Quenching of fluorene fluorescence by single-walled carbon nanotube dispersions with surfactants: application for fluorene quantification in wastewater

Palencia, Sergio; Vera, S.; Díez‐Pascual, Ana M.; Andrés, María Paz San

doi:10.1007/s00216-015-8669-3

Cited by 13 publications

(13 citation statements)

References 54 publications

(66 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This quenching effect is stronger for the anionic surfactant, likely due to the larger space between the head ionic groups of SDS micelles compared to those of CTAB or DTAB, which makes the penetration of the riboflavin molecule into the micelles easier [ 32 ]. These results significantly differ from those found for the fluorescence of other aromatic molecules like fluorene in the presence of surfactant solutions [ 44 ], where the fluorescence intensity increased in the presence of Brij L23 or CTAB, ascribed to a solubilization effect of fluorene. On the other hand, the comparison of the results obtained for the cationic surfactants CTAB and DTAB, which have identical structure and only differ in the chain length (16 and 12 carbon atoms, respectively) indicates that both have the same effect on the fluorescence of riboflavin.…”

Section: Resultscontrasting

confidence: 98%

Comparison of Anionic, Cationic and Nonionic Surfactants as Dispersing Agents for Graphene Based on the Fluorescence of Riboflavin

et al. 2017

Self Cite

View full text Add to dashboard Cite

Fluorescence quenching is a valuable tool to gain insight about dynamic changes of fluorophores in complex systems. Graphene (G), a single-layered 2D nanomaterial with unique properties, was dispersed in surfactant aqueous solutions of different nature: non-ionic polyoxyethylene-23-lauryl ether (Brij L23), anionic sodium dodecylsulphate (SDS), and cationic hexadecyltrimethylammonium bromide (CTAB) and dodecyltrimethylammonium bromide (DTAB). The influence of the surfactant type, chain length and concentration, G total concentration and G/surfactant weight ratio on the fluorescence intensity of vitamin B2 (riboflavin) was investigated. The quality of the different G dispersions was assessed by scanning and transmission electron microscopies (SEM and TEM). A quenching phenomenon of the fluorescence of riboflavin was found for G dispersions in all the surfactants, which generally becomes stronger with increasing G/surfactant weight ratio. For dispersions in the ionic surfactants, the quenching is more pronounced as the surfactant concentration raises, whilst the non-ionic one remains merely unchanged for the different G/Brij L23 weight ratios. More importantly, results indicate that DTAB solutions are the optimum media for dispersing G sheets, leading to an up to 16-fold drop in the fluorescence intensity. Understanding the mechanism in fluorescence quenching of G dispersions in surfactants could be useful for several optical applications.

show abstract

Section: Resultscontrasting

confidence: 98%

Comparison of Anionic, Cationic and Nonionic Surfactants as Dispersing Agents for Graphene Based on the Fluorescence of Riboflavin

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Experimental results confirm that the magnitude of the quenching effect depends strongly on the nature of the surfactant and only slightly on its chain length, hence on the size of the micelles, and that the cationic surfactants are the most suitable for exfoliating G in aqueous solutions. This is consistent with the results from the previous study [ 24 ], which demonstrated that G dispersions in the cationic surfactants were the most efficient in decreasing the fluorescence intensity of riboflavin. Further, it is also in good agreement with former works [ 25 ] that proved that non-ionic surfactants are less efficient than ionic ones in dispersing G, which suggests that strong G-surfactant interactions are needed to achieve a good G exfoliation, as well as stable and homogenous aqueous dispersions.…”

Section: Resultssupporting

confidence: 93%

“…Unexpectedly, for dispersions in this surfactant, the three G percentages that were studied exerted the same effect on the fluorescence of riboflavin, whereas for dispersions in CTAB, the greater the amount of G, the more pronounced the quenching effect. This unexpected behaviour was explained [ 24 ] when considering that a greater number of DTAB monomers with shorter chain than CTAB can adsorb onto the G flakes. In addition, taking into account that the CMC of DTAB is 15.5 times larger than the CMC of CTAB, the concentration of monomers in the former dispersions is higher, hence resulting in a stronger quenching effect.…”

