catalytic effect on the reaction of BOH + H₂O₂ of the porphyrin ring without Fe, Fe²⁺ and Fe³⁺. It shows that the coordination between Fe and N (Fe−N coordination) plays a central role in the peroxidase-like catalysis of the oxidation of BOH by H₂O₂. Interestingly, hemoglobin (Hb) and myoglobin (Mb) also act as catalysts for the oxidation of BOH by H₂O₂. However, the catalytic rates of hemoglobin (Hb) or myoglobin (Mb) on H₂O₂ oxidation of BOH are lower compared to those of Cyt-c. This difference in reactivity might be attributed to the use of Cyt-c from horse heart in its reduced form with the five-coordinate structure, and the significant steric hindrance effect resulting from variations in the distribution positions of −CH₂−CH₂−COOH groups and the iron porphyrin rings, as revealed by crystal structure analysis. This study might have practical significance for the p-hydroxystyryl-substituted BODIPY derivative in the application of catalytic oxidation and fluorescence sensing.

Keywords

BODIPY

Catalysis

Cytochrome c

Fe−N coordination

H2O2

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1. Introduction

The derivatives of BODIPY (4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene) have been extensively used as functional fluorescent probes in various fields such as ions, biological labeling, and reactive oxygen species (ROS) due to their exceptional photostability, high molar extinction coefficient, high fluorescence quantum yield, and sharp absorption and emission spectra [1-3]. A large number of BODIPY derivatives have been developed as antioxidant fluorescent probes by extending the π-conjugation of the BODIPY parent material through the p-hydroxystyryl group at the C−3 or C−5 positions of the BODIPY parent substance for the detection of oxidized species [4-7]. Jantra et al. synthesized an orange fluorescent probe based on styryl-BODIPY for the detection of hypochlorite and its application in live cell imaging [4]. Xu et al. discussed the oxidative cleavage of C=C bonds in BODIPY photocages using visible light [6]. Wang et al. developed a novel phenol-based BODIPY chemosensor for the selective detection of Fe³⁺ using colorimetric and fluorometric dual-mode [7]. Among them, the main reason for the spectral changes is believed to be the oxidation effect of ROS on the C=C bond in the styryl groups, which governs the reaction mechanism. More importantly, it is noteworthy that there is currently no p-hydroxystyryl-substituted BODIPY derivative for H₂O₂ sensing due to the absence of a redox reaction between the p-hydroxystyryl group and H₂O₂ [4-8]. As the most stable ROS, H₂O₂ is produced through the dismutation of O₂^•− by superoxide dismutase (SOD) [9]. H₂O₂ could generate ^•OH in the presence of transition metals like iron and copper through the Fenton reaction [10], also produce ClO⁻ with Cl⁻ when catalyzed by the enzyme myeloperoxidase (MPO) in biological processes [11]. Moreover, H₂O₂ serves as an essential intracellular signaling component for proliferation and apoptosis in living organisms [12]. However, the level of H₂O₂ is closely associated with various diseases, including the oxidation of DNA, lipids, and proteins, as well as neurological disorders [12-15]. Given the significance of H₂O₂ in physiological and biochemical processes, it is crucial to discover catalysts that can facilitate the oxidation of p-hydroxystyryl-substituted BODIPY derivative by H₂O₂.

Notably, cytochrome c (Cyt-c) is a highly efficient electron transfer protein that plays a crucial role in the respiratory chain of mitochondria [16-18]. It receives electrons from Cyt-c reductase and delivers them to Cyt-c oxidase. Additionally, Cyt-c, which contains an iron porphyrin, acts as a peroxidase and catalyzes the oxidation of cardiolipin (CL) in the mitochondrial membrane during apoptosis, organic compounds, and protein tyrosines [19-21]. More importantly, the mechanism of Cyt-c catalyzed H₂O₂ oxidation has attracted considerable interest. When H₂O₂ reacts with Fe³⁺ in Cyt-c, it forms a compound known as ‘Compound I’, which consists of a Fe(IV)=O heme and an adjacent radical. Subsequent H abstraction from organic substrates restores the resting state. The R^• radicals formed in this process undergo further transformations to produce the final oxidation products [21,22]. It is noted that the iron porphyrin, with its Fe−N composite structure, plays a critical role in catalyzing the oxidation of substrates by H₂O₂. Therefore, considering the significant role of Cyt-c in catalyzing H₂O₂ oxidation in organisms, studying the p-hydroxystyryl-substituted BODIPY derivative and its related reaction mechanisms in Cyt-c catalyzed H₂O₂ oxidation is of great importance.

In this work, a p-hydroxystyryl-substituted BODIPY fluorescent sensor (BOH) is synthesized to investigate the oxidation of the p-hydroxystyryl group by H₂O₂ under the catalysis of Cyt-c by the absorption spectra and fluorescence spectra (Scheme 1) [23]. The structure of BOH is calculated based on two planar structures in the molecular structure of BOH. One planar structure could include the BODIPY basic structure with a p-hydroxystyryl group. The other planar structure is a benzene ring containing a carboxyl group. The influence of Fe and N coordination on the reaction of BOH + H₂O₂ is also demonstrated by examining heme-containing molecules and artificially synthesized Fe and N complexes. More importantly, two other hemoproteins, myoglobin (Mb) and hemoglobin (Hb) are also utilized as catalysts for the oxidation of BOH by H₂O₂. The crystal structure analysis is conducted to understand the reasons for the different reaction rates of H₂O₂ oxidation of BOH catalyzed by these three hemoproteins. It hoped that BOH as a H₂O₂ fluorescence probe based on Cyt-c catalysis could have potential applications in H₂O₂ oxidative fluorescence imaging.

Catalytic effect of cytochrome c on H2O2 oxidation of a p-hydroxyphenyl-substituted BODIPY derivative (BOH).

2. Materials and Methods

2.1. Reagents and apparatus

Cytochrome c (Cyt-c) from horse heart (main components were the reduced form), myoglobin (Mb) from equine skeletal muscle and hemoglobin (Hb) from bovine blood were bought from Solarbio (Beijing, China). Hematoporphyrin (He), Hemin (Hc), Hematin porcine (Hh), Iron(IIII) Meso-Tetraphenylporphine Chloride (It) were brought from Shanghai Macklin Biochemical CO., Ltd (Shanghai, China).

The UV-Vis absorption spectra were measured using a Cary 60 UV-Vis spectrophotometer (Agilent Technologies, USA). The fluorescent spectra were recorded using a fluorescence spectrophotometer (HITACHI F-4600, Japan). QTOF-MS spectra were obtained using a high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS) system with electron spray ionization (ESI) in the positive mode (waters, Xevo G2 Qtof, USA).

2.2. Synthesis of BOH

A BODIPY derivative (BOD) was synthesized following Safacan Kolemen’s method [24]. As described in the Supporting Information (Section S1.3. Synthesis of BOH), a p-hydroxystyryl-substituted BODIPY derivative (BOH) was synthesized using a BODIPY derivative (BOD) as an organic synthesis raw material in our previous work [25]. The physicochemical parameters of BOH and BOD in ethanol solution were also shown separately in our previous work [25].

Supporting Information

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2.3. The effects of the coordination between Fe and N on the oxidation of BOH by H₂O₂

The effects of Fe²⁺ and Fe³⁺ on the reaction of BOH + H₂O₂ were initially studied. 0.5 mL of Fe²⁺ (1 mM) or 0.5 mL of Fe³⁺ (1 mM) was added into 0.5 mL of BOH (10 μM) and 20 μL of H₂O₂ (10 mM), respectively.

The effects of heme on the reaction of BOH + H₂O₂ were explored by the use of four compounds. Hematoporphyrin (He), Hemin (Hc), Hematin porcine (Hh) and Iron(IIII) Meso-Tetraphenylporphine chloride (It) were selected to investigate their catalytic effects on the oxidation of BOH by H₂O₂. 20 μL of Hematoporphyrin (He), Hemin (Hc), Hematin porcine (Hh), or Iron(IIII) Meso-Tetraphenylporphine Chloride (It) (1 mM) were added into 1 mL of BOH (5 μM) and 0.5 mL of H₂O₂ (10 mM), respectively.

The catalytic of Fe³⁺ with 1,10-phenanthroline (o-phen) and Fe³⁺ with 2,2’-Bipyridine complexes on BOH + H₂O₂ were finally studied. 1 mL of o-phen or 2,2’-Bipyridine ethanol solutions were added into 1 mL of Fe³⁺ (1 mM), separately. The two mixed solutions turned orange, indicating the formation of iron complex [26-28]. Then 1 mL of BOH and 50 μL of H₂O₂ (10 mM) were added into the two complex solutions, respectively. The absorption spectra of each sample were continuously measured for 18 times over a duration of 204 s using a Cary 60 UV-Vis spectrophotometer.

2.4. The catalysis of hemoproteins on the oxidation of BOH by H₂O₂

Hemoproteins including cytochrome c (Cyt-c), myoglobin (Mb) and hemoglobin (Hb) solutions (10 μM) were dissolved in deionized water, respectively. 1 mL of BOH (10 μM) and 100 μL of H₂O₂ (0.01 M) were added to 0.5 mL of the three proteins solutions, respectively. The absorption spectra of the mixed solutions were then measured 10 times over a period of 108 s using a Cary 60 UV-Vis spectrophotometer.

3. Results and Discussion

3.1. The optimized molecular structure of BOH

The optimized molecular structure of BOH was obtained from the DFT-based theoretical calculations at the B3LYP (6-31G (d, p)) level using the Gaussian09 package. There were two planar structures in the molecular structure of BOH. One planar structure included the BODIPY basic structure with a p-hydroxystyryl group. The other planar structure was a benzene ring containing a carboxyl group shown in Figure 1(a) Inserts: (Ⅰ). The total energy scans was calculated for BOH as a function of the dihedral angles in Figure 1(a). The most stable structure of BOH was observed at dihedral angles of 90 and 270 degrees [25]. Therefore, the dipyrrolic plane was perpendicular to the meso-substituted phenyl group, while the p-hydroxystyryl group and the dipyrrolic group were coplanar in BOH, as displayed in Figure 1(a) Inserts: (Ⅱ), consequentially resulting in the significant extension of conjugation systems in BOH compared with the BODIPY basic structure. It was inferred that the BODIPY basic structure with a p-hydroxystyryl group was related to the fluorescence emission of BOH, while the benzene ring containing a carboxyl group could not contribute to the fluorescence emission. The fluorescence emission spectrum (experimental) and the calculated fluorescence emission spectrum of BOH (calculated) were shown in Figure 1(b). The calculated fluorescence emission peak and the experimental fluorescence emission peak of BOH was located at 530 and 589 nm, respectively. The calculated fluorescence emission peak showed a hypsochromic shift compared to the experimental fluorescence peak, which might be attributed to the dynamic effects and the solvent relaxation effects [29]. Frontier molecular orbital distributions were used to evaluate the hole and electron transport properties of BOH in Figure 1(c) [30]. The highest occupied molecular orbital (HOMO) distribution of BOH was localized in the BODIPY basic structure with a p-hydroxystyryl group in the BOH molecular structure. The lowest unoccupied molecular orbital (LUMO) distribution of BOH was predominantly concentrated within the BODIPY basic structure in the BOH molecular structure. It was also indicated that the fluorescence emission of BOH was attributed to the BODIPY basic structure with a p-hydroxystyryl group in the BOH molecular structure. Accordingly, the stable structure of BOH was that the BODIPY basic structure with a p-hydroxystyryl group which led to the fluorescence emission of BOH was perpendicular to the benzene ring containing a carboxyl group.

(a) The total energy scans depend on the dihedral angles for BOH obtained from the DFT-based theoretical calculations at the B3LYP (6-31G (d, p)) level using the Gaussian09 package. (Inserts: (Ⅰ) Molecular structure of BOH, (Ⅱ) Optimized molecular structure of BOH obtained from the DFT-based theoretical calculations at the B3LYP (6-31G (d, p)) level using the Gaussian09 package [25]. (b) The fluorescence emission spectrum (experimental) and the calculated fluorescence emission spectrum (calculated) of BOH obtained from the DFT-based theoretical calculations at the B3LYP (6-31G (d, p)) level using the Gaussian16 package. (c) Frontier molecular orbitals of BOH obtained from the DFT-based theoretical calculations at the B3LYP (6-31G (d, p)) level using the Gaussian16 package.

