Lifeboat Foundation

A new article published in Opto-Electronic Science reviews the fundamentals and applications of optically trapped optical nanoparticles. Optical nanoparticles are one of the key elements of photonics. They not only allow optical imaging of a plethora of systems (from cells to microelectronics), but also behave as highly sensitive remote sensors.

The success of optical tweezers in isolating and manipulating individual optical nanoparticles has been recently demonstrated. This has opened the door to high-resolution, single-particle scanning and sensing.

The most relevant results in the quickly growing fields of optical trapping of individual optical nanoparticles are summarized by this article. According to different materials and their optical properties, the optical nanoparticles are classified into five families: plasmonic nanoparticles, lanthanide-doped nanoparticles, polymeric nanoparticles, semiconductor nanoparticles, and nanodiamonds. For each case, the main advances and applications have been described.

Seas, oceans, rivers, and other bodies of water on Earth have become increasingly polluted over the past decades, and this is threatening the survival of many aquatic species. This pollution takes a wide range of forms, including the proliferation of so-called micro and nano plastics.

As suggested by their name, micro and nano plastics are harmful tiny particles derived from the disintegration of plastic waste released into the water. These particles have been found to disrupt aquatic ecosystems, for instance, delaying the growth of organisms, reducing their food intake, and damaging fish habitats.

Devising effective technologies to effectively remove these tiny particles is of utmost importance, as it could help to protect endangered species and their natural environments. These technologies should be carefully designed to prevent further pollution and destruction; thus, they should be based on environmentally friendly materials.

One of ray kurzweils wonder machines are already here self assembled nanobots called foglet machines. This could allow for future avatars that people could pilot for daily life.

Colloidal magnetic nanoparticles are candidates for application in biology, medicine and nanomanufac-turing. Understanding how these particles interact collectively in fluids, especially how they assemble and aggregate under external magnetic fields, is critical for high quality, safe, and reliable deployment of these particles. Here, by applying magnetic forces that vary strongly over the same length scale as the colloidal stabilizing force and then varying this colloidal repulsion, we can trigger self-assembly of these nanoparticles into parallel line patterns on the surface of a disk drive medium. Localized within nanometers of the medium surface, this effect is strongly dependent on the ionic properties of the colloidal fluid but at a level too small to cause bulk colloidal aggregation.

The world’s coastlines harbor a largely untapped energy source: the salinity difference between seawater and freshwater. A new nanodevice can harness this difference to generate power.

A team of researchers at the University of Illinois Urbana-Champaign has reported a design for a nanofluidic device capable of converting ionic flow into usable electric power in the journal Nano Energy. The team believes that their device could be used to extract power from the natural ionic flows at seawater-freshwater boundaries.

University of Missouri researchers’ conceptual design of a nanomaterial could potentially pave the way for new uses of nanotechnology in medicine and science.

In a recent study, scientists at the University of Missouri developed a proof of concept for a nanocