Tag Archives: Jeremy Baumberg

Training drugs

This summarizes some of what’s happening in nanomedicine and provides a plug (boost) for the  University of Cambridge’s nanotechnology programmes (from a June 26, 2017 news item on Nanowerk),

Nanotechnology is creating new opportunities for fighting disease – from delivering drugs in smart packaging to nanobots powered by the world’s tiniest engines.

Chemotherapy benefits a great many patients but the side effects can be brutal.
When a patient is injected with an anti-cancer drug, the idea is that the molecules will seek out and destroy rogue tumour cells. However, relatively large amounts need to be administered to reach the target in high enough concentrations to be effective. As a result of this high drug concentration, healthy cells may be killed as well as cancer cells, leaving many patients weak, nauseated and vulnerable to infection.

One way that researchers are attempting to improve the safety and efficacy of drugs is to use a relatively new area of research known as nanothrapeutics to target drug delivery just to the cells that need it.

Professor Sir Mark Welland is Head of the Electrical Engineering Division at Cambridge. In recent years, his research has focused on nanotherapeutics, working in collaboration with clinicians and industry to develop better, safer drugs. He and his colleagues don’t design new drugs; instead, they design and build smart packaging for existing drugs.

The University of Cambridge has produced a video interview (referencing a 1966 movie ‘Fantastic Voyage‘ in its title)  with Sir Mark Welland,

A June 23, 2017 University of Cambridge press release, which originated the news item, delves further into the topic of nanotherapeutics (nanomedicine) and nanomachines,

Nanotherapeutics come in many different configurations, but the easiest way to think about them is as small, benign particles filled with a drug. They can be injected in the same way as a normal drug, and are carried through the bloodstream to the target organ, tissue or cell. At this point, a change in the local environment, such as pH, or the use of light or ultrasound, causes the nanoparticles to release their cargo.

Nano-sized tools are increasingly being looked at for diagnosis, drug delivery and therapy. “There are a huge number of possibilities right now, and probably more to come, which is why there’s been so much interest,” says Welland. Using clever chemistry and engineering at the nanoscale, drugs can be ‘taught’ to behave like a Trojan horse, or to hold their fire until just the right moment, or to recognise the target they’re looking for.

“We always try to use techniques that can be scaled up – we avoid using expensive chemistries or expensive equipment, and we’ve been reasonably successful in that,” he adds. “By keeping costs down and using scalable techniques, we’ve got a far better chance of making a successful treatment for patients.”

In 2014, he and collaborators demonstrated that gold nanoparticles could be used to ‘smuggle’ chemotherapy drugs into cancer cells in glioblastoma multiforme, the most common and aggressive type of brain cancer in adults, which is notoriously difficult to treat. The team engineered nanostructures containing gold and cisplatin, a conventional chemotherapy drug. A coating on the particles made them attracted to tumour cells from glioblastoma patients, so that the nanostructures bound and were absorbed into the cancer cells.

Once inside, these nanostructures were exposed to radiotherapy. This caused the gold to release electrons that damaged the cancer cell’s DNA and its overall structure, enhancing the impact of the chemotherapy drug. The process was so effective that 20 days later, the cell culture showed no evidence of any revival, suggesting that the tumour cells had been destroyed.

While the technique is still several years away from use in humans, tests have begun in mice. Welland’s group is working with MedImmune, the biologics R&D arm of pharmaceutical company AstraZeneca, to study the stability of drugs and to design ways to deliver them more effectively using nanotechnology.

“One of the great advantages of working with MedImmune is they understand precisely what the requirements are for a drug to be approved. We would shut down lines of research where we thought it was never going to get to the point of approval by the regulators,” says Welland. “It’s important to be pragmatic about it so that only the approaches with the best chance of working in patients are taken forward.”

The researchers are also targeting diseases like tuberculosis (TB). With funding from the Rosetrees Trust, Welland and postdoctoral researcher Dr Íris da luz Batalha are working with Professor Andres Floto in the Department of Medicine to improve the efficacy of TB drugs.

Their solution has been to design and develop nontoxic, biodegradable polymers that can be ‘fused’ with TB drug molecules. As polymer molecules have a long, chain-like shape, drugs can be attached along the length of the polymer backbone, meaning that very large amounts of the drug can be loaded onto each polymer molecule. The polymers are stable in the bloodstream and release the drugs they carry when they reach the target cell. Inside the cell, the pH drops, which causes the polymer to release the drug.