3.2. The catalysis of Cyt-c in the oxidation of BOH by H₂O₂

The catalytic effect of cytochrome c (Cyt-c) in the oxidation of BOH by H₂O₂ was investigated using spectroscopic analysis. There were no changes in the UV-Vis absorption and fluorescence emission spectra of BOH and BOH + H₂O₂, which emitted bright orange fluorescence in Figure 2(a). This indicated that there was no redox reaction between BOH and H₂O₂. Consistent with previous literature reports [4,8], H₂O₂ had no effect on the p-hydroxystyryl-substituted group. However, it is interesting to note that Cyt-c, acting as a peroxidase, could catalyze the H₂O₂-induced oxidation of organic substrates [20-22]. Therefore, Cyt-c was chosen to catalyze the reaction between BOH and H₂O₂. It was observed that the redox reaction of BOH, Cyt-c, and H₂O₂ occurred rapidly upon addition of Cyt-c to BOH + H₂O₂, resulting in bright green fluorescence. As shown in Figures 2(b and c), A new absorption peak at 503 nm, and a new fluorescence peak at 518 nm of new products were observed, which were similar to that of BOD with a absorption peak at 499 nm and a fluorescence peak at 509 nm. Compared to the spectra of BOH, the absorption and fluorescence emission spectra of the new products exhibited a blue shift. This suggested that the conjugated carbon chains of the new products were shorter than those of BOH, similar to those of BOD. Therefore, it could be inferred that the chemical structures of the new species were likely to be similar to that of BOD. Accordingly, the new products generated by the oxidation of BOH by H₂O₂ under the catalysis of Cyt-c were further characterized using LC-QTOF-MS. The results of the reaction of BOH and Cyt-c + H₂O₂ showed that the molecular weight of the new products were 503.1983 and 517.2115. By analyzing the changes in the absorption and fluorescence emission spectra, the structural formulas of the new products were proposed, which could be described as 1h and 2h in Scheme 2 [4,31]. The C=C double bond in the p-hydroxystyryl functional group was oxidized to a C−C single bond. The conjugated carbon chain of the proposed structural formulas were shorter than that of BOH, which was similar to that of BOD. The proposed molecular formula is reasonable. Therefore, these results indicated that the catalysis of Cyt-c in the oxidation of BOH by H₂O₂ primarily occurred at the C=C bond in the p-hydroxystyryl functional group.

(a) The fluorescent image, (b) The absorption spectra and (c) The fluorescence emission spectra of BOH, BOH + Cyt-c, BOH + H2O2, and BOH + Cyt-c + H2O2, λEx = 365 nm.

The proposed products and intermediates from reactions between BOH and Cyt-c + H2O2 characterized by LC-QTOF-MS.

3.3. Effect of the coordination between Fe and N in the reaction of BOH + H₂O₂

Due to the iron porphyrin as the prosthetic group in Cyt-c as a peroxidase that catalyzing the H₂O₂-induced oxidation, the coordination interaction of Fe with N in the iron porphyrin on Cyt-c catalyzed H₂O₂ oxidation of BOH was studied through the absorption spectra. As shown in Supplementary materials Figure S1, Fe²⁺, Fe³⁺, Hematoporphyrin (He), Hemin (Hc), Hematin porcine (Hh) and Iron(IIII) Meso-Tetraphenylporphine chloride (It) were selected to investigate their catalytic effects on the oxidation of BOH by H₂O₂. The absorption spectra had no change when Fe²⁺ or Fe³⁺ were added into BOH + H₂O₂ in Figures 3(a and b), showing that Fe²⁺ and Fe³⁺ had no effect on BOH + H₂O₂. It might be attributed to the reactions between Fe²⁺ or Fe³⁺ and H₂O₂, which leaded to the inability to oxidize BOH. Fe³⁺ could catalyze the decomposition of H₂O₂ (Step 1: 2Fe³⁺ + H₂O₂ = 2Fe²⁺ + O₂ ↑+ 2H⁺, Step 2: 2Fe²⁺ + H₂O₂ + 2H⁺ = 2Fe³⁺ + 2H₂O, Total reaction: 2H₂O₂ = 2H₂O + O₂ ↑). The Fenton reaction occured between Fe²⁺ and H₂O₂ to produce ^•OH (Fe²⁺ + H₂O₂ → Fe³⁺ + OH⁻ + ^•OH). It also showed that ^•OH had no influence on the p-hydroxystyryl group of BOH, which was consistent with the result of the literature [4]. It might be due to the fact that the short lifetime of ^•OH (10^-9 s) could not allow for sufficient molecular diffusion and reaction [32]. In addition, there was no change observed in the absorption spectra of He (Fe³⁺ deficient) reacting with H₂O₂ + BOH in Figures 3(c). It indicated that Fe²⁺, Fe³⁺ or He (Fe³⁺ deficient) with only porphyrin rings were unable to catalyze the oxidation of BOH by H₂O₂. It could be seen from Figures 3(d-f), the characteristic absorption peaks of BOH at 568 nm gradually decreased, and new absorption peaks at 505 nm gradually increased in the reactions of Hc, Hh or It with Fe−N coordination structures with H₂O₂ + BOH, respectively. These findings indicated that Hc, Hh or It with Fe−N coordination structures were capable of catalyzing the oxidation of BOH by H₂O₂, which were attributed to the coordination structures between Fe and N in Hc, Hh or It. Furthermore, the results suggested that the oxidation sites were located at the vinyl group (C=C) between the p-hydroxyphenyl and BODIPY parent in BOH.

The UV-Vis absorption spectra of (a) BOH + H2O2 + Fe2+, (b) BOH + H2O2 + Fe3+, (c) BOH + H2O2 + Hematoporphyrin (He), (d) BOH + H2O2 + Hemin (Hc), (e) BOH + H2O2 + Hematin porcine (Hh), (f) BOH + H2O2 + Iron(IIII) Meso-Tetraphenylporphine Chloride (It) with 18 cycles in a span of 204 s.

In addition to the catalytic effect of Fe coordinated with N in the iron porphyrin on BOH + H₂O₂, the catalytic effect of the synthesized Fe and N complexes on BOH + H₂O₂ was further investigated. Recently, the bidentate N−donor ligands of 1,10-phenanthroline (o-phen) and 2,2’-Bipyridine have been extensively studied for their coordination ability with iron in various fields such as catalysis, molecular biology, organometallic, and supramolecular chemistry [27,28,33]. Therefore, two N-containing ligands, 1,10-phenanthroline (o-phen) and 2,2’-Bipyridine, were selected as coordination ligands dissolved in anhydrous ethanol to prepare iron complexes. These complexes, Fe³⁺ with 1,10-phenanthroline (o-phen) and Fe³⁺ with 2,2’-Bipyridine, were then utilized as peroxidase-like catalysts with H₂O₂ to catalyze the oxidation of BOH + H₂O₂. The absorption spectra of BOH + H₂O₂ + Fe³⁺ + o-phen and BOH + H₂O₂ + Fe³⁺ + 2,2’-Bipyridine revealed a decrease in the characteristic absorption peak of BOH at 568 nm and a rapid increase in the absorption peak of new products at 505 nm in Figures 4(a and b). It indicated that the synthetic complexes of Fe³⁺ with 1,10-phenanthroline (o-phen) or 2,2’-Bipyridine also exhibited catalytic activity towards the reaction of BOH + H₂O₂. Consequently, the coordination between Fe and N, acting as a peroxidase-like catalyst with H₂O₂ as the oxidant, played a crucial role in catalyzing the oxidation of BOH by H₂O₂.

