Enhancement of single-walled nanotubes luminescence intensity upon dithiothreitol doping

Kurnosov, N. V.; Linnik, A. S.; Leontiev, V. S.; Karachevtsev, V. A.

doi:10.1134/s0030400x14090148

Cited by 4 publications

(9 citation statements)

References 25 publications

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“…Among the selected nanotube species the greatest increase at final concentration is observed for PL bands assigned to (7,5) and (6,5) nanotubes (by 27%), while the emission from (6,4) nanotubes demonstrates a smaller enhancement (∼17%). Note that the similar behaviour of PL from nanotubes with different chiralities was observed upon DTT doping, but the intensity enhancement was greater [11,12]. The strong enhancement can be caused by both greater DTT reducing activity (there are two thiol groups in the DDT structure) and by the difference in the sample preparation (tip sonication was used earlier, which leads to the appearance of more defective nanotubes).…”

Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 53%

“…The efficiency of DNA adsorption depends on the nanotube species and this polymer property was employed for SWNT selection [18]. We observed earlier different PL enhancements for different emission bands upon DTT doping which was explained by the more ordered (or disordered) polymer conformation on the nanotube [11,12]. In that work, the greatest PL enhancement was observed for nanotubes with adsorbed double-stranded DNA, which does not cover the nanotube tightly and is characterized with weaker binding energy with the nanotube surface [19].…”

Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 95%

“…In our case we assume that the defect passivation takes place by the nucleophilic thiol group of the cysteine molecule. This assumption is based on the effective deprotonation of the thiol group and also supported by the fact that such thiol-containing compound as dithiothreitol (DTT) is the strong reducing agent which increases essentially the nanotube PL QY [9,11,12]. PL spectra of SWNT:ssDNA at every cysteine concentration were fitted with a sum of curves described by a function similar to the Voigt function [17].…”

Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 99%

“…Oxygen molecules present in water can form p-defects on the nanotube surface, which serve as effective traps for excitons [8,9]. Passivation of these defects by some organic molecules like dithiothreitol (DDT) or Trolox enhances the QY of the nanotube PL [9][10][11][12]. It was supposed that these reducing agents donate electrons to defective sites on the nanotube surface [9].…”

Section: Introductionmentioning

confidence: 98%

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Influence of cysteine doping on photoluminescence intensity from semiconducting single-walled carbon nanotubes

Kurnosov

Leontiev

Linnik

et al. 2015

Chemical Physics Letters

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Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 53%

Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 95%

Section: Cysteine Influence On Spectral Properties Of Swnts Covered Wmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 98%

See 2 more Smart Citations

Influence of cysteine doping on photoluminescence intensity from semiconducting single-walled carbon nanotubes

Kurnosov

Leontiev

Linnik

et al. 2015

Chemical Physics Letters

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“…The attenuated spectral intensities of the oxidized SWCNTs were restored by the addition of reductants, that is, TCEP‐HCl and DTT (Figure ). DTT as well as other reductants, such as Trolox and β‐mercaptoethanol, have a reducing effect on the SWCNTs dispersed by using deoxyribonucleic acids (DNA) . The reduction, however, was detectable almost exclusively through the restoration of fluorescent intensities but not absorption intensities; that is, insignificant absorbance changes were observed under the conditions .…”

Section: Discussionmentioning

confidence: 99%

Origin of the Surfactant‐Dependent Redox Chemistry of Single‐Wall Carbon Nanotubes

et al. 2016

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The redox chemistry of single-walled carbon nanotubes (SWCNTs) was examined by using optical absorption spectroscopy measurements in the presence of sodiumd odecyl sulfate (SDS) and its analog surfactants, that is, sodium 1-undecanesulfonate (SUS) and sodium dodecylbenzenesulfonate (SDBS). Redox reactions of the SWCNTsw ere observed in the SDS andS US solutions, whereas such reactions were suppressed in the SDBS solution. Molecular dynamics simulations were performed to investigate the assembly of the surfactants arounda nS WCNT.S DS and SUS were shown to primarily form single layers on the SWCNT and certain solvent-exposed areas, whereas SDBS predictably densely coated the SWCNTs. The resultss uggest that the SDBS layer on the SWCNT surfaces preventsc harge-transfer reactions;i n contrast,t he sparse layers of SDS and SUS allow the redox chemistry through the charge-transferr eactions. Interestingly,apositively charged SWCNT as am odel for the oxidized SWCNT showed an increase in the number of surfactant molecules around the SWCNT in the SDS and SUS solutions owing to electrostatic interaction, which is relatedt ot he chirality-dependenceoftheSWCNT colloidalstability.

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Impact of Redox-Active Molecules on the Fluorescence of Polymer-Wrapped Carbon Nanotubes

2016

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The near-infrared (nIR) fluorescence of polymer-wrapped single-walled carbon nanotubes (SWCNTs) is very sensitive to the local chemical environment. It has been shown that certain small reducing molecules can increase the fluorescence of SWCNTs. However, so far the role of the polymer around the SWCNT as well as the mechanism is not understood. Here, we investigated how reducing and oxidizing small molecules affect the nIR fluorescence of polymer-wrapped SWCNTs. Our results show that the polymer plays an essential role. Reducing molecules such as ascorbic acid, epinephrine, and trolox increased the nIR fluorescence up to 250% but only if SWCNTs were suspended in negatively charged polymers such as DNA or poly(acrylic acid) (PAA). In comparison, phospholipid−poly(ethylene glycol) wrapped SWCNTs did not respond at all while positively charged polyallylamine-wrapped SWCNTs were quenched. Oxidized equivalents such as dehydroascorbic acid did not show a clear tendency to quench or increase fluorescence. Only riboflavin with an intermediate oxidation potential and light absorption in the visible range quenched all polymerwrapped SWCNTs. In general, polymer-wrapped SWCNTs that responded to reducing molecules (e.g., +141%, ascorbic acid) also responded to oxidizing molecules (e.g., −81%, riboflavin). Nevertheless, several reducing molecules showed only a small fluorescence increase (NADH, +21%) or even a decrease (glutathione, −14%), which highlights that the redox potential alone cannot explain fluorescence changes. Furthermore, we show that neither changes of absorption cross sections, scavenging of reactive oxygen species (ROS), nor free surface areas on SWCNTs explain the observed patterns. However, results are in agreement either with a redox reaction of the polymer or conformational changes of the polymer that change fluorescence decay routes. In summary, we show that the polymer around SWCNTs governs how redox-active molecules change nIR fluorescence (quantum yield) of SWCNTs. Molecules with a low redox potential (<−0.4 V) are more likely to increase SWCNT fluorescence, but a low redox-potential alone is not sufficient.

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Enhancement of single-walled nanotubes luminescence intensity upon dithiothreitol doping

Cited by 4 publications

References 25 publications

Influence of cysteine doping on photoluminescence intensity from semiconducting single-walled carbon nanotubes

Influence of cysteine doping on photoluminescence intensity from semiconducting single-walled carbon nanotubes

Origin of the Surfactant‐Dependent Redox Chemistry of Single‐Wall Carbon Nanotubes

Impact of Redox-Active Molecules on the Fluorescence of Polymer-Wrapped Carbon Nanotubes

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