Section: Resultsmentioning

confidence: 92%

“…A Perkin-Elmer LS-50B spectrophotometer (Perkin-Elmer Instruments, Norwalk, CT, USA) was used to obtain the fluorescence spectra of G dispersions, as reported earlier [ 23 , 24 ]. Tip sonication was performed with a UP400S ultrasonic probe system (Hielscher Ultrasonics GmbH, Teltow, Germany), incorporating a titanium sonotrode of 7 mm diameter and approx 100 mm length.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Graphene Flakes Modified by Dispersion in Surfactant Solutions on the Fluorescence Behaviour of Pyridoxine

et al. 2018

View full text Add to dashboard Cite

The influence of graphene (G) dispersions in different types of surfactants (anionic, non-ionic, and cationic) on the fluorescence of vitamin B6 (pyridoxine) was studied. Scanning electron microscopy (SEM) was used to evaluate the quality of the G dispersions via measuring their flake thickness. The effect of surfactant type and concentration on the fluorescence intensity was analyzed, and fluorescence quenching effects were found for all of the systems. These turn out to be more intense with increasing both surfactant and G concentrations, albeit they do not depend on the G/surfactant weight ratio. For the same G concentration, the magnitude of the quenching follows the order: cationic > non-ionic ≥ anionic. The cationic surfactants, which strongly adsorb onto G via electrostatic attraction, are the most effective dispersing agents and they enable a stronger interaction with the zwitterionic form of the vitamin; the dispersing power improves with increasing the surfactant chain length. The fit of the experimental data to the Stern-Volmer equation suggests either a static or dynamic quenching mechanism for the dispersions in non-ionic surfactants, while those in ionic surfactants show a combined mechanism. The results that were obtained herein have been compared to those that were reported earlier for the quenching of another vitamin, riboflavin, to elucidate how the change in the vitamin structure influences the interactions with G in the surfactant dispersions.

show abstract

“…This assay offers an advantage over other common viability assays because it is readily adapted to evaluate viability of cells grown in three dimensional cultures. Although it is known that CNTs can quench luminesence(Palencia et al, 2015), prior to our studies, it was unknown what impact MWCNTs had on the accuracy of CellTiter-Glo® luminescence measurements. We show that an additional centrifugation step after cell lysis is sufficient to remove MWCNT interference from the assay.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of multiwalled carbon nanotube cytotoxicity in cultures of human brain microvascular endothelial cells grown on plastic or basement membrane

Eldridge

Xing

Fahrenholtz

et al. 2017

Toxicology in Vitro

View full text Add to dashboard Cite

There is a growing interest in the use of multiwalled carbon nanotubes (MWCNTs) to treat diseases of the brain. Little is known about the effects of MWCNTs on human brain microvascular endothelial cells (HBMECs), which make up the blood vessels in the brain. In our studies, we evaluate the cytotoxicity of MWCNTs and acid oxidized MWNCTs, with or without a phospholipid-polyethylene glycol coating. We determined the cytotoxic effects of MWCNTs on both tissue-mimicking cultures of HBMECs grown on basement membrane and on monolayer cultures of HBMECs grown on plastic. We also evaluated the effects of MWCNT exposure on the capacity of HBMECs to form rings after plating on basement membrane, a commonly used assay to evaluate angiogenesis. We show that tissue-mimicking cultures of HBMECs are less sensitive to all types of MWCNTs than monolayer cultures of HBMECs. Furthermore, we found that MWCNTs have little impact on the capacity of HBMECs to form rings. Our results indicate that relative cytotoxicity of MWCNTs is significantly affected by the type of cell culture model used for testing, and supports further research into the use of tissue-mimicking endothelial cell culture models to help bridge the gap between in vitro and in vivo toxicology.

show abstract

Quenching of fluorene fluorescence by single-walled carbon nanotube dispersions with surfactants: application for fluorene quantification in wastewater

Cited by 13 publications

References 54 publications

Comparison of Anionic, Cationic and Nonionic Surfactants as Dispersing Agents for Graphene Based on the Fluorescence of Riboflavin

Comparison of Anionic, Cationic and Nonionic Surfactants as Dispersing Agents for Graphene Based on the Fluorescence of Riboflavin

Effect of Graphene Flakes Modified by Dispersion in Surfactant Solutions on the Fluorescence Behaviour of Pyridoxine

Evaluation of multiwalled carbon nanotube cytotoxicity in cultures of human brain microvascular endothelial cells grown on plastic or basement membrane

Contact Info

Product

Resources

About