Porphyrins in aqueous amphiphilic polymers as peroxidase mimics

Johnstone, R. A. W.; Stocks, Paul A.; Simpson, A. J.

doi:10.1039/a705934e

Cited by 24 publications

(14 citation statements)

References 12 publications

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“…The ESR signal cannot be observed from the reaction between fluorescein and DMPO without visible‐light irradiation (Figure ). Due to concomitant exposure of DMPO and fluorescein to visible light for 5 min, O 2 .− was generated, as verified by a strongly characteristic peak of the typical DMPO–O 2 ⋅− adduct with an intensity ratio of 1:1:1:1(Figure ), demonstrating that fluorescein could catalyze O 2 to generate O 2 .− radicals, similar to the case of oxidase . The intensity of these ESR signals enhanced when visible‐light irradiation time increased to 10 min (Figure ).…”

Section: Resultsmentioning

confidence: 57%

“…Electron spin resonance (ESR) spectroscopy, accepted as a powerful and direct detection method of ROS, was used to further confirm that ROS was involved in the oxidation, unequivocally with DMPO as spin traps for O 2 .− . The ESR signal cannot be observed from the reaction between fluorescein and DMPO without visible‐light irradiation (Figure ).…”

Section: Resultsmentioning

confidence: 99%

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Fluorescein as a Visible‐Light‐Induced Oxidase Mimic for Signal‐Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction

Liu

Sun

Yang

et al. 2018

Chemistry A European J

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We have found that fluorescein possesses high visible-light-induced oxidase mimetic activity and could transform colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (oxTMB) without unstable and destructive H O under visible-light illumination. Instead, fluorescein uses oxygen as a mild and green electron acceptor, and its activity can be easily controlled by the switching "on/off" of visible light. In addition, the visible-light-induced catalytic mechanism was elucidated in detail and, as the main reactive species h and O accounted for TMB oxidation. Based on the fact that fluorescein diacetate (FDA) possessed no activity and generated active fluorescein in situ in the presence of carboxylesterase (CaE), a signal-amplified sensing platform through a cascade reaction for CaE detection was constructed. Our proposed sensing system displayed excellent analytical performance for the detection of CaE in a wide linear range from 0.040 to 20 U L with a low detection limit of 0.013 U L . This work not only changes the conventional concept that fluorescein is generally considered to be photocatalytically inert, but also provides a novel sensing strategy by tailoring the enzyme mimetic activity of fluorescein derivatives with analyte.

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Section: Resultsmentioning

confidence: 57%

Section: Resultsmentioning

confidence: 99%

Fluorescein as a Visible‐Light‐Induced Oxidase Mimic for Signal‐Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction

Liu

Sun

Yang

et al. 2018

Chemistry A European J

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“…leading to changes in quantum yields from those found in organic solvents. Various polycyclic aromatic hydrocarbons of importance in environmental studies have been solubilized into water through use of an amphiphilic polymer (16)(17)(18)43). Accordingly, the very water-insoluble but chemically stable hydrophobic porphyrin, 5,10,15,20-retrakisphenylporphyrin or its zinc complex were each dissolved in water containing poly(styrene-4-sodium sulfonate co-2-vinylnaphthalene) (PSSS-VN) and passed through a microporous filter to give clear aqueous solutions.…”

Section: Porphyrins In Aqueous Mediamentioning

confidence: 99%

“…The use of such polymers to carry porphyrin oxidation catalysts as enzyme mimics has been reported ( [16][17][18]. In work to be reported elsewhere, the same solubilizing action has been found to be useful for carrying water-insoluble porphyrin sensitizers for singlet oxygen formation in aqueous suspensions of cancer cells in vitro.…”

Section: Introductionmentioning

confidence: 99%

Determination of Fluorescence Yields, Singlet Lifetimes and Singlet Oxygen Yields of Water-Insoluble Porphyrins and Metalloporphyrins in Organic Solvents and in Aqueous Media

et al. 1999

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Fluorescence quantum yields and singlet lifetimes for a wide range of hydrophilic to hydrophobic porphyrins and metalloporphyrins have been determined in toluene, methanol or acetone. Photosensitized singlet oxygen yields have been determined in the same solvents. For some porphyrins, the same quantities were determined in an aqueous medium, through use of an amphiphilic polymer to solubilize the porphyrin sensitizer and target molecule, 1,3-diphenylisobenzofuran. Because rate constants for the deactivation of singlet oxygen (kd) and for its reaction with a target molecule (k,) are unknown in such aqueous polymer systems, a new method was developed for evaluating yields of singlet oxygen formation that also provides a value for the ratio kdk,. A variation observed in quantum yield of singlet oxygen production for the aqueous polymer system with variation in initial concentration of the target molecule is discussed. 10,15,20-Tetrakisphenylporphvrin la. ,froin benwldehyde mid pyrrole (15.23). Found: C, 85.6; H, 5.0; N, 8.8. Calculated for CaH,oN,: C, 86.0; H, 5.0; N, 9.1%. 5,1O,15,20-Tetrakis(4-methoxyphenyllporp~z~rin Ih, from 4-rnrrhoxybenzaldehyde and pyrrole (23). 5.

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“…Arti®cial peroxidase mimics have been also investigated in recent years, and some of these investigations have involved the design and synthesis of porphyrin derivatives. For example, Takahashi et al (1986) prepared a polyethylene glycol-modi®ed hemin that was soluble and exhibited peroxidase activity in several organic solvents; Johnstone et al (1997) synthesized Mn(III)-tetraphenylporphyrin carried in amphiphilic water-soluble polymers and demonstrated that it had peroxidase activity in an aqueous environment; Kamiya et al (1999) demonstrated that a surfactanthistidine-hemin complex showed peroxidase activity in organic media. On the other hand, the generation of hemin-binding antibody was proposed as another approach to obtain arti®cial peroxidase molecules.…”

Section: Introductionmentioning

confidence: 99%

Peroxidase activity of in vitro‐selected 2′‐amino RNAs

Teramoto

Ichinari

Naoki

et al. 2001

Biotech & Bioengineering

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Peroxidase activities of RNAs containing 2'-amino groups, which were selected as aptamers binding to N-methylmesoporphyrin IX, were investigated. Some clones promoted the oxidation reaction of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) with hydrogen peroxide (H(2)O(2)) in the presence of iron(III)-protoporphyrin (hemin), whereas others did not. Each of them had a different substrate specificity. One of the active clones promoted the oxidation of o-dianisidine and beta-nicotinamide adenine dinucleotide reduced form (NADH) with H(2)O(2) 5 and 15 times faster than hemin only, respectively. On the other hand, one clone that was inactive on oxidation of ABTS exhibited the same level of activity on oxidation of o-dianisidine as that shown by the clone active on ABTS but no activity on NADH. By in vitro selection, we can produce various types of peroxidase-like non-natural RNAs.

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Porphyrins in aqueous amphiphilic polymers as peroxidase mimics

Cited by 24 publications

References 12 publications

Fluorescein as a Visible‐Light‐Induced Oxidase Mimic for Signal‐Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction

Fluorescein as a Visible‐Light‐Induced Oxidase Mimic for Signal‐Amplified Colorimetric Assay of Carboxylesterase by an Enzymatic Cascade Reaction

Determination of Fluorescence Yields, Singlet Lifetimes and Singlet Oxygen Yields of Water-Insoluble Porphyrins and Metalloporphyrins in Organic Solvents and in Aqueous Media

Peroxidase activity of in vitro‐selected 2′‐amino RNAs

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