(a) The absorption spectra of BOH + H2O2 + Fe3+ + 1,10-phenanthroline (o-phen) with 18 cycles in a span of 204 s. (b) The absorption spectra of BOH + H2O2+ Fe3+ + 2,2’-Bipyridine with 18 cycles in a span of 204 s.

3.4. The catalysis of hemoproteins in the oxidation of BOH by H₂O₂

Due to Cytochrome c (Cyt-c) as a kind of hemoproteins with iron porphyrin, the effects of other hemoproteins with iron porphyrin structure, myoglobin (Mb), hemoglobin (Hb), on the reaction of BOH + H₂O₂ were further investigated. The absorption spectra of BOH + H₂O₂ + Cyt-c, BOH + H₂O₂ + Mb, BOH + H₂O₂ + Hb were measured with 10 cycles in a time frame of 108 s. the characteristic absorption peak of BOH at 568 nm decreased rapidly, while the new absorption peaks at 505 nm emerged in Figures 5(a-c). It indicated that the other hemoproteins, myoglobin (Mb) and hemoglobin (Hb), similar to Cyt-c, also possessed the ability to catalyze the oxidation of BOH with H₂O₂. However, despite all three hemoproteins containing the iron porphyrin structure, there were noticeable differences in the reaction rates of the hemoproteins + H₂O₂ + BOH systems under identical conditions. As shown in Figure 5(d) and Table 1, the chemical reaction rate constants of BOH + H₂O₂ + Cyt-c, BOH + H₂O₂ + Mb and BOH + H₂O₂ + Hb were measured at 568 nm. The chemical reaction rate constants followed the order of Cyt-c > Mb > Hb. Cyt-c and BOH + H₂O₂ exhibited a rapid reaction, whereas the reaction of the other two proteins, Mb or Hb, with BOH + H₂O₂ was relatively slow. This indicated that the reaction of BOH + H₂O₂ demonstrated a certain selectivity towards Cyt-c with peroxidase activity.

(a) The absorption spectra of BOH + H2O2 + Cyt-c with 10 cycles in a time frame of 108 s. (b) The absorption spectra of BOH + H2O2 + Mb with 10 cycles in a time frame of 108 s. (c) The absorption spectra of BOH + H2O2 + Hb with 10 cycles in a time frame of 108 s. (d) The chemical kinetics of BOH + H2O2 + Cyt-c, BOH + H2O2 + Mb and BOH + H2O2 + Hb measured at 568 nm.

Table 1. The chemical reaction rate constants (k) of BOH + H₂O₂ + Cyt-c, BOH + H₂O₂ + Mb and BOH + H₂O₂ + Hb measured at 568 nm.

Rate constant	BOH + H₂O₂ + Cyt-c	BOH + H₂O₂ + Mb	BOH + H₂O₂ + Hb
k (s^-1)	0.0240	0.0053	0.0050

The spatial structures of heme binding sites in three hemoproteins (Cyt-c, Mb and Hb) were analyzed to investigate the reasons for the different reaction rates of H₂O₂ oxidation of BOH catalyzed by these proteins. On the one hand, the Cyt-c from horse heart, which was mainly in the reduced form with the active peroxidase being the five-coordinate form, facilitated the rapid catalysis of substrate oxidation by hydrogen peroxide [21]. Additionally, there were differences in the distribution positions of −CH₂−CH₂−COOH groups around the iron porphyrin ring among the three hemoproteins shown in the surface structures of three hemoproteins in Figures 6(a-c). In Cyt-c, the −CH₂−CH₂−COOH group was distributed parallel to the plane of the iron porphyrin ring, while in Mb and Hb, the −CH₂−CH₂−COOH groups were distributed vertically above and below the plane of the iron porphyrin ring. Therefore, due to the spatial orientation of the catalytic sites, there might be the significant steric hindrance effect in the binding of Mb or Hb to the substrate BOH compared to Cyt-c, resulting in a significant decrease in the catalytic efficiency of Mb or Hb for the oxidation of BOH by H₂O₂. The reaction rate of Cyt-c catalyzed H₂O₂ oxidation of BOH was faster than that of Mb and Hb, indicating that Cyt-c, as a peroxidase, was more suitable for catalyzing H₂O₂ oxidation of BOH.

(a) The surface structure of cytochrome c (Protein Data Bankentry 1HRC). (b) The surface structure of āmyoglobin surface (Protein Data Bank entry 1WLA). (c) The surface structure of hemoglobin surface (Protein Data Bank entry 2QSS).

4. Conclusions

In this work, Cyt-c as a peroxidase could catalyze the oxidation of a p-hydroxystyryl-substituted BODIPY derivative (BOH) by H₂O₂ based on the spectral changes of BOH with the oxidation site being the vinyl group (C=C) between the hydroxyphenyl group and the dipyrrole in BOH. The stable structure of BOH was calculated that the BODIPY basic structure with a p-hydroxystyryl group was perpendicular to the benzene ring containing a carboxyl group. The BODIPY basic structure with a p-hydroxystyryl group in BOH was also dedicated to the fluorescence emission of BOH. By comparing the catalytic effects of Fe²⁺, Fe³⁺, hematoporphyrin (He, Fe³⁺ deficient), hemin (Hc), hematin porcine (Hh), Iron(IIII) Meso-Tetraphenylporphine chloride (It)) and two synthetic complexes of Fe³⁺ with 1,10-phenanthroline (o-phen) and Fe³⁺ with 2,2’-Bipyridine on the oxidation of BOH by H₂O₂, it indicated that Fe with Fe−N coordination state as peroxidase-like catalyst could catalyze the oxidation of BOH by H₂O₂. Additionally, myoglobin (Mb) and hemoglobin (Hb), two hemoproteins, also exhibited catalytic activity in the oxidation of BOH by H₂O₂, although at a slower rate compared to Cyt-c. This difference in reaction rates might be due to the composition of Cyt-c from horse heart, which mainly consisted of the reduced form with the five-coordinate form acting as an active peroxidase. Furthermore, there was the significant steric hindrance effect in the binding of Mb or Hb to the substrate BOH in comparison with Cyt-c, which was attributed to differences in the distribution positions of −CH₂−CH₂−COOH groups and the iron porphyrin rings, as determined by crystal structure analysis. It is expected to broaden the scope of the p-hydroxystyryl-substituted BODIPY derivatives application in H₂O₂ catalytic oxidation and fluorescence sensing.

