Nav: Home

Research paves the way for next generation of optical tweezers

March 14, 2019

Scientists have developed a pioneering new technique that could pave the way for the next generation of optical tweezers.

A team of researchers from the Universities of Glasgow, Bristol and Exeter, have created a new method of moving microscopic objects around using micro-robotics.

Currently, optical tweezers - which are used to study proteins, biological molecular motors, DNA and the inner life of cells - use light to hold objects as small as a single nanoparticle in one place.

They use the unusual optical forces created by tightly focused laser beams to trap and manipulate particles, essentially acting as 'microscopic hands' for scientists.

The first optical tweezers were developed in the 1970s by Dr Arthur Ashkin. Since then, a series of breakthroughs have allowed scientists to manipulate complex objects such as viruses and cells. Dr Ashkin, now in his 90s, was recently awarded the Nobel Prize in Physics in 2018 for his pioneering work.

However, this existing technique has limitations - the high intensities of light required by optical tweezers can damage live biological specimens, and also restrict the types of objects that can be held.

Now, the research team have developed a new technique that enables optical trapping without focussing any laser light onto the trapped particles.

To do this they have developed optically trapped micro-rotors, which are placed in the liquid surrounding the particle, and used to manipulate its movement using fluid flow.

As the micro-rotors are rotated, they create a wave in the liquid that exerts a force on the particle - much in the same way that a jet of water in a Jacuzzi can push away anything that floats past.

By controlling the directions of each micro-rotor, scientists can either move the particle to a specific location or hold it in one spot - allowing particles to be sorted or imaged at high resolution.

Crucially, this new technique allows scientists to use flow to pinpoint one specific particle at a time, and not affect others in close proximity.

The research is published in the leading journal Nature Communications.

Dr Phillips, part of the University of Exeter's Physics department, and senior author on the study said: "This research expands the applications of optical tweezers to trap particles of any material in a liquid environment, and without risk of photo-damage, and adds to the toolbox of techniques that allow us develop new nanotechnologies."
"Indirect optical trapping using light driven micro-rotors for reconfigurable hydrodynamic manipulation" is published in Nature Communications on Thursday, March 14 2019.

University of Exeter

Related Physics Articles:

Diamonds coupled using quantum physics
Researchers at TU Wien have succeeded in coupling the specific defects in two such diamonds with one another.
The physics of wealth inequality
A Duke engineering professor has proposed an explanation for why the income disparity in America between the rich and poor continues to grow.
Physics can predict wealth inequality
The 2016 election year highlighted the growing problem of wealth inequality and finding ways to help the people who are falling behind.
Physics: Toward a practical nuclear pendulum
Researchers from Ludwig-Maximilians-Universitaet (LMU) Munich have, for the first time, measured the lifetime of an excited state in the nucleus of an unstable element.
Flowers use physics to attract pollinators
A new review indicates that flowers may be able to manipulate the laws of physics, by playing with light, using mechanical tricks, and harnessing electrostatic forces to attract pollinators.
Physics, photosynthesis and solar cells
A University of California, Riverside assistant professor has combined photosynthesis and physics to make a key discovery that could help make solar cells more efficient.
2-D physics
Physicist Andrea Young receives a 2016 Packard Fellowship to pursue his studies of van der Waals heterostructures.
Cats seem to grasp the laws of physics
Cats understand the principle of cause and effect as well as some elements of physics.
Plasma physics' giant leap
For the first time, scientists are looking at real data -- not computer models, but direct observation -- about what is happening in the fascinating region where the Earth's magnetic field breaks and then joins with the interplanetary magnetic field.
Nuclear physics' interdisciplinary progress
The theoretical view of the structure of the atom nucleus is not carved in stone.

Related Physics Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Climate Crisis
There's no greater threat to humanity than climate change. What can we do to stop the worst consequences? This hour, TED speakers explore how we can save our planet and whether we can do it in time. Guests include climate activist Greta Thunberg, chemical engineer Jennifer Wilcox, research scientist Sean Davis, food innovator Bruce Friedrich, and psychologist Per Espen Stoknes.
Now Playing: Science for the People

#527 Honey I CRISPR'd the Kids
This week we're coming to you from Awesome Con in Washington, D.C. There, host Bethany Brookshire led a panel of three amazing guests to talk about the promise and perils of CRISPR, and what happens now that CRISPR babies have (maybe?) been born. Featuring science writer Tina Saey, molecular biologist Anne Simon, and bioethicist Alan Regenberg. A Nobel Prize winner argues banning CRISPR babies won’t work Geneticists push for a 5-year global ban on gene-edited babies A CRISPR spin-off causes unintended typos in DNA News of the first gene-edited babies ignited a firestorm The researcher who created CRISPR twins defends...