In fact, the polymers worked so well for TB drugs that another of Welland’s postdoctoral researchers, Dr Myriam Ouberaï, has formed a start-up company, Spirea, which is raising funding to develop the polymers for use with oncology drugs. Ouberaï is hoping to establish a collaboration with a pharma company in the next two years.

“Designing these particles, loading them with drugs and making them clever so that they release their cargo in a controlled and precise way: it’s quite a technical challenge,” adds Welland. “The main reason I’m interested in the challenge is I want to see something working in the clinic – I want to see something working in patients.”

Could nanotechnology move beyond therapeutics to a time when nanomachines keep us healthy by patrolling, monitoring and repairing the body?

Nanomachines have long been a dream of scientists and public alike. But working out how to make them move has meant they’ve remained in the realm of science fiction.

But last year, Professor Jeremy Baumberg and colleagues in Cambridge and the University of Bath developed the world’s tiniest engine – just a few billionths of a metre [nanometre] in size. It’s biocompatible, cost-effective to manufacture, fast to respond and energy efficient.

The forces exerted by these ‘ANTs’ (for ‘actuating nano-transducers’) are nearly a hundred times larger than those for any known device, motor or muscle. To make them, tiny charged particles of gold, bound together with a temperature-responsive polymer gel, are heated with a laser. As the polymer coatings expel water from the gel and collapse, a large amount of elastic energy is stored in a fraction of a second. On cooling, the particles spring apart and release energy.

The researchers hope to use this ability of ANTs to produce very large forces relative to their weight to develop three-dimensional machines that swim, have pumps that take on fluid to sense the environment and are small enough to move around our bloodstream.

Working with Cambridge Enterprise, the University’s commercialisation arm, the team in Cambridge’s Nanophotonics Centre hopes to commercialise the technology for microfluidics bio-applications. The work is funded by the Engineering and Physical Sciences Research Council and the European Research Council.

“There’s a revolution happening in personalised healthcare, and for that we need sensors not just on the outside but on the inside,” explains Baumberg, who leads an interdisciplinary Strategic Research Network and Doctoral Training Centre focused on nanoscience and nanotechnology.

“Nanoscience is driving this. We are now building technology that allows us to even imagine these futures.”

I have featured Welland and his work here before and noted his penchant for wanting to insert nanodevices into humans as per this excerpt from an April 30, 2010 posting,
Getting back to the Cambridge University video, do go and watch it on the Nanowerk site. It is fun and very informative and approximately 17 mins. I noticed that they reused part of their Nokia morph animation (last mentioned on this blog here) and offered some thoughts from Professor Mark Welland, the team leader on that project. Interestingly, Welland was talking about yet another possibility. (Sometimes I think nano goes too far!) He was suggesting that we could have chips/devices in our brains that would allow us to think about phoning someone and an immediate connection would be made to that person. Bluntly—no. Just think what would happen if the marketers got access and I don’t even want to think what a person who suffers psychotic breaks (i.e., hearing voices) would do with even more input. Welland starts to talk at the 11 minute mark (I think). For an alternative take on the video and more details, visit Dexter Johnson’s blog, Nanoclast, for this posting. Hint, he likes the idea of a phone in the brain much better than I do.

I’m not sure what could have occasioned this latest press release and related video featuring Welland and nanotherapeutics other than guessing that it was a slow news period.

Gold nanoparticles concentrate light so atomic bonds can be viewed

 Artist's impression light waves capable of revealing atomic bonds Credit: NanoPhotonics Cambridge/Bart deNijs

Artist’s impression light waves capable of revealing atomic bonds Credit: NanoPhotonics Cambridge/Bart deNijs

This research upends centuries of scientific thought according to a Nov. 10, 2016 news item on ScienceDaily,

For centuries, scientists believed that light, like all waves, couldn’t be focused down smaller than its wavelength, just under a millionth of a metre. Now, researchers led by the University of Cambridge have created the world’s smallest magnifying glass, which focuses light a billion times more tightly, down to the scale of single atoms.

If they’ve created is a ‘magnifying glass’ as they call it in the news item, then I suppose you could call the ‘pico-cavity’ mentioned in the following press release, a lens.

A Nov. 10, 2016 University of Cambridge press release (also on EurekAlert), which originated the news item, describes the research in more detail,

In collaboration with European colleagues, the team used highly conductive gold nanoparticles to make the world’s tiniest optical cavity, so small that only a single molecule can fit within it. The cavity – called a ‘pico-cavity’ by the researchers – consists of a bump in a gold nanostructure the size of a single atom, and confines light to less than a billionth of a metre. The results, reported in the journal Science, open up new ways to study the interaction of light and matter, including the possibility of making the molecules in the cavity undergo new sorts of chemical reactions, which could enable the development of entirely new types of sensors.

According to the researchers, building nanostructures with single atom control was extremely challenging. “We had to cool our samples to -260°C in order to freeze the scurrying gold atoms,” said Felix Benz, lead author of the study. The researchers shone laser light on the sample to build the pico-cavities, allowing them to watch single atom movement in real time.

“Our models suggested that individual atoms sticking out might act as tiny lightning rods, but focusing light instead of electricity,” said Professor Javier Aizpurua from the Center for Materials Physics in San Sebastian in Spain, who led the theoretical section of this work.

“Even single gold atoms behave just like tiny metallic ball bearings in our experiments, with conducting electrons roaming around, which is very different from their quantum life where electrons are bound to their nucleus,” said Professor Jeremy Baumberg of the NanoPhotonics Centre at Cambridge’s Cavendish Laboratory, who led the research.

The findings have the potential to open a whole new field of light-catalysed chemical reactions, allowing complex molecules to be built from smaller components. Additionally, there is the possibility of new opto-mechanical data storage devices, allowing information to be written and read by light and stored in the form of molecular vibrations.

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

Single-molecule optomechanics in “picocavities” by Felix Benz, Mikolaj K. Schmidt, Alexander Dreismann, Rohit Chikkaraddy, Yao Zhang, Angela Demetriadou, Cloudy Carnegie, Hamid Ohadi, Bart de Nijs, Ruben Esteban, Javier Aizpurua, Jeremy J. Baumberg. Science  11 Nov 2016: Vol. 354, Issue 6313, pp. 726-729 DOI: 10.1126/science.aah5243

This paper is behind a paywall.

Squeezing out ‘polymer opals’ for smart clothing and more

Researchers at the University of Cambridge have developed a technology for producing ‘polymer opals’ on industrial scales according to a June 3, 2016 news item on Nanowerk (Note: A link has been removed),

Using a new method called Bend-Induced-Oscillatory-Shearing (BIOS), the researchers are now able to produce hundreds of metres of these materials, known as ‘polymer opals’, on a roll-to-roll process. The results are reported in the journal Nature Communications (“Large-scale ordering of nanoparticles using viscoelastic shear processing”).

A June 3, 2016 University of Cambridge press release (also on EurekAlert), which originated the news item, provides more detail (Note: Links have been removed),

Researchers have devised a new method for stacking microscopic marbles into regular layers, producing intriguing materials which scatter light into intense colours, and which change colour when twisted or stretched.

Some of the brightest colours in nature can be found in opal gemstones, butterfly wings and beetles. These materials get their colour not from dyes or pigments, but from the systematically-ordered microstructures they contain.

The team behind the current research, based at Cambridge’s Cavendish Laboratory, have been working on methods of artificially recreating this ‘structural colour’ for several years, but to date, it has been difficult to make these materials using techniques that are cheap enough to allow their widespread use.

In order to make the polymer opals, the team starts by growing vats of transparent plastic nano-spheres. Each tiny sphere is solid in the middle but sticky on the outside. The spheres are then dried out into a congealed mass. By bending sheets containing a sandwich of these spheres around successive rollers the balls are magically forced into perfectly arranged stacks, by which stage they have intense colour.

By changing the sizes of the starting nano-spheres, different colours (or wavelengths) of light are reflected. And since the material has a rubber-like consistency, when it is twisted and stretched, the spacing between the spheres changes, causing the material to change colour. When stretched, the material shifts into the blue range of the spectrum, and when compressed, the colour shifts towards red. When released, the material returns to its original colour. Such chameleon materials could find their way into colour-changing wallpapers, or building coatings that reflect away infrared thermal radiation.

I always like it when there are quotes which seem spontaneous (from the press release),

“Finding a way to coax objects a billionth of a metre across into perfect formation over kilometre scales is a miracle [emphasis mine],” said Professor Jeremy Baumberg, the paper’s senior author. “But spheres are only the first step, as it should be applicable to more complex architectures on tiny scales.”