Acknowledgment

This work was supported by the New Faculty Start-Up Fund of Zaozhuang University (1020752), the National Natural Science Foundation of China (21673289, 21273282).

CRediT authorship contribution statement

Qinhai Xu (Corresponding author): Experimental studies, Data acquisition, Data analysis, Manuscript preparation, Literature search, Manuscript editing and review. Kang Li: Data analysis. Yang Liu: Data acquisition, Data analysis. Delong Kong: Data analysis. Peng Wang: Manuscript editing and review, Manuscript editing and review.

Declaration of competing interest

There are no conflicts of interest.

Data availability

Data will be made available on request.

Declaration of generative AI and AI-assisted technologies in the writing process

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Supplementary data

Supplementary material to this article can be found online at https://dx.doi.org/10.25259/AJC_938_2025.

References

Kowada T., Maeda H., Kikuchi K.. BODIPY-based probes for the fluorescence imaging of biomolecules in living cells. Chemical Society Reviews. 2015;44:4953-4972. https://doi.org/10.1039/c5cs00030k
[Google Scholar]
Gao H., Gao Y., Wang C., Hu D., Xie Z., Liu L., Yang B., Ma Y.. Anomalous effect of intramolecular charge transfer on the light emitting properties of BODIPY. ACS Applied Materials & Interfaces. 2018;10:14956-14965. https://doi.org/10.1021/acsami.7b13444
[Google Scholar]
Loudet A., Burgess K.. BODIPY dyes and their derivatives: Syntheses and spectroscopic properties. Chemical Reviews. 2007;107:4891-4932. https://doi.org/10.1021/cr078381n
[Google Scholar]
Jantra S., Butta P., Jithavech P., Rojsitthisak P., Palaga T., Rashatasakhon P., Sukwattanasinitt M., Wacharasindhu S.. “Turn on” orange fluorescent probe based on styryl-BODIPY for detection of hypochlorite and its application in live cell imaging. Dyes and Pigments. 2019;162:189-195. https://doi.org/10.1016/j.dyepig.2018.10.007
[Google Scholar]
Qu X., Bian Y., Yang B., Zhen S.. A visible BODIPY probe for ‘Naked-Eye’ Detection of pH value and intracellular Fe³⁺. Chinese Journal of Inorganic Chemistry. 2019;35:649-657. http://doi.org/10.11862/CJIC.2019.089
[Google Scholar]
Xu Y., Lin S., He R., Zhang Y., Gao Q., Ng D.K.P., Geng J.. C=C Bond oxidative cleavage of BODIPY photocages by visible light. Chemistry (Weinheim an der Bergstrasse, Germany). 2021;27:11268-11272. https://doi.org/10.1002/chem.202101833
[Google Scholar]
Wang L., Fang G., Cao D.. A novel phenol-based BODIPY chemosensor for selective detection Fe³⁺ with colorimetric and fluorometric dual-mode. Sensors and Actuators B: Chemical. 2015;207:849-857. https://doi.org/10.1016/j.snb.2014.10.110
[Google Scholar]
Shao J., Guo H., Ji S., Zhao J.. Styryl-BODIPY based red-emitting fluorescent OFF–ON molecular probe for specific detection of cysteine. Biosensors and Bioelectronics. 2011;26:3012-3017. https://doi.org/10.1016/j.bios.2010.12.004
[Google Scholar]
Darendelioglu E.. Caffeic acid suppresses HT-29 cell death induced by H₂O₂ via oxidative stress and apoptosis. Bratislava Medical Journal. 2020;121:805-811. https://doi.org/10.4149/BLL_2020_132
[Google Scholar]
Deng Z., Gong Y., Luo Y., Tian Y.. WO₃ nanostructures facilitate electron transfer of enzyme: Application to detection of H₂O₂ with high selectivity. Biosensors & Bioelectronics. 2009;24:2465-2469. https://doi.org/10.1016/j.bios.2008.12.037
[Google Scholar]
Wang X., Zhou L., Qiang F., Wang F., Wang R., Zhao C.. Development of a BODIPY-based ratiometric fluorescent probe for hypochlorous acid and its application in living cells. Analytica Chimica Acta. 2016;911:114-120. https://doi.org/10.1016/j.aca.2016.01.022
[Google Scholar]
Zhang C., Liu X., Xu Z., Liu D.. Multichannel stimulus-responsive nanoprobes for H₂O₂ sensing in diverse biological milieus. Analytical Chemistry. 2020;92:12639-12646. https://doi.org/10.1021/acs.analchem.0c02769
[Google Scholar]
Lee S.H., Kim K.H., Seo S.E., Kim M., il, Park S.J., Kwon O.S.. Cytochrome C-decorated graphene field-effect transistor for highly sensitive hydrogen peroxide detection. Journal of Industrial and Engineering Chemistry. 2020;83:29-34. https://doi.org/10.1016/j.jiec.2019.11.009
[Google Scholar]
Fatima B., Hussain D., Bashir S., Hussain H.T., Aslam R., Nawaz R., Rashid H.N., Bashir N., Majeed S., Ashiq M.N., Najam-Ul-Haq M.. Catalase immobilized antimonene quantum dots used as an electrochemical biosensor for quantitative determination of H₂O₂ from CA-125 diagnosed ovarian cancer samples. Materials Science & Engineering. C, Materials for Biological Applications. 2020;117:111296. https://doi.org/10.1016/j.msec.2020.111296
[Google Scholar]
Xu Q., Li K., Cui H., Peng J., Ji W., Zhang W.. Synthesis of o-phenylenediamine-based Zn-doped carbon dots with excitationindependent emission for the qualitative detection of ClO−. Arabian Journal of Chemistry. 2025;18:2792025. https://doi.org/10.25259/AJC_279_2025
[Google Scholar]
Mano C.M., Barros M.P., Faria P.A., Prieto T., Dyszy F.H., Nascimento O.R., Nantes I.L., Bechara E.J.. Superoxide radical protects liposome-contained cytochrome c against oxidative damage promoted by peroxynitrite and free radicals. Free Radical Biology & Medicine. 2009;47:841-849. https://doi.org/10.1016/j.freeradbiomed.2009.06.028
