Dual fluorophore–nitroxide probes for analysis of vitamin C in biological liquids

Lozinsky, Evgenia; Martin, Vladimir V.; Berezina, T. A.; Shames, Alexander I.; Weis, Alexander L.; Likhtenshtein, Gertz I.

doi:10.1016/s0165-022x(98)00029-3

Cited by 89 publications

(64 citation statements)

References 18 publications

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“…Several mechanisms have been proposed for quenching by free radicals, for example, exchange induced relaxation processes (intersystem crossing and internal conversion), electron transfer, and energy transfer interactions. 310 The nitroxide-fluorophore systems have been mostly employed to investigate dynamic processes in biochemical systems, 311 to evaluate the reactivity or the concentration of antioxidants in homogeneous or micellar systems (Scheme 5.66), 312,313 for the detection of free radicals, 314 and to study polymer degradation processes due to oxidative damages such as observed in polypropylene for instance. 315 Recently, the development of free radical sensors based on TEMPO functionalized quantum dots has also been reported.…”

Section: Nitroxides As Prefluorescent Probesmentioning

confidence: 99%

Nitroxide Radicals: Properties, Synthesis and Applications

et al. 2010

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Section: Nitroxides As Prefluorescent Probesmentioning

confidence: 99%

Nitroxide Radicals: Properties, Synthesis and Applications

et al. 2010

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“…In this paper, we review the use of three new types of molecular probes: (1) dual fluorophore-nitroxide have been used in the analysis of antioxidants of different reducing capacity. On the basis of the abovementioned unique properties of the dual molecules, a method for the quantitative analysis of vitamin C in biological and chemical liquids has been proposed [16][17][18]. It was shown that, in the presence of ascorbic acid, an increase in the fluorescent intensity and a decay of the EPR signal of the dual probe DT occurred with the same rate constant (Figs.…”

Section: Introductionmentioning

confidence: 99%

“…Thus, in complex systems, it is not the antioxidant concentration but the value of the rate constant of the nitroxide reduction that is the most important quantitative characteristic of the system's antioxidant status. The proposed method was used for the analysis of the antioxidant status of commercial juices and human blood [16,18].…”

Section: Introductionmentioning

confidence: 99%

Novel Fluorescent Methods for Biotechnological and Biomedical Sensoring: Assessing Antioxidants, Reactive Radicals, NO Dynamics, Immunoassay, and Biomembranes Fluidity

Likhtenshtein

2008

Appl Biochem Biotechnol

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We proposed and developed a series of fluorescent methods for analysis and investigation of biological systems with a view of future biotechnological and biomedical applications. The methods we describe have been built upon several photochemical and photophysical phenomena including fluorescent quenching, photochrome photoisomerization, and energy transfer. Three new types of molecular probes have been developed and employed for such studies: (1) dual fluorophore-nitroxide compounds, (2) fluorescence-photochrome molecules, and (3) super molecules containing both fluorescence and fluorescent quenching segments. The fluorescent properties of the new probes were intensively exploited for several practical applications including a real-time analysis of antioxidants, nitric oxide, superoxide, reactive radicals, trinitrotoluene, and metal ions, investigation of molecular dynamics of biomembranes in a wide range characteristic times, detection of protein conformational transition, and characterization of surface system. Owning high sensitivity, simplicity, and availability of fluorescent techniques, these methods can be widely employed and are adaptable to fibrooptic sensoring. A general survey of the physical principles and application of the new fluorescent methods has been provided.

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“…The cleavage of the covalent connection between both moieties would negate the quenching performance. 128 Therefore, the connection of commercially available nitroxides and fluorophores via esterification, 122,123,[129][130][131][132][133][134] amidation, [135][136][137] or sulfonamidation [138][139][140] employed in the early stages of the PFN research are less suitable for efficient PFNs (refer to Scheme 10). The resulting compounds contain long, hydrolysis sensitive linkages.…”

Section: Synthesismentioning

confidence: 99%

“…123 By application of the methodology to several fruit juices, the quenching performance was found to be dependent on the concentration of the ascorbic acid. 149 Furthermore, the presence of…”

Section: Synthesismentioning

confidence: 99%

From UV to NIR light, photo-triggered 1,3 dipolar cycloadditions as a modern ligation method in solution and on surface

Lederhose¹

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angefertigt.Ich erkläre hiermit, dass ich die vorliegende Arbeit im Rahmen der Betreuung durch Prof. tracking. In addition, the trigger wavelength of the pyrene functionalized tetrazole was extended deep into the NIR range via the combination of the NITEC with upconversion nanoparticles (UCNPs). Assisted by the UCNPs, photoinduced ligation of both, small and macromolecules was obtained with irradiation at 974 nm. Full conversion and rapid formation of the desired pyrazoline cycloadducts were observed. In addition, a block copolymer featuring the biological relevant biotin moiety was prepared via NITEC at 974 nm, demonstrating the suitability of the approach for applications in the field of biology. Biotin was found to retain bioactivity after being exposed to the NITEC reaction conditions. The efficient penetration ability of the NIR irradiation applied was verified by 'through tissue' conjugation experiments. After the NITEC reaction was demonstrated to be a powerful ligation tool in solution, the concept was employed for the modification of surfaces in a λ-orthogonal approach. The selective ability of the pyrene tetrazole and an UV-active diaryl tetrazole to undergo independent NITEC reactions at 410 -420 nm, and 320 nm respectively, was demonstrated in solution. Importantly, the UV-active tetrazole remains unreacted if exposed to visible light, even for prolonged irradiation times. Subsequently, a surface grafted with pyrene functional tetrazole and UV-active tetrazole was prepared and utilized for formation of advanced patterned surfaces.

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Dual fluorophore–nitroxide probes for analysis of vitamin C in biological liquids

Cited by 89 publications

References 18 publications

Nitroxide Radicals: Properties, Synthesis and Applications

Nitroxide Radicals: Properties, Synthesis and Applications

Novel Fluorescent Methods for Biotechnological and Biomedical Sensoring: Assessing Antioxidants, Reactive Radicals, NO Dynamics, Immunoassay, and Biomembranes Fluidity

From UV to NIR light, photo-triggered 1,3 dipolar cycloadditions as a modern ligation method in solution and on surface

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