In order to make polymer opals in large quantities, the team first needed to understand their internal structure so that it could be replicated. Using a variety of techniques, including electron microscopy, x-ray scattering, rheology and optical spectroscopy, the researchers were able to see the three-dimensional position of the spheres within the material, measure how the spheres slide past each other, and how the colours change.

“It’s wonderful [emphasis mine] to finally understand the secrets of these attractive films,” said PhD student Qibin Zhao, the paper’s lead author.

There’s also the commercialization aspect to this work (from the press release),

Cambridge Enterprise, the University’s commercialisation arm which is helping to commercialise the material, has been contacted by more than 100 companies interested in using polymer opals, and a new spin-out Phomera Technologies has been founded. Phomera will look at ways of scaling up production of polymer opals, as well as selling the material to potential buyers. Possible applications the company is considering include coatings for buildings to reflect heat, smart clothing and footwear, or for banknote security [emphasis mine] and packaging applications.

There is a Canadian company already selling its anti-counterfeiting (banknote security) bioinspired technology. It’s called Opalux and it’s not the only bioinspired anti-counterfeiting Canadian technology company, there’s also NanoTech Security which takes its inspiration from a butterfly (Blue Morpho) wing.

Getting back to Cambridge, here’s a link to and a citation for the research team’s paper,

Large-scale ordering of nanoparticles using viscoelastic shear processing by Qibin Zhao, Chris E. Finlayson, David R. E. Snoswell, Andrew Haines, Christian Schäfer, Peter Spahn, Goetz P. Hellmann, Andrei V. Petukhov, Lars Herrmann, Pierre Burdet, Paul A. Midgley, Simon Butler, Malcolm Mackley, Qixin Guo, & Jeremy J. Baumberg. Nature Communications 7, Article number: 11661  doi:10.1038/ncomms11661 Published 03 June 2016

This paper is open access.

There is a video demonstrating the stretchability of their ‘polymer opal’ film

It was posted on YouTube three years ago when the researchers were first successful. It’s nice to see they’ve been successful at getting the technology to the commercialization stage.

Cambridge University wants to take its flexible opals to market

Structural colour due to nanoscale structures such as those found on Morpho butterfly wings, jewel beetles, opals, and elsewhere is fascinating to me (Feb. 7, 2013 posting). It would seem many scientists share my fascination  including these groups at the UK’s University of Cambridge and Germany’s Fraunhofer Institute, from the May 30, 2013 University of Cambridge news release (also on EurekAlert),

Instead of through pigments, these ‘polymer opals’ get their colour from their internal structure alone, resulting in pure colour which does not run or fade. The materials could be used to replace the toxic dyes used in the textile industry, or as a security application, making banknotes harder to forge. Additionally, the thin, flexible material changes colour when force is exerted on it, which could have potential use in sensing applications by indicating the amount of strain placed on the material.

The most intense colours in nature – such as those in butterfly wings, peacock feathers and opals – result from structural colour. While most of nature gets its colour through pigments, items displaying structural colour reflect light very strongly at certain wavelengths, resulting in colours which do not fade over time.

In collaboration with the DKI (now Fraunhofer Institute for Structural Durability and System Reliability) in Germany, researchers from the University of Cambridge have developed a synthetic material which has the same intensity of colour as a hard opal, but in a thin, flexible film.

Here’s what the researchers’ synthetic opal looks like,

Polymer Opals Credit: Nick Saffel [downloaded from http://www.cam.ac.uk/research/news/flexible-opals]

Polymer Opals Credit: Nick Saffel [downloaded from http://www.cam.ac.uk/research/news/flexible-opals]

The news release provides a brief description of naturally occurring opals and contrasts them with the researchers’ polymer opals,

Naturally-occurring opals are formed of silica spheres suspended in water. As the water evaporates, the spheres settle into layers, resulting in a hard, shiny stone. The polymer opals are formed using a similar principle, but instead of silica, they are constructed of spherical nanoparticles bonded to a rubber-like outer shell. When the nanoparticles are bent around a curve, they are pushed into the correct position to make structural colour possible. The shell material forms an elastic matrix and the hard spheres become ordered into a durable, impact-resistant photonic crystal.