[Google Scholar]
Zhao H.Z., Du Q., Li Z.S., Yang Q.Z.. Mechanisms for the direct electron transfer of cytochrome c induced by multi-walled carbon nanotubes. Sensors (Basel, Switzerland). 2012;12:10450-10462. https://doi.org/10.3390/s120810450
[Google Scholar]
Patriarca A., Polticelli F., Piro M.C., Sinibaldi F., Mei G., Bari M., Santucci R., Fiorucci L.. Conversion of cytochrome c into a peroxidase: Inhibitory mechanisms and implication for neurodegenerative diseases. Archives of Biochemistry and Biophysics. 2012;522:62-69. https://doi.org/10.1016/j.abb.2012.03.028
[Google Scholar]
Godoy L.C., Muñoz-Pinedo C., Castro L., Cardaci S., Schonhoff C.M., King M., Tórtora V., Marín M., Miao Q., Jiang J.F., Kapralov A., Jemmerson R., Silkstone G.G., Patel J.N., Evans J.E., Wilson M.T., Green D.R., Kagan V.E., Radi R., Mannick J.B.. Disruption of the M80-Fe ligation stimulates the translocation of cytochrome c to the cytoplasm and nucleus in nonapoptotic cells. Proceedings of the National Academy of Sciences of the United States of America. 2009;106:2653-2658. https://doi.org/10.1073/pnas.0809279106
[Google Scholar]
Vladimirov Y.A., Proskurnina E.V., Izmailov D.Y., Novikov A.A., Brusnichkin A.V., Osipov A.N., Kagan V.E.. Mechanism of activation of cytochrome C peroxidase activity by cardiolipin. Biochemistry. Biokhimiia. 2006;71:989-997. https://doi.org/10.1134/s0006297906090070
[Google Scholar]
Yin V., Shaw G.S., Konermann L.. Cytochrome c as a peroxidase: Activation of the precatalytic native state by H₂O₂-induced covalent modifications. Journal of the American Chemical Society. 2017;139:15701-15709. https://doi.org/10.1021/jacs.7b07106
[Google Scholar]
Yin V., Holzscherer D., Konermann L.. Delineating heme-mediated versus Direct protein oxidation in peroxidase-activated cytochrome c by top-down mass spectrometry. Biochemistry. 2020;59:4108-4117. https://doi.org/10.1021/acs.biochem.0c00609
[Google Scholar]
Lu Y., Ke H., Wang Y., Zhang Y., Li H., Huang C., Jia N.. A ratiometric electrochemiluminescence resonance energy transfer platform based on novel dye BODIPY derivatives for sensitive detection of lactoferrin. Biosensors & Bioelectronics. 2020;170:112664. https://doi.org/10.1016/j.bios.2020.112664
[Google Scholar]
Kolemen S., Bozdemir O.A., Cakmak Y., Barin G., Erten-Ela S., Marszalek M., Yum J.H., Zakeeruddin S.M., Nazeeruddin M.K., Grätzel M., Akkaya E.U.. Optimization of distyryl-Bodipy chromophores for efficient panchromatic sensitization in dye sensitized solar cells. Chemical Science. 2011;2:949. https://doi.org/10.1039/c0sc00649a
[Google Scholar]
Xu Q., Li K., Wang P.. The reaction mechanism of p-hydroxystyryl-substituted BODIPY with ABTS^•+ and Fe³⁺ in solutions and in liposomes. Arabian Journal of Chemistry. 2025;18:106041. https://doi.org/10.1016/j.arabjc.2024.106041
[Google Scholar]
Avdeeva V., Vologzhanina A., Goeva L., Malinina E., Kuznetsov N.. Boron cluster anions [BnHn]2- (n = 10, 12) in reactions of iron(II) and iron(III) complexation with 2,2′-bipyridyl and 1,10-phenanthroline. Zeitschrift Fur Anorganische Und Allgemeine Chemie. 2015;640:2149-2160. https://doi.org/10.1002/zaac.201400137
[Google Scholar]
Zhang L., Hou Y., Guo X., Liu W., Lv C., Zhang C., Jin Y., Li B.. Fe(III) bipyridyl or phenanthroline complexes with oxidase‐like activity for sensitive colorimetric detection of glutathione. Luminescence. 2020;35:1350-1359. https://doi.org/10.1002/bio.3897
[Google Scholar]
Ren R., Cai G., Yu Z., Tang D.. Glucose-loaded liposomes for amplified colorimetric immunoassay of streptomycin based on enzyme-induced iron(II) chelation reaction with phenanthroline. Sensors and Actuators B: Chemical. 2018;265:174-181. https://doi.org/10.1016/j.snb.2018.03.049
[Google Scholar]
Etienne T., Gattuso H., Monari A., Assfeld X.. QM/MM modeling of Harmane cation fluorescence spectrum in water solution and interacting with DNA. Computational and Theoretical Chemistry. 2014;1040-1041:367-372. https://doi.org/10.1016/j.comptc.2014.03.026
[Google Scholar]
Mahaan R., Narendran M.G., John Alphin J., John Bosco A.. Combined DFT and QM/MM modeling on multifunctional TADF sensitizers and hot-exciton emitters via carborane triads for blue hyperfluorescent OLEDs. Journal of Physical Chemistry A. A. 2024;128:2611-2628. https://doi.org/10.1021/acs.jpca.4c00085
[Google Scholar]
Jantra S., Palaga T., Rashatasakhon P., Sukwattanasinitt M., Wacharasindhu S.. A “turn on” fluorometric and colorimetric probe based on vinylphenol-BODIPY for selective detection of Au(III) ion in solution and in living cells. Dyes and Pigments. 2021;191:109341. https://doi.org/10.1016/j.dyepig.2021.109341
[Google Scholar]
Tian X., Schaich K.. Effects of molecular structure on kinetics and dynamics of the trolox equivalent antioxidant capacity assay with ABTS^•+. Journal Of Agricultural And Food Chemistry. 2013;61:5511-5519. https://doi.org/10.1021/jf4010725
[Google Scholar]
Schöne S., Radoske T., März J., Stumpf T., Ikeda-Ohno A.. Synthesis and characterization of heterometallic iron–Uranium complexes with a bidentate N-donor ligand (2,2′-Bipyridine or 1,10-Phenanthroline) Inorganic Chemistry. 2018;57:13318-13329. https://doi.org/10.1021/acs.inorgchem.8b01868
[Google Scholar]

