Controlling strong electromagnetic fields on nanoparticles is the key to triggering targeted molecular reactions on their surfaces. Such control over strong fields is achieved via laser light. Although laser-induced formation and breaking of molecular bonds on nanoparticle surfaces have been observed in the past, nanoscopic optical control of surface reactions has not yet been achieved. | |
An international team led by Dr. Boris Bergues and Prof. Matthias Kling at Ludwig-Maximilians-Universität (LMU) and the Max Planck Institute of Quantum Optics (MPQ) in collaboration with Stanford University has now closed this gap. The physicists determined for the first time the location of light-induced molecular reactions on the surface of isolated silicon dioxide nanoparticles using ultrashort laser pulses (Optica, “All-optical nanoscopic spatial control of molecular reaction yields on nanoparticles”). |
There is hustle and bustle on the surface of nanoparticles. Molecules dock, dissolve and change their location. All this drives chemical reactions, changes matter and even gives rise to new materials. The events in the nanocosmos can be controlled with the help of electromagnetic fields. | |
This has now been demonstrated by a team led by Dr. Boris Bergues and Prof. Matthias Kling from the Ultrafast Electronics and Nanophotonics Group. To this end, the researchers used strong, femtosecond-laser pulses to generate localized fields on the surfaces of isolated nanoparticles. A femtosecond is one millionth of a billionth of a second. | |
Using so-called reaction nanoscopy, a new technique recently developed in the same group, the physicists were able to image the reaction site and birthplace of molecular fragments on the surface of silica nanoparticles – at a resolution better than 20 nanometers. | |
The nanoscopic spatial control, achievable at even higher resolution, was brought about by the scientists by superimposing the fields of two laser pulses with different color, and controlled waveform and polarization. Thereby, they had to set the time delay between the two pulses with attosecond accuracy. An attosecond is still a thousand times shorter than a femtosecond. When interacting with this tailored light, the surface of the nanoparticles and the molecules adsorbed there were ionized at targeted sites, leading to the dissociation of the molecules into different fragments. | |
“Molecular surface reactions on nanoparticles play a fundamental role in nanocatalysis. They could be a key to clean energy production, in particular via photocatalytic water splitting,” explains Matthias Kling. “Our results also pave the way for tracking photocatalytic reactions on nanoparticles not only with nanometer spatial resolution, but also with femtosecond temporal resolution. This will provide detailed insights into the surface processes on the natural spatial and temporal scales of their dynamics,” adds Boris Bergues. | |
The scientists anticipate that this promising new approach can be applied to numerous complex isolated nanostructured materials. |

News
Johns Hopkins Researchers Uncover a New Way To Kill Cancer Cells
A new study reveals that blocking ribosomal RNA production rewires cancer cell behavior and could help treat genetically unstable tumors. Researchers at the Johns Hopkins Kimmel Cancer Center and the Department of Radiation Oncology and Molecular [...]
AI matches doctors in mapping lung tumors for radiation therapy
In radiation therapy, precision can save lives. Oncologists must carefully map the size and location of a tumor before delivering high-dose radiation to destroy cancer cells while sparing healthy tissue. But this process, called [...]
Scientists Finally “See” Key Protein That Controls Inflammation
Researchers used advanced microscopy to uncover important protein structures. For the first time, two important protein structures in the human body are being visualized, thanks in part to cutting-edge technology at the University of [...]
AI tool detects 9 types of dementia from a single brain scan
Mayo Clinic researchers have developed a new artificial intelligence (AI) tool that helps clinicians identify brain activity patterns linked to nine types of dementia, including Alzheimer's disease, using a single, widely available scan—a transformative [...]
Is plastic packaging putting more than just food on your plate?
New research reveals that common food packaging and utensils can shed microscopic plastics into our food, prompting urgent calls for stricter testing and updated regulations to protect public health. Beyond microplastics: The analysis intentionally [...]
Aging Spreads Through the Bloodstream
Summary: New research reveals that aging isn’t just a local cellular process—it can spread throughout the body via the bloodstream. A redox-sensitive protein called ReHMGB1, secreted by senescent cells, was found to trigger aging features [...]
AI and nanomedicine find rare biomarkers for prostrate cancer and atherosclerosis
Imagine a stadium packed with 75,000 fans, all wearing green and white jerseys—except one person in a solid green shirt. Finding that person would be tough. That's how hard it is for scientists to [...]
Are Pesticides Breeding the Next Pandemic? Experts Warn of Fungal Superbugs
Fungicides used in agriculture have been linked to an increase in resistance to antifungal drugs in both humans and animals. Fungal infections are on the rise, and two UC Davis infectious disease experts, Dr. George Thompson [...]
Scientists Crack the 500-Million-Year-Old Code That Controls Your Immune System
A collaborative team from Penn Medicine and Penn Engineering has uncovered the mathematical principles behind a 500-million-year-old protein network that determines whether foreign materials are recognized as friend or foe. How does your body [...]
Team discovers how tiny parts of cells stay organized, new insights for blocking cancer growth
A team of international researchers led by scientists at City of Hope provides the most thorough account yet of an elusive target for cancer treatment. Published in Science Advances, the study suggests a complex signaling [...]
Nanomaterials in Ophthalmology: A Review
Eye diseases are becoming more common. In 2020, over 250 million people had mild vision problems, and 295 million experienced moderate to severe ocular conditions. In response, researchers are turning to nanotechnology and nanomaterials—tools that are transforming [...]
Natural Plant Extract Removes up to 90% of Microplastics From Water
Researchers found that natural polymers derived from okra and fenugreek are highly effective at removing microplastics from water. The same sticky substances that make okra slimy and give fenugreek its gel-like texture could help [...]
Instant coffee may damage your eyes, genetic study finds
A new genetic study shows that just one extra cup of instant coffee a day could significantly increase your risk of developing dry AMD, shedding fresh light on how our daily beverage choices may [...]
Nanoneedle patch offers painless alternative to traditional cancer biopsies
A patch containing tens of millions of microscopic nanoneedles could soon replace traditional biopsies, scientists have found. The patch offers a painless and less invasive alternative for millions of patients worldwide who undergo biopsies [...]
Small antibodies provide broad protection against SARS coronaviruses
Scientists have discovered a unique class of small antibodies that are strongly protective against a wide range of SARS coronaviruses, including SARS-CoV-1 and numerous early and recent SARS-CoV-2 variants. The unique antibodies target an [...]
Controlling This One Molecule Could Halt Alzheimer’s in Its Tracks
New research identifies the immune molecule STING as a driver of brain damage in Alzheimer’s. A new approach to Alzheimer’s disease has led to an exciting discovery that could help stop the devastating cognitive decline [...]