“Unlike natural opals, which appear multi-coloured as a result of silica spheres not settling in identical layers, the polymer opals consist of one preferred layer structure and so have a uniform colour,” said Professor Jeremy Baumberg of the Nanophotonics Group at the University’s Cavendish Laboratory, who is leading the development of the material.

Like natural opals, the internal structure of polymer opals causes diffraction of light, resulting in strong structural colour. The exact colour of the material is determined by the size of the spheres. And since the material has a rubbery consistency, when it is twisted and stretched, the spacing between spheres changes, changing the colour of the material. When stretched, the material shifts into the blue range of the spectrum, and when compressed, the colour shifts towards red. When released, the material will return to its original colour.

I find the potential for use in the textile industry a little more interesting than the anti-counterfeiting application. (There’s a Canadian company, Nanotech Security Corp., a spinoff from Simon Fraser University, which capitalizes on the Blue Morpho butterfly wing’s nanoscale structures for an anti-counterfeiting application as per my first posting about the company on Jan. 17, 2011.) There has been at least one other attempt to create a textile that exploits structural colour. Unfortunately Teijin Fibres has stopped production of its morphotex, as per my April 12, 2012 posting.

Here’s what the news release has to say about textiles and the potential importance of structural colour,

The technology could also have important uses in the textile industry. “The World Bank estimates that between 17 and 20 per cent of industrial waste water comes from the textile industry, which uses highly toxic chemicals to produce colour,” said Professor Baumberg. “So other avenues to make colour is something worth exploring.” The polymer opals can be bonded to a polyurethane layer and then onto any fabric. The material can be cut, laminated, welded, stitched, etched, embossed and perforated.

The researchers have recently developed a new method of constructing the material, which offers localised control and potentially different colours in the same material by creating the structure only over defined areas. In the new work, electric fields in a print head are used to line the nanoparticles up forming the opal, and are fixed in position with UV light. The researchers have shown that different colours can be printed from a single ink by changing this electric field strength to change the lattice spacing.

As for wanting to take this research to market, from the news release,

Cambridge Enterprise, the University’s commercialisation arm, is currently looking for a manufacturing partner to further develop the technology and take polymer opal films to market.

For more information, please contact sarah.collins@admin.cam.ac.uk.

The reference to opals reminded me of yet another Canadian company exploring the uses of structural colour, Opalux, as per my Jan. 31, 2011 posting.

Mechanics of quantum kissing

“It is as if you can kiss without quite touching lips,” says Professor Jeremy Baumberg from the University of Cambridge Cavendish Laboratory in the University of Cambridge’s Nov. 7, 2012 news release about quantum electron jumps,

Even empty gaps have a colour. Now scientists have shown that quantum jumps of electrons can change the colour of gaps between nano-sized balls of gold. The new results, published today in the journal Nature, set a fundamental quantum limit on how tightly light can be trapped.

The team from the Universities of Cambridge, the Basque Country and Paris have combined tour de force experiments with advanced theories to show how light interacts with matter at nanometre sizes. The work shows how they can literally see quantum mechanics in action in air at room temperature.

As for the kissing, it all starts with metal and jumping electrons,

Because electrons in a metal move easily, shining light onto a tiny crack pushes electric charges onto and off each crack face in turn, at optical frequencies. The oscillating charge across the gap produces a ‘plasmonic’ colour for the ghostly region in-between, but only when the gap is small enough.

Team leader Professor Jeremy Baumberg from the University of Cambridge Cavendish Laboratory suggests we think of this like the tension building between a flirtatious couple staring into each other’s eyes. As their faces get closer the tension mounts, and only a kiss discharges this energy.

H/T to the Nov. 7, 2012 news item on ScienceDaily where I first learned of quantum kissing,

In the new experiments, the gap is shrunk below 1nm (1 billionth of a metre) which strongly reddens the gap colour as the charge builds up. However because electrons can jump across the gap by quantum tunnelling, the charge can drain away when the gap is below 0.35nm, seen as a blue-shifting of the colour. …

Prof Javier Aizpurua, leader of the theoretical team from San Sebastian complains: “Trying to model so many electrons oscillating inside the gold just cannot be done with existing theories.” He has had to fuse classical and quantum views of the world to even predict the colour shifts seen in experiment.

The new insights from this work suggest ways to measure the world down to the scale of single atoms and molecules, and strategies to make useful tiny devices.

Something to think about the next time you kiss.