Optical tweezers are a rapidly growing technology, and have opened up a wide variety of research applications in recent years. The devices operate by trapping particles at the focal points of tightly focused laser beams, allowing researchers to manipulate the objects without any physical contact.
So far, optical tweezers have been used to confine objects just micrometres across – yet there is now a growing desire amongst researchers to extend the technology to nanometre-scale particles.
In new research published in EPJ E, Janine Emile and Olivier Emile at the University of Rennes, France, demonstrate a novel tweezer design, which enabled them to trap fluorescent particles just 200 nanometres across for the first time.
If made available for widespread use, nanoscale optical traps could be used for experimental procedures requiring extreme degrees of precision – including direct measurements of nanoscale forces, alterations of cell membranes, and manipulations of viruses and DNA strands.
Emile and Emile’s design was based around ‘Arago spots’: bright points of light which form in the centres of circular shadows, as light diffracts around the objects creating them. In addition, they relied on the principle of ‘total internal reflection’ – where light rays hitting a glass-liquid interface at just the right angle are perfectly reflected.
In the experiment, the duo fired a perfectly aligned laser beam onto the interface between a glass plate, and a liquid containing suspended fluorescent nanoparticles; with an opaque circular disk partially blocking its path.
Image Credit: University of Rennes, France
When covid-19 struck Europe in March 2020, hospitals were plunged into a health crisis that was still badly understood. “Doctors really didn’t have a clue how to manage these patients,” says Laure Wynants, an [...]
Pfizer found to be 88 per cent effective at preventing symptomatic disease from delta variant. Two doses of Pfizer-BioNTech or AstraZeneca-Oxford's COVID-19 vaccines are nearly as effective against the highly transmissible delta coronavirus variant [...]
South African pharmaceutical company Aspen said Monday it was releasing its first batch of African-produced COVID-19 vaccines under a licensing deal with the US giant Johnson & Johnson. The Durban-based company said the first [...]
Since the coronavirus pandemic shut down the world, scientists have clamored to develop vaccines to prevent the spread and medicines that will cure the sick. But a virus’ main goal is to replicate and [...]
The highly transmissible delta variant of SARS-CoV-2, the coronavirus causing the disease COVID-19, is now present in 124 countries and will become the dominant strain globally in the coming months as it is outcompeting [...]
Scientists have backed proposals for Covid boosters in the autumn after blood tests on hundreds of people revealed that protective antibodies can wane substantially within weeks of second vaccine shots being given. Falls in [...]
Researchers in the United States have conducted a study showing that the coronavirus disease 2019 (COVID-19) vaccines developed by Pfizer-BioNTech and Moderna generate a coordinated adaptive immune response that is capable of eliciting recall [...]
CSIRO, Australia's national science agency, played an important role in evaluating heat-tolerant COVID-19 vaccine formulations developed by the Indian Institute of Science (IISc) and biotech start-up Mynvax—against all current SARS-CoV-2 variants of concern. Published [...]
Podcast – Nanovisaging 2040 How Synergies between Nanotechnology, Nanomedicine, and AI might Benefit Humanity
Frank Boehm (NanoApps Medical Inc. Founder) in discussion with Nana Kay in a Wealth Secrets podcast. EP 19. Nanovisaging 2040. From Nana Kay: Nanovisaging 2040: How Synergies between Nanotechnology, Nanomedicine, and AI might Benefit [...]
Canada, like several other countries, has been mixing and matching COVID-19 vaccines for weeks amid safety concerns over the AstraZeneca shot. On Monday, the chief scientist at the World Health Organization (WHO) cautioned against that approach, calling [...]
Scientists have harnessed CRISPR gene-editing technology to block the replication of the novel coronavirus in human cells — an approach that could one day serve as a new treatment for COVID-19. However, the study was performed [...]
A recent study by scientists from Japanese universities has shown that the shape of cell-derived nanoparticles, known as "extracellular vesicles" (EVs), in body fluids could be a biomarker for identifying types of cancer. In [...]
An important lesson for vaccine design Australian scientists researching how our immune system responds to COVID-19 have revealed that those infected by early variants in 2020 produced sustained antibodies, however, these antibodies are not [...]
1. How COVID-19 is affecting the globe Confirmed cases of COVID-19 have passed 185 million globally, according to Johns Hopkins University. The number of confirmed deaths stands at more than 4 million. More than 3.29 [...]
The World Health Organization (WHO) has added another COVID strain to its list of coronavirus variants to keep an eye on: the COVID-19 Lambda variant. This particular variant has now spread to more than two dozen [...]