Tag Archives: gold nanotubes

Gold nanotubes for treating mesothelioma?

An October 26, 2020 news item on Nanowerk describes some new research that may lead the way to treatments for people with asbestos-related cancers (e.g., mesothelioma), Note: A link has been removed,

Gold nanotubes – tiny hollow cylinders one thousandth the width of a human hair – could be used to treat mesothelioma, a type of cancer caused by exposure to asbestos, according to a team of researchers at the Universities of Cambridge and Leeds.

In a study published in journal Small (“Exploring High Aspect Ratio Gold Nanotubes as Cytosolic Agents: Structural Engineering and Uptake into Mesothelioma Cells”), the researchers demonstrate that once inside the cancer cells, the nanotubes absorb light, causing them to heat up, thereby killing the cells.

Here`s an image illustrating the research,

Caption: Confocal fluorescence image of gold nanotures (green) in mesothelioma cells. Credit: Arsalan Azad

An October 27, 2020 University of Cambridge press release (also on EurekAlert but published on Oct. 26, 2020), which originated the news item, describes the context for the research and provides a few more technical details,

More than 2,600 people are diagnosed in the UK each year with mesothelioma, a malignant form of cancer caused by exposure to asbestos. Although the use of asbestos is outlawed in the UK now, the country has the world’s highest levels of mesothelioma because it imported vast amounts of asbestos in the post-war years. The global usage of asbestos remains high, particularly in low- and middle-income countries, which means mesothelioma will become a global problem.

“Mesothelioma is one of the ‘hard-to-treat’ cancers, and the best we can offer people with existing treatments is a few months of extra survival,” said Dr Arsalan Azad from the Cambridge Institute for Medical Research at the University of Cambridge. “There’s an important unmet need for new, effective treatments.”

In 2018, the University of Cambridge was awarded £10million from the Engineering and Physical Sciences Research Council to help develop engineering solutions, including nanotech, to find ways to address hard-to-treat cancers.

In a collaboration between the University of Cambridge and University of Leeds, researchers have developed a form of gold nanotubes whose physical properties are ‘tunable’ – in other words, the team can tailor the wall thickness, microstructure, composition, and ability to absorb particular wavelengths of light.

The researchers added the nanotubes to mesothelioma cells cultured in the lab and found that they were absorbed by the cells, residing close to the nucleus, where the cell’s DNA lies. When the team targeted the cells with a laser, the nanotubes absorbed the light and heated up, killing the mesothelioma cell.

Professor Stefan Marciniak, also from the Cambridge Institute for Medical Research, added: “The mesothelioma cells ‘eat’ the nanotubes, leaving them susceptible when we shine light on them. Laser light is able to penetrate deep into tissue without causing damage to surrounding tissue. It then gets absorbed by the nanotubes, which heat up and, we hope in the future, could be used to cause localised cancer-cell killing.”

The team will be developing the work further to ensure the nanotubes are targeted to cancer cells with less effect on normal tissue.

The nanotubes are made in a two-step process. First, solid silver nanorods are created of the desired diameter. Gold is then deposited from solution onto the surface of the silver. As the gold builds-up at the surface, the silver dissolves from the inside to leave a hollow nanotube.

The approach advanced by the Leeds team allows these nanotubes to be developed at room temperature, which should make their manufacture at scale more feasible.

Professor Stephen Evans from the School of Physics and Astronomy at the University of Leeds said: “Having control over the size and shape of the nanotubes allows us to tune them to absorb light where the tissue is transparent and will allow them to be used for both the imaging and treatment of cancers. The next stage will be to load these nanotubes with medicines for enhanced therapies.”

Here`s a link to and a citation for the paper,

Exploring High Aspect Ratio Gold Nanotubes as Cytosolic Agents: Structural Engineering and Uptake into Mesothelioma Cells by Sunjie Ye, Arsalan A. Azad, Joseph E. Chambers, Alison J. Beckett, Lucien Roach, Samuel C. T. Moorcroft, Zabeada Aslam, Ian A. Prior, Alexander F. Markham, P. Louise Coletta, Stefan J. Marciniak, Stephen D. Evans. Small DOI: https://doi.org/10.1002/smll.202003793 First published: 25 October 2020

This paper is open access.