1. Introduction

2. Materials and Methods

2.1. Reagents and apparatus
2.2. Synthesis of BOH
2.3. The effects of the coordination between Fe and N on the oxidation of BOH by H2O2
2.4. The catalysis of hemoproteins on the oxidation of BOH by H2O2

3. Results and Discussion

3.1. The optimized molecular structure of BOH
3.2. The catalysis of Cyt-c in the oxidation of BOH by H2O2
3.3. Effect of the coordination between Fe and N in the reaction of BOH + H2O2
3.4. The catalysis of hemoproteins in the oxidation of BOH by H2O2

4. Conclusions

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[1] Kowada T., Maeda H., Kikuchi K.. BODIPY-based probes for the fluorescence imaging of biomolecules in living cells. Chemical Society Reviews. 2015;44:4953-4972. https://doi.org/10.1039/c5cs00030k
[Google Scholar]

[2] Gao H., Gao Y., Wang C., Hu D., Xie Z., Liu L., Yang B., Ma Y.. Anomalous effect of intramolecular charge transfer on the light emitting properties of BODIPY. ACS Applied Materials & Interfaces. 2018;10:14956-14965. https://doi.org/10.1021/acsami.7b13444
[Google Scholar]

[3] Loudet A., Burgess K.. BODIPY dyes and their derivatives: Syntheses and spectroscopic properties. Chemical Reviews. 2007;107:4891-4932. https://doi.org/10.1021/cr078381n
[Google Scholar]

[4] Jantra S., Butta P., Jithavech P., Rojsitthisak P., Palaga T., Rashatasakhon P., Sukwattanasinitt M., Wacharasindhu S.. “Turn on” orange fluorescent probe based on styryl-BODIPY for detection of hypochlorite and its application in live cell imaging. Dyes and Pigments. 2019;162:189-195. https://doi.org/10.1016/j.dyepig.2018.10.007
[Google Scholar]

[5] Qu X., Bian Y., Yang B., Zhen S.. A visible BODIPY probe for ‘Naked-Eye’ Detection of pH value and intracellular Fe³⁺. Chinese Journal of Inorganic Chemistry. 2019;35:649-657. http://doi.org/10.11862/CJIC.2019.089
[Google Scholar]

[6] Xu Y., Lin S., He R., Zhang Y., Gao Q., Ng D.K.P., Geng J.. C=C Bond oxidative cleavage of BODIPY photocages by visible light. Chemistry (Weinheim an der Bergstrasse, Germany). 2021;27:11268-11272. https://doi.org/10.1002/chem.202101833
[Google Scholar]

[7] Wang L., Fang G., Cao D.. A novel phenol-based BODIPY chemosensor for selective detection Fe³⁺ with colorimetric and fluorometric dual-mode. Sensors and Actuators B: Chemical. 2015;207:849-857. https://doi.org/10.1016/j.snb.2014.10.110
[Google Scholar]

[8] Shao J., Guo H., Ji S., Zhao J.. Styryl-BODIPY based red-emitting fluorescent OFF–ON molecular probe for specific detection of cysteine. Biosensors and Bioelectronics. 2011;26:3012-3017. https://doi.org/10.1016/j.bios.2010.12.004
[Google Scholar]

[9] Darendelioglu E.. Caffeic acid suppresses HT-29 cell death induced by H₂O₂ via oxidative stress and apoptosis. Bratislava Medical Journal. 2020;121:805-811. https://doi.org/10.4149/BLL_2020_132
[Google Scholar]

[10] Deng Z., Gong Y., Luo Y., Tian Y.. WO₃ nanostructures facilitate electron transfer of enzyme: Application to detection of H₂O₂ with high selectivity. Biosensors & Bioelectronics. 2009;24:2465-2469. https://doi.org/10.1016/j.bios.2008.12.037
[Google Scholar]

[11] Wang X., Zhou L., Qiang F., Wang F., Wang R., Zhao C.. Development of a BODIPY-based ratiometric fluorescent probe for hypochlorous acid and its application in living cells. Analytica Chimica Acta. 2016;911:114-120. https://doi.org/10.1016/j.aca.2016.01.022
[Google Scholar]

[12] Zhang C., Liu X., Xu Z., Liu D.. Multichannel stimulus-responsive nanoprobes for H₂O₂ sensing in diverse biological milieus. Analytical Chemistry. 2020;92:12639-12646. https://doi.org/10.1021/acs.analchem.0c02769
[Google Scholar]

[13] Lee S.H., Kim K.H., Seo S.E., Kim M., il, Park S.J., Kwon O.S.. Cytochrome C-decorated graphene field-effect transistor for highly sensitive hydrogen peroxide detection. Journal of Industrial and Engineering Chemistry. 2020;83:29-34. https://doi.org/10.1016/j.jiec.2019.11.009
[Google Scholar]

[14] Fatima B., Hussain D., Bashir S., Hussain H.T., Aslam R., Nawaz R., Rashid H.N., Bashir N., Majeed S., Ashiq M.N., Najam-Ul-Haq M.. Catalase immobilized antimonene quantum dots used as an electrochemical biosensor for quantitative determination of H₂O₂ from CA-125 diagnosed ovarian cancer samples. Materials Science & Engineering. C, Materials for Biological Applications. 2020;117:111296. https://doi.org/10.1016/j.msec.2020.111296
[Google Scholar]

[15] Xu Q., Li K., Cui H., Peng J., Ji W., Zhang W.. Synthesis of o-phenylenediamine-based Zn-doped carbon dots with excitationindependent emission for the qualitative detection of ClO−. Arabian Journal of Chemistry. 2025;18:2792025. https://doi.org/10.25259/AJC_279_2025
[Google Scholar]

[16] Mano C.M., Barros M.P., Faria P.A., Prieto T., Dyszy F.H., Nascimento O.R., Nantes I.L., Bechara E.J.. Superoxide radical protects liposome-contained cytochrome c against oxidative damage promoted by peroxynitrite and free radicals. Free Radical Biology & Medicine. 2009;47:841-849. https://doi.org/10.1016/j.freeradbiomed.2009.06.028
[Google Scholar]

