Potentiometric Study of Carbon Nanotube/Surfactant Interactions by Ion-Selective Electrodes. Driving Forces in the Adsorption and Dispersion Processes

The interaction (adsorption process) of commercial ionic surfactants with non-functionalized and functionalized carbon nanotubes (CNTs) has been studied by potentiometric measurements based on the use of ion-selective electrodes. The goal of this work was to investigate the role of the CNTs’ charge and structure in the CNT/surfactant interactions. Non-functionalized single- (SWCNT) and multi-walled carbon nanotubes (MWCNT), and amine functionalized SWCNT were used. The influence of the surfactant architecture on the CNT/surfactant interactions was also studied. Surfactants with different charge and hydrophobic tail length (sodium dodecyl sulfate (SDS), octyltrimethyl ammonium bromide (OTAB), dodecyltrimethyl ammonium bromide (DoTAB) and hexadecyltrimethyl ammonium bromide (CTAB)) were studied. According to the results, the adsorption process shows a cooperative character, with the hydrophobic interaction contribution playing a key role. This is made evident by the correlation between the free surfactant concentration (at a fixed [CNT]) and the critical micellar concentration, cmc, found for all the CNTs and surfactants investigated. The electrostatic interactions mainly determine the CNT dispersion, although hydrophobic interactions also contribute to this process.

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Spectrophotometric study of interaction and solubilization of procaine hydrochloride in micellar systems

Open Chemistry ◽

10.2478/s11532-008-0078-4 ◽

2009 ◽

Vol 7 (1) ◽

pp. 90-95 ◽

Cited By ~ 2

Author(s):

Reza Hosseinzadeh ◽

Mohammad Gheshlagi ◽

Rahele Tahmasebi ◽

Farnaz Hojjati

Keyword(s):

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Sodium Dodecyl ◽

Spectrophotometric Study ◽

Bulk Water ◽

Procaine Hydrochloride ◽

Ionic Surfactants ◽

Micellar Systems ◽

Aqueous Micellar Solution ◽

Triton X

AbstractThe interaction of Procaine hydrochloride (PC) with cationic, anionic and non-ionic surfactants; cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and triton X-100, were investigated. The effect of ionic and non-ionic micelles on solubilization of Procaine in aqueous micellar solution of SDS, CTAB and triton X-100 were studied at pH 6.8 and 29°C using absorption spectrophotometry. By using pseudo-phase model, the partition coefficient between the bulk water and micelles, Kx, was calculated. The results showed that the micelles of CTAB enhanced the solubility of Procaine higher than SDS micelles (Kx = 96 and 166 for SDS and CTAB micelles, respectively) but triton X-100 did not enhanced the solubility of drug because of weak interaction with Procaine. From the resulting binding constant for Procaine-ionic surfactants interactions (Kb = 175 and 128 for SDS and CTAB surfactants, respectively), it was concluded that both electrostatic and hydrophobic interactions affect the interaction of surfactants with cationic procaine. Electrostatic interactions have a great role in the binding and consequently distribution of Procaine in micelle/water phases. These interactions for anionic surfactant (SDS) are higher than for cationic surfactant (CTAB). Gibbs free energy of binding and distribution of procaine between the bulk water and studied surfactant micelles were calculated.

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Driving Forces and Consequences of the Adsorption of Proteins to Carbon Nanotubes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.441.75 ◽

2010 ◽

Vol 441 ◽

pp. 75-94 ◽

Cited By ~ 2

Author(s):

María F. Mora ◽

Laura E. Valenti ◽

Carlos D. García ◽

Carla E. Giacomelli

Keyword(s):

Carbon Nanotubes ◽

Drug Delivery Systems ◽

Adsorption Process ◽

Driving Forces ◽

Physical Adsorption ◽

Structure And Properties ◽

Covalent Interaction ◽

Chemical Treatments ◽

Pristine Cnts ◽

Recent Developments

Different strategies used to biofunctionalize CNTs with proteins, from direct physical adsorption on pristine CNTs to chemical treatments to achieve covalent interaction, are described. The discussion is focused on the consequences of the adsorption process on the structure and properties of both proteins and CNTs. On this base, recent developments in CNTs-proteins based biosensors (electrochemical and optical) and drug delivery systems are reviewed.

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Dimerization of Recombinant Tobacco Mosaic Virus Movement Protein

Journal of Virology ◽

10.1128/jvi.78.5.3372-3377.2004 ◽

2004 ◽

Vol 78 (7) ◽

pp. 3372-3377 ◽

Cited By ~ 23

Author(s):

Laurence M. Brill ◽

Songpon Dechongkit ◽

Byron DeLaBarre ◽

Jonathon Stroebel ◽

Roger N. Beachy ◽

...