Gold nanotubes could be used in cancer therapies

Where nanotubes are concerned I don’t often see mention of any type other than ‘carbon’ nanotubes so, this Feb. 12, 2015 nanomedicine news item on ScienceDaily featuring ‘gold’ nanotubes caught my attention,

Scientists have shown that gold nanotubes have many applications in fighting cancer: internal nanoprobes for high-resolution imaging; drug delivery vehicles; and agents for destroying cancer cells.

The study, published today in the journal Advanced Functional Materials, details the first successful demonstration of the biomedical use of gold nanotubes in a mouse model of human cancer.

A Feb. 13, 2015 University of Leeds press release, which originated the news item despite what the publication date suggests, describes the research in more detail (Note: Links have been removed),

Study lead author Dr Sunjie Ye, who is based in both the School of Physics and Astronomy and the Leeds Institute for Biomedical and Clinical Sciences at the University of Leeds, said:  “High recurrence rates of tumours after surgical removal remain a formidable challenge in cancer therapy. Chemo- or radiotherapy is often given following surgery to prevent this, but these treatments cause serious side effects.

Gold nanotubes – that is, gold nanoparticles with tubular structures that resemble tiny drinking straws – have the potential to enhance the efficacy of these conventional treatments by integrating diagnosis and therapy in one single system.”

The researchers say that a new technique to control the length of nanotubes underpins the research. By controlling the length, the researchers were able to produce gold nanotubes with the right dimensions to absorb a type of light called ‘near infrared’.

The study’s corresponding author Professor Steve Evans, from the School of Physics and Astronomy at the University of Leeds, said: “Human tissue is transparent for certain frequencies of light – in the red/infrared region. This is why parts of your hand appear red when a torch is shone through it.

“When the gold nanotubes travel through the body, if light of the right frequency is shone on them they absorb the light. This light energy is converted to heat, rather like the warmth generated by the Sun on skin. Using a pulsed laser beam, we were able to rapidly raise the temperature in the vicinity of the nanotubes so that it was high enough to destroy cancer cells.”

In cell-based studies, by adjusting the brightness of the laser pulse, the researchers say they were able to control whether the gold nanotubes were in cancer-destruction mode, or ready to image tumours.

In order to see the gold nanotubes in the body, the researchers used a new type of  imaging technique called ‘multispectral optoacoustic tomography’ (MSOT) to detect the gold nanotubes in mice, in which gold nanotubes had been injected intravenously. It is the first biomedical application of gold nanotubes within a living organism. It was also shown that gold nanotubes were excreted from the body and therefore are unlikely to cause problems in terms of toxicity, an important consideration when developing nanoparticles for clinical use.

Study co-author Dr James McLaughlan, from the School of Electronic & Electrical Engineering at the University of Leeds, said: “This is the first demonstration of the production, and use for imaging and cancer therapy, of gold nanotubes that strongly absorb light within the ‘optical window’ of biological tissue.

“The nanotubes can be tumour-targeted and have a central ‘hollow’ core that can be loaded with a therapeutic payload. This combination of targeting and localised release of a therapeutic agent could, in this age of personalised medicine, be used to identify and treat cancer with minimal toxicity to patients.”

The use of gold nanotubes in imaging and other biomedical applications is currently progressing through trial stages towards early clinical studies.

Here’s a link to and a citation for the paper,

Engineering Gold Nanotubes with Controlled Length and Near-Infrared Absorption for Theranostic Applications by Sunjie Ye, Gemma Marston, James R. McLaughlan, Daniel O. Sigle, Nicola Ingram, Steven Freear, Jeremy J. Baumberg, Richard J. Bushby, Alexander F. Markham, Kevin Critchley, Patricia Louise Coletta, and Stephen D. Evans. Advanced Functional Materials DOI: 10.1002/adfm.201404358 Article first published online: 12 FEB 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.