[17] Zhao H.Z., Du Q., Li Z.S., Yang Q.Z.. Mechanisms for the direct electron transfer of cytochrome c induced by multi-walled carbon nanotubes. Sensors (Basel, Switzerland). 2012;12:10450-10462. https://doi.org/10.3390/s120810450
[Google Scholar]

[18] Patriarca A., Polticelli F., Piro M.C., Sinibaldi F., Mei G., Bari M., Santucci R., Fiorucci L.. Conversion of cytochrome c into a peroxidase: Inhibitory mechanisms and implication for neurodegenerative diseases. Archives of Biochemistry and Biophysics. 2012;522:62-69. https://doi.org/10.1016/j.abb.2012.03.028
[Google Scholar]

[19] Godoy L.C., Muñoz-Pinedo C., Castro L., Cardaci S., Schonhoff C.M., King M., Tórtora V., Marín M., Miao Q., Jiang J.F., Kapralov A., Jemmerson R., Silkstone G.G., Patel J.N., Evans J.E., Wilson M.T., Green D.R., Kagan V.E., Radi R., Mannick J.B.. Disruption of the M80-Fe ligation stimulates the translocation of cytochrome c to the cytoplasm and nucleus in nonapoptotic cells. Proceedings of the National Academy of Sciences of the United States of America. 2009;106:2653-2658. https://doi.org/10.1073/pnas.0809279106
[Google Scholar]

[20] Vladimirov Y.A., Proskurnina E.V., Izmailov D.Y., Novikov A.A., Brusnichkin A.V., Osipov A.N., Kagan V.E.. Mechanism of activation of cytochrome C peroxidase activity by cardiolipin. Biochemistry. Biokhimiia. 2006;71:989-997. https://doi.org/10.1134/s0006297906090070
[Google Scholar]

[21] Yin V., Shaw G.S., Konermann L.. Cytochrome c as a peroxidase: Activation of the precatalytic native state by H₂O₂-induced covalent modifications. Journal of the American Chemical Society. 2017;139:15701-15709. https://doi.org/10.1021/jacs.7b07106
[Google Scholar]

[22] Yin V., Holzscherer D., Konermann L.. Delineating heme-mediated versus Direct protein oxidation in peroxidase-activated cytochrome c by top-down mass spectrometry. Biochemistry. 2020;59:4108-4117. https://doi.org/10.1021/acs.biochem.0c00609
[Google Scholar]

[23] Lu Y., Ke H., Wang Y., Zhang Y., Li H., Huang C., Jia N.. A ratiometric electrochemiluminescence resonance energy transfer platform based on novel dye BODIPY derivatives for sensitive detection of lactoferrin. Biosensors & Bioelectronics. 2020;170:112664. https://doi.org/10.1016/j.bios.2020.112664
[Google Scholar]

[24] Kolemen S., Bozdemir O.A., Cakmak Y., Barin G., Erten-Ela S., Marszalek M., Yum J.H., Zakeeruddin S.M., Nazeeruddin M.K., Grätzel M., Akkaya E.U.. Optimization of distyryl-Bodipy chromophores for efficient panchromatic sensitization in dye sensitized solar cells. Chemical Science. 2011;2:949. https://doi.org/10.1039/c0sc00649a
[Google Scholar]

[25] Xu Q., Li K., Wang P.. The reaction mechanism of p-hydroxystyryl-substituted BODIPY with ABTS^•+ and Fe³⁺ in solutions and in liposomes. Arabian Journal of Chemistry. 2025;18:106041. https://doi.org/10.1016/j.arabjc.2024.106041
[Google Scholar]

[26] Avdeeva V., Vologzhanina A., Goeva L., Malinina E., Kuznetsov N.. Boron cluster anions [BnHn]2- (n = 10, 12) in reactions of iron(II) and iron(III) complexation with 2,2′-bipyridyl and 1,10-phenanthroline. Zeitschrift Fur Anorganische Und Allgemeine Chemie. 2015;640:2149-2160. https://doi.org/10.1002/zaac.201400137
[Google Scholar]

[27] Zhang L., Hou Y., Guo X., Liu W., Lv C., Zhang C., Jin Y., Li B.. Fe(III) bipyridyl or phenanthroline complexes with oxidase‐like activity for sensitive colorimetric detection of glutathione. Luminescence. 2020;35:1350-1359. https://doi.org/10.1002/bio.3897
[Google Scholar]

[28] Ren R., Cai G., Yu Z., Tang D.. Glucose-loaded liposomes for amplified colorimetric immunoassay of streptomycin based on enzyme-induced iron(II) chelation reaction with phenanthroline. Sensors and Actuators B: Chemical. 2018;265:174-181. https://doi.org/10.1016/j.snb.2018.03.049
[Google Scholar]

[29] Etienne T., Gattuso H., Monari A., Assfeld X.. QM/MM modeling of Harmane cation fluorescence spectrum in water solution and interacting with DNA. Computational and Theoretical Chemistry. 2014;1040-1041:367-372. https://doi.org/10.1016/j.comptc.2014.03.026
[Google Scholar]

[30] Mahaan R., Narendran M.G., John Alphin J., John Bosco A.. Combined DFT and QM/MM modeling on multifunctional TADF sensitizers and hot-exciton emitters via carborane triads for blue hyperfluorescent OLEDs. Journal of Physical Chemistry A. A. 2024;128:2611-2628. https://doi.org/10.1021/acs.jpca.4c00085
[Google Scholar]

[31] Jantra S., Palaga T., Rashatasakhon P., Sukwattanasinitt M., Wacharasindhu S.. A “turn on” fluorometric and colorimetric probe based on vinylphenol-BODIPY for selective detection of Au(III) ion in solution and in living cells. Dyes and Pigments. 2021;191:109341. https://doi.org/10.1016/j.dyepig.2021.109341
[Google Scholar]

[32] Tian X., Schaich K.. Effects of molecular structure on kinetics and dynamics of the trolox equivalent antioxidant capacity assay with ABTS^•+. Journal Of Agricultural And Food Chemistry. 2013;61:5511-5519. https://doi.org/10.1021/jf4010725
[Google Scholar]

[33] Schöne S., Radoske T., März J., Stumpf T., Ikeda-Ohno A.. Synthesis and characterization of heterometallic iron–Uranium complexes with a bidentate N-donor ligand (2,2′-Bipyridine or 1,10-Phenanthroline) Inorganic Chemistry. 2018;57:13318-13329. https://doi.org/10.1021/acs.inorgchem.8b01868
[Google Scholar]