Keyword(s):

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Electrostatic Interactions ◽

Analytical Ultracentrifugation ◽

Movement Protein ◽

Hydrophobic Interactions ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

In Planta ◽

Native Page

ABSTRACT The p30 movement protein (MP) is essential for cell-to-cell spread of tobacco mosaic virus in planta. We used anion-exchange chromatography and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to obtain highly purified 30-kDa MP, which migrated as a single band in native PAGE. Analytical ultracentrifugation suggested that the protein was monodisperse and dimeric in the nonionic detergent n-octyl-β-d-glucopyranoside. Circular dichroism (CD) spectroscopy showed that the detergent-solubilized protein contained significant α-helical secondary structure. Proteolysis of the C-tail generated a trypsin-resistant core that was a mixture of primarily monomers and some dimers. We propose that MP dimers are stabilized by electrostatic interactions in the C terminus as well as hydrophobic interactions between putative transmembrane α-helical coiled coils.

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Adsorption of Phenol from Aqueous Solutions by Carbon Nanomaterials of One and Two Dimensions: Kinetic and Equilibrium Studies

Journal of Nanomaterials ◽

10.1155/2015/405036 ◽

2015 ◽

Vol 2015 ◽

pp. 1-14 ◽

Cited By ~ 18

Author(s):

M. de la Luz-Asunción ◽

V. Sánchez-Mendieta ◽

A. L. Martínez-Hernández ◽

V. M. Castaño ◽

C. Velasco-Santos

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Electrostatic Interactions ◽

Carbon Nanomaterials ◽

Adsorption Process ◽

Chemical Properties ◽

Freundlich Isotherm ◽

Two Dimensions ◽

Multiwalled Carbon ◽

Equilibrium Studies

Carbon nanomaterials have a great potential in environmental studies; they are considered as superior adsorbents of pollutants due to their physical and chemical properties. Functionalization and dimension play an important role in many functions of these nanomaterials including adsorption. In this research, adsorption process was achieved with one-dimension nanomaterials: single walled and multiwalled carbon nanotubes were used as received and after oxidation treatment also two-dimensional nanomaterials were used: graphene oxide and reduced graphene oxide. Carbon nanotubes were modified by hydrogen peroxide under microwave irradiation. The reduction of graphene oxide was achieved by using ascorbic acid.R2values obtained with the pseudo-second-order model are higher than 0.99. The results demonstrate that Freundlich isotherm provides the best fit for the equilibrium data (R2>0.94).RLvalues are between 0 and 1; this represents favorable adsorption between carbon nanomaterials and phenol. The adsorption process occurs byπ-πinteractions and hydrogen bonding and not by electrostatic interactions. The results indicate that the adsorption of phenol on carbon nanomaterials depends on the adsorbents’ surface area, and it is negatively influenced by the presence of oxygenated groups.

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A review on the removal of antibiotics by carbon nanotubes

Water Science & Technology ◽

10.2166/wst.2013.420 ◽

2013 ◽

Vol 68 (8) ◽

pp. 1679-1687 ◽

Cited By ~ 15

Author(s):

Qiao Cong ◽

Xing Yuan ◽

Jiao Qu

Keyword(s):

Carbon Nanotubes ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Organic Chemical ◽

Ecological Health ◽

Research Attention ◽

Freundlich Model ◽

Adsorption Sites ◽

Potential Applications ◽

Potential Risks

Increasing concerns have been raised regarding the potential risks of antibiotics to human and ecological health due to their extensive use. Carbon nanotubes (CNTs) have drawn special research attention because of their unique properties and potential applications as a kind of adsorbents. This review summarizes the currently available research on the adsorption of antibiotics on CNTs, and will provide useful information for CNT application and risk assessment. Four different models, the Freundlich model (FM), Langmuir model (LM), Polanyi–Mane model (PMM), and Dubinin–Ashtakhov model (DAM), are often used to fit the adsorption isotherms. Because different mechanisms may act simultaneously, including electrostatic interactions, hydrophobic interactions, π–π bonds, and hydrogen bonds, the prediction of organic chemical adsorption on CNTs is not straightforward. Properties of CNTs, such as specific surface area, adsorption sites, and oxygen content, may influence the adsorption of antibiotics on CNTs. Adsorption heterogeneity and hysteresis are two features of antibiotic–CNT interactions. In addition, CNTs with adsorbed antibiotics may have potential risks for human health. So, further research examining how to reduce such risks is needed.

