Fluorescent nanoparticles: the super-powered cell mapper
In a surprising scientific crossover, nanoparticles designed for use in solar panels to harness the light of the Sun could be used to shine a light on the human body and map it at a cellular level.
A marvellous scientific universe
It is tempting to think of the various scientific disciplines (physics, chemistry, biology etc.) as being separate from one another — after all, physics is all about calculators and equations, while biology is all about organs and other red sticky bits and bobs. But, like the best individual Marvel movies, there is a surprising amount of crossover.
For example, you might associate a ‘force’ with physics (or, if you are so inclined, with Star Wars, but let’s leave that cinematic universe out of this metaphor) but it is one of these ‘forces’, the strong nuclear force, that makes chemical bonds in molecules possible (chemistry) and it is these molecules that dictate how a biological cell responds (biology). That’s three major scientific universes all linked by just one thing.
Likewise, a discovery that has a certain effect in one thread of the scientific universe can, potentially, be put to a totally different use in another.
Tripping the light (Mr) fantastic
Like the strong nuclear force, another thread that intertwines and connects the scientific universe is the electromagnetic force or, in this case, light energy.
Light is a research tool that crosses all the boundaries of scientific research — after all, it the tool used by humankind’s very first research tool: our eyes; and by one of our first scientific observation inventions: the microscope.
As useful as it is for microscopy, it’s power is doubled in biological research when applied to the field of fluorescence microscopy.
Fluorescence microscopy is rather like taking a highlighter pen to a group of cells being studied in order to pick out the pieces of most interest or to tracking a cell’s moving parts with ease and clarity.
The microscopy component works in the usual way — by carefully manipulating light to magnify small objects and thus make them visible to the human eye. Fluorescence microscopy is an extra, light-fuelled step to enhance the viewing experience — it is microscopy given a superpower.
Scientists add a special dye or coating to a region of interest — this could be a cell, or a particular component inside that cell. This coating will have the quality of fluorescence, meaning if you shine some light on it, it shines it back. It’s like a molecular-level fluorescent jacket… or costume, if you will.
Picking the correct costume
Just as a speedy superhero needs a friction-proof costume, the study of biological material requires that we dress the cells in fluorescent costumes with very particular qualities.
First and foremost, we must avoiding toxic materials that may kill the cell — there’s little point in studying a dead cell. Secondly, we need our costume to be stable and non-reactive so that it doesn’t interfere with the cell’s inner workings.
There is good reason for this — a reactive coating could make a cell behave completely differently to how it does in the body. If we’re trying to understand how our cells function for purposes such as medicine, this could make our results almost meaningless.
The power of nanoparticles!
This is where a fascinating field comes into play: nanoparticles. These are teeny, tiny particles that, thanks to their minute size, have been granted some strange and clever super powers of their own. Thanks to their ridiculously small nature (on the order of one millionth of a millimetre) cells, which are quite small themselves, have no problem taking them on board.
A team at the STFC’s Central Laser Facility (CLF) have been exploring a particular kind of ultra-small nanoparticle that is both non-reactive and fluorescent. It sounds like the perfect material from which to create a cell-tracking fluorescent costume doesn’t it?
Enter the secret identity
Many superheroes have an alter ego to protect their day-to-day identity and our nanoparticles are no different — first finding fame for their potential use in solar panel technology.
The reason is simple. These nanoparticles are super-efficient at receiving and emitting light, which makes them great at capturing energy from the Sun. But i was also this fluorescent property, combined with their stability, that made the CLF team wonder if they could also be used in biological imaging.
In fact, it’s almost like they were designed for such a purpose. These nanoparticles absorb and emit light in a very distinctive way, which helps researchers to identify them amongst the natural glow of our cells working and communicating with one another. This could make our images of cells clearer than ever before.
X-ray vision (without the X-rays)
There is one other advantage to using these nanoparticles in fluorescent microscopy that has the CLF team particularly excited. Their ultra-small size lets them get inside cells and map where oxygen is present within the cells, which could give us an idea of what processes are happening and where.
Someday, we may also be able to use the same method to map qualities like acidity and temperature, giving us even more detail about the hidden world of cell operation.
And while all this incredible science is being investigated further by the CLF team, we may still find uses for these particles in converting solar energy. The joy of these nanoparticles, and indeed many others, is that they are so versatile in their applications.
They are just one of the many things that effortlessly cross between the disciplines of science — pushing us to reframe our thinking and explore the interconnected universe that frames the world in which we live.
If you want to delve deeper into the science you can read more here.
Story by: Megan Pritchard, CLF communications placement student
Edited by: Ben Gilliland
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