Dynamic light scattering from acoustic modes in single-walled carbon nanotubes

Introduction. Single-walled carbon nanotubes (SWCNTs) can affect the human body as a result of their use in packaging materials, growth stimulators of agricultural plants and promising agrochemicals. The aim of the study was to investigate the effect of SWCNT on integral and biochemical indices on the model of oral administration to rats in a subacute experiment with duration of 92 days. Material and methods. SWCNT were dispersed by ultrasound in water with 1% by weight of the non-ionic surfactant Tween 20. According to the data of dynamic light scattering, electron microscopy, and Raman light scattering the sample containing both free and partially aggregated SWCNTs. The experiment was carried out on 5 groups of growing male Wistar rats. The SWCNT dispersion was added to the drinking water at doses (control); of 0.01; 0.1; 1.0 and 10 mg/kg body weight in groups from the 1st to the 5th group. We studied the level of anxiety and cognitive function in the test of the “Conditional Reflex of Passive Avoidance” (CRPA); the mass of internal organs, the permeability of the small intestine wall for ovalbumin macromolecules, the biochemical parameters of blood serum, the activity of glutathione peroxidase, the content of non-protein thiols in the liver, urinary excretion of 8-hydroxy-2’-deoxyguanosine (8-oxo-G) and selenium. Results. As a result of SWCNTs consumption there were found significant changes in the content of total protein, uric acid, triglycerides, cholesterol in the blood serum, the increased activity of aspartate aminotransferase, the relative mass of the liver, and decreased the permeability of the intestinal wall for macromolecules of the protein. There have been shifts in individual antioxidant protection indices, including increased 8-oxo-G excretion, decreased glutathione peroxidase activity, glutathione content in the liver, and selenium availability. Most of the above effects did not show a dose dependence of the nanomaterial and were more pronounced at minimal and medium doses of SWCNTs than at maximum doses. The effect of SWCNTs on the behavioral responses of animals was not revealed. Conclusion. Therefore, SWCNT show signs of toxic effects at a dose of 0.1 mg/kg body weight in a day or less.

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Inelastic light scattering from magnetically aligned single-walled carbon nanotubes and estimate of their two-dimensional Young's modulus

Diamond and Related Materials ◽

10.1016/s0925-9635(02)00227-3 ◽

2003 ◽

Vol 12 (3-7) ◽

pp. 806-810 ◽

Cited By ~ 5

Author(s):

A. Li Bassi ◽

M.G. Beghi ◽

C.S. Casari ◽

C.E. Bottani ◽

A. Podestà ◽

...

Keyword(s):

Carbon Nanotubes ◽

Light Scattering ◽

Young’S Modulus ◽

Young's Modulus ◽

Single Walled Carbon Nanotubes ◽

Two Dimensional ◽

Single Walled Carbon ◽

Inelastic Light Scattering ◽

Walled Carbon Nanotubes ◽

Magnetically Aligned

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Controlled Release of Doxorubicin from the Drug Delivery Formulation Composed of Single-Walled Carbon Nanotubes and Congo Red: A Molecular Dynamics Study and Dynamic Light Scattering Analysis

Pharmaceutics ◽

10.3390/pharmaceutics12070622 ◽

2020 ◽

Vol 12 (7) ◽

pp. 622 ◽

Cited By ~ 1

Author(s):

Anna Jagusiak ◽

Katarzyna Chlopas ◽

Grzegorz Zemanek ◽

Pawel Wolski ◽

Tomasz Panczyk

Keyword(s):

Carbon Nanotubes ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Congo Red ◽

Binding Capacity ◽

Single Walled Carbon Nanotubes ◽

Carrier System ◽

Ph Changes ◽

Ph Dependent ◽

Walled Carbon Nanotubes

The controlled delivery and release of drug molecules at specific targets increases the therapeutic efficacy of treatment. This paper presents a triple complex which is a new potential drug delivery system. Triple complex contains single-walled carbon nanotubes, Congo red, and doxorubicin. Nanotubes are built of a folded graphene layer providing a large surface for binding Congo red via “face-to-face” stacking which markedly increases the binding capacity of the carrier. Congo red is a compound that self-associates to form supramolecular ribbon-like structures, which are able to bind some drugs by intercalation. The nanotube–Congo red complex can bind the model drug doxorubicin. Thus, a new triple carrier system was obtained. The aim of this paper is to present studies on the controlled release of a model anticancer drug from a triple carrier system through pH changes. The specific aim of the study was to model the structure of the obtained experimental systems and to compare the changes in the average energy of interaction between its components induced by pH changes. The studies also aimed to compare the intensity of pH-dependent changes in hydrodynamic diameters of individual components of the triple carrier system. The effect of pH changes on the stability of the analyzed systems was examined using the molecular modeling method and dynamic light scattering. The decrease in pH influenced the structure and stability of the analyzed triple systems and ensured efficient drug release. The changes in hydrodynamic diameters of the obtained fractions were examined with the use of dynamic light scattering and were confirmed by computer simulation methods. The formulation presented in this paper shows potential for a therapeutic application owing to its high drug binding capacity and pH-dependent release. This ensures prolonged local action of the drug. The results reveal that the studied complex fulfills the basic requirements for its potential use as drug carrier, thus reducing side effects and enhancing pharmacological efficacy of drugs.

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