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Polycation-Capped CdS Quantum Dots Synthesized in Reverse Microemulsions

Journal of Nanomaterials ◽

10.1155/2012/478153 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Karina Lemke ◽

Joachim Koetz

Keyword(s):

Quantum Dots ◽

Electrostatic Interactions ◽

Sodium Dodecyl ◽

Cds Nanoparticles ◽

Cds Quantum Dots ◽

Fluorescence Measurements ◽

Surfactant Interactions ◽

Reverse Microemulsions ◽

Different Types ◽

Nanoparticle Aggregates

This paper is focused on the formation and recovery of cadmium sulfide (CdS) nanoparticles in two different types of polycation-modified reverse microemulsions using low molecular weight poly(diallyldimethylammonium chloride) (PDADMAC) and poly(ethyleneimine) (PEI). Both polymers were incorporated in a quaternary w/o microemulsion consisting of water, toluene-pentanol (1 : 1), and sodium dodecyl sulfate (SDS), as well as in a ternary w/o microemulsion consisting of water, heptanol, and 3-(N,N-dimethyl-dodecylammonio)-propanesulfonate (SB). UV-vis and fluorescence measurements in the microemulsion illustrate the capping effect of the polycations on the formation of the CdS quantum dots. The nanoparticles are redispersed in water and characterized by using UV-vis and fluorescence spectroscopy, in combination with dynamic light scattering. From the quaternary microemulsion, only nanoparticle aggregates of about 100 nm can be redispersed, but, from the ternary microemulsion, well-stabilized polycation-capped CdS quantum dots can be obtained. The results show that the electrostatic interactions between the polycation and the surfactant are of high relevance especially in the solvent evaporation and redispersion process. That means only that in the case of moderate polycation-surfactant interactions a redispersion of the polymer-capped CdS quantum dots without problems of aggregation is possible.

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Effect of Surfactants on the Dispersion of Multi-Walled Carbon Nanotubes in Epoxy Resin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.221.1 ◽

2011 ◽

Vol 221 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Ying An ◽

Xue Tao He ◽

Wei Min Yang ◽

Yu Mei Ding

Keyword(s):

Carbon Nanotubes ◽

Oleic Acid ◽

Epoxy Resin ◽

Sodium Dodecyl ◽

Ammonium Bromide ◽

Transmission Electron ◽

Balance State ◽

Multi Walled Carbon Nanotubes ◽

Triton X ◽

Walled Carbon Nanotubes

In order to improve the dispersion homogeneity and stabilization of multi-walled carbon nanotubes (MWNT) in epoxy resin, the effect of different surfactants such as hexadecyl trimethyl ammonium bromide (HTAB), sodium dodecyl sulfate (SDS), oleic acid, Triton X-100 and BYK-9077 on the dispersion of MWNT were investigated. Suspensions of MWNTs/epoxy resin with various surfactants were prepared by ultrasonic agitation. Dispersion homogeneity of MWNT in epoxy resin was evaluated by transmission electron microscopy (TEM), and dispersion stabilization was evaluated by stationary observation. The results show that dispersion properties were not improved by HTAB, while they were improved incoordinately by SDS, oleic acid, Triton X-100 and BYK-9077. Suspensions of MWNTs/epoxy resin with HTAB, SDS, oleic acid and Triton X-100 were all delaminated quickly, it means, dispersion stabilization were not improved by these surfactants. BYK-9077 was the only surfactant which enhanced the dispersion homogeneity and stabilization of MWNTs/epoxy resin significantly. Based on this research, various weight ratios of surfactant BYK-9077 to MWNT were studied. The experimental results show that the dispersion system could reach a balance state when the ratio of surfactant BYK-9077 to MWN was 2.

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Protein Corona Composition and Dynamics on Carbon Nanotubes in Blood Plasma and Cerebrospinal Fluid

10.1101/2020.01.13.905356 ◽

2020 ◽

Author(s):

Rebecca L. Pinals ◽

Darwin Yang ◽

Daniel J. Rosenberg ◽

Tanya Chaudhary ◽

Andrew R. Crothers ◽

...

