Conventional microscopes produce enlarged images of small structures or objects with the help of light. Nanoparticles, however, are so small that they hardly absorb or scatter light and, hence, remain invisible. Optical resonators increase the interaction between light and nanoparticles: They capture light in smallest space by reflecting it thousands of times between two mirrors. In case a nanoparticle is located in the captured light field, it interacts thousands of times with the light such that the change in light intensity can be measured. “The light field has various intensities at different points in space. This allows conclusions to be drawn with respect to the position of the nanoparticle in the three-dimensional space,” says Dr. Larissa Kohler from KIT’s Physikalisches Institut.
Resonator makes movements of nanoparticles visible
And not only that: “If a nanoparticle is located in water, it collides with water molecules that move in arbitrary directions due to thermal energy. These collisions cause the nanoparticle to move randomly. This Brownian motion can now also be detected,” the experts adds. “So far, it has been impossible for an optical resonator to trackthe motion of a nanoparticle in space. It was only possible to state whether or not the particle is located in the light field,” Kohler explains. In the novel fiber-based Fabry-Pérot resonator, highly reflecting mirrors are located on the ends of glass fibers. It allows us to derive the hydrodynamic radius of the particle, that is the thickness of the water surrounding the particle, from its three-dimensional movement. This is important, because this thickness changes the properties of the nanoparticle. “As a result of the hydrate shell, it is possible to detect nanoparticles that would have been too small without it,” Kohler says. Moreover, the hydrate shell around proteins or other biological nanoparticles might have an impact on biological processes.
A potential application of the resonator may be the detection of three-dimensional motion with high temporal resolution and characterization of optical properties of biological nanoparticles, such as proteins, DNA origami, or viruses. In this way, the sensor might provide insights into not yet understood biological processes.
News
Study Shows Brain Signals Only Matter if They Arrive on Time
Signals are processed only if they reach the brain during brief receptive cycles. This timing mechanism explains how attention filters information and may inform therapies and brain-inspired technologies. It has long been recognized that [...]
Does Space-Time Really Exist?
Is time something that flows — or just an illusion? Exploring space-time as either a fixed “block universe” or a dynamic fabric reveals deeper mysteries about existence, change, and the very nature of reality. [...]
Unlocking hidden soil microbes for new antibiotics
Most bacteria cannot be cultured in the lab-and that's been bad news for medicine. Many of our frontline antibiotics originated from microbes, yet as antibiotic resistance spreads and drug pipelines run dry, the soil [...]
By working together, cells can extend their senses beyond their direct environment
The story of the princess and the pea evokes an image of a highly sensitive young royal woman so refined, she can sense a pea under a stack of mattresses. When it comes to [...]
Overworked Brain Cells May Hold the Key to Parkinson’s
Scientists at Gladstone Institutes uncovered a surprising reason why dopamine-producing neurons, crucial for smooth body movements, die in Parkinson’s disease. In mice, when these neurons were kept overactive for weeks, they began to falter, [...]
Old tires find new life: Rubber particles strengthen superhydrophobic coatings against corrosion
Development of highly robust superhydrophobic anti-corrosion coating using recycled tire rubber particles. Superhydrophobic materials offer a strategy for developing marine anti-corrosion materials due to their low solid-liquid contact area and low surface energy. However, [...]
This implant could soon allow you to read minds
Mind reading: Long a science fiction fantasy, today an increasingly concrete scientific goal. Researchers at Stanford University have succeeded in decoding internal language in real time thanks to a brain implant and artificial intelligence. [...]
A New Weapon Against Cancer: Cold Plasma Destroys Hidden Tumor Cells
Cold plasma penetrates deep into tumors and attacks cancer cells. Short-lived molecules were identified as key drivers. Scientists at the Leibniz Institute for Plasma Science and Technology (INP), working with colleagues from Greifswald University Hospital and [...]
This Common Sleep Aid May Also Protect Your Brain From Alzheimer’s
Lemborexant and similar sleep medications show potential for treating tau-related disorders, including Alzheimer’s disease. New research from Washington University School of Medicine in St. Louis shows that a commonly used sleep medication can restore normal sleep patterns and [...]
Sugar-Coated Nanoparticles Boost Cancer Drug Efficacy
A team of researchers at the University of Mississippi has discovered that coating cancer treatment carrying nanoparticles in a sugar-like material increases their treatment efficacy. They reported their findings in Advanced Healthcare Materials. Over a tenth of breast [...]
Nanoparticle-Based Vaccine Shows Promise in Fighting Cancer
In a study published in OncoImmunology, researchers from the German Cancer Research Center and Heidelberg University have created a therapeutic vaccine that mobilizes the immune system to target cancer cells. The researchers demonstrated that virus peptides combined [...]
Quantitative imaging method reveals how cells rapidly sort and transport lipids
Lipids are difficult to detect with light microscopy. Using a new chemical labeling strategy, a Dresden-based team led by André Nadler at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) and [...]
Ancient DNA reveals cause of world’s first recorded pandemic
Scientists have confirmed that the Justinian Plague, the world’s first recorded pandemic, was caused by Yersinia pestis, the same bacterium behind the Black Death. Dating back some 1,500 years and long described in historical texts but [...]
“AI Is Not Intelligent at All” – Expert Warns of Worldwide Threat to Human Dignity
Opaque AI systems risk undermining human rights and dignity. Global cooperation is needed to ensure protection. The rise of artificial intelligence (AI) has changed how people interact, but it also poses a global risk to human [...]
Nanomotors: Where Are They Now?
First introduced in 2004, nanomotors have steadily advanced from a scientific curiosity to a practical technology with wide-ranging applications. This article explores the key developments, recent innovations, and major uses of nanomotors today. A [...]
Study Finds 95% of Tested Beers Contain Toxic “Forever Chemicals”
Researchers found PFAS in 95% of tested beers, with the highest levels linked to contaminated local water sources. Per- and polyfluoroalkyl substances (PFAS), better known as forever chemicals, are gaining notoriety for their ability [...]