Keyword(s):

Carbon Nanotubes ◽

Cerebrospinal Fluid ◽

Blood Plasma ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Protein Corona ◽

Lipid Binding ◽

Complement C3 ◽

Human Blood Plasma ◽

Corona Formation

AbstractWhen a nanoparticle enters a biological environment, the surface is rapidly coated with proteins to form a “protein corona”. Presence of the protein corona surrounding the nanoparticle has significant implications for applying nanotechnologies within biological systems, affecting outcomes such as biodistribution and toxicity. Herein, we measure protein corona formation on single-stranded DNA wrapped single-walled carbon nanotubes (ssDNA-SWCNTs), a high-aspect ratio nanoparticle ideal for sensing and delivery applications, and polystyrene nanoparticles, a model nanoparticle system. The protein corona of each nanoparticle is studied in human blood plasma and cerebrospinal fluid. We characterize corona composition by proteomic mass spectrometry to determine abundant and differentially enriched vs. depleted corona proteins. High-binding corona proteins on ssDNA-SWCNTs include proteins involved in lipid binding and transport (clusterin and apolipoprotein A-I), complement activation (complement C3), and blood coagulation (fibrinogen). Of note, albumin is the most common blood protein (55% w/v), yet exhibits low-binding affinity towards ssDNA-SWCNTs, displaying 1300-fold lower bound concentration relative to native plasma. We investigate the role of electrostatic and entropic interactions driving selective protein corona formation, and find that hydrophobic interactions drive inner corona formation, while shielding of electrostatic interactions allows for outer corona formation. Lastly, we study real-time binding of proteins on ssDNA-SWCNTs and find relative agreement between proteins that are enriched and bind strongly, such as fibrinogen, and proteins that are depleted and bind marginally, such as albumin. Interestingly, certain proteins express contrary behavior in single-protein experiments than within the whole biofluid, highlighting the importance of cooperative mechanisms driving selective corona adsorption on the SWCNT surface. Knowledge of the protein corona composition, dynamics, and structure informs translation of engineered nanoparticles from in vitro design to effective in vivo application.

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Sorption of Bisphenol A in Aqueous Solutions on Irradiated and as-Grown Multiwalled Carbon Nanotubes

Revista de Chimie ◽

10.37358/rc.18.5.6297 ◽

2018 ◽

Vol 69 (5) ◽

pp. 1233-1239

Author(s):

Raluca Madalina Senin ◽

Ion Ion ◽

Ovidiu Oprea ◽

Rusandica Stoica ◽

Rodica Ganea ◽

...

Keyword(s):

Carbon Nanotubes ◽

Bisphenol A ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Multiwalled Carbon Nanotubes ◽

Adsorption Process ◽

Sorption Process ◽

Multiwalled Carbon ◽

Before And After ◽

Kinetic Sorption

In this study, non-irradiated and weathered multiwalled carbon nanotubes (MWCNTs) obtained through irradiation, were studied as adsorbents for BPA, both nanomaterials being characterized before and after the adsorption process. The objectives of our investigation were to compare the characteristics of non-irradiated and irradiated MWCNTs, to evaluate the adsorption capacity of BPA by pristine and irradiated MWCNTs and to determine the variation of the kinetic, sorption and thermodynamic parameters during sorption process using both sorbents.

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Dispersion of Carbon Nanotubes with “Green” Detergents

Molecules ◽

10.3390/molecules26102908 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2908

Author(s):

Kazuo Umemura ◽

Ryo Hamano ◽

Hiroaki Komatsu ◽

Takashi Ikuno ◽

Eko Siswoyo

Keyword(s):

Carbon Nanotubes ◽

Sodium Dodecyl ◽

Detergent Solution ◽

Absorbance Spectroscopy ◽

Fundamental Research ◽

The Stability ◽

Single Walled Cnts ◽

Better Than ◽

Walled Cnts ◽

Cnt Suspensions

Solubilization of carbon nanotubes (CNTs) is a fundamental technique for the use of CNTs and their conjugates as nanodevices and nanobiodevices. In this work, we demonstrate the preparation of CNT suspensions with “green” detergents made from coconuts and bamboo as fundamental research in CNT nanotechnology. Single-walled CNTs (SWNTs) with a few carboxylic acid groups (3–5%) and pristine multi-walled CNTs (MWNTs) were mixed in each detergent solution and sonicated with a bath-type sonicator. The prepared suspensions were characterized using absorbance spectroscopy, scanning electron microscopy, and Raman spectroscopy. Among the eight combinations of CNTs and detergents (two types of CNTs and four detergents, including sodium dodecyl sulfate (SDS) as the standard), SWNTs/MWNTs were well dispersed in all combinations except the combination of the MWNTs and the bamboo detergent. The stability of the suspensions prepared with coconut detergents was better than that prepared with SDS. Because the efficiency of the bamboo detergents against the MWNTs differed significantly from that against the SWNTs, the natural detergent might be useful for separating CNTs. Our results revealed that the use of the “green” detergents had the advantage of dispersing CNTs as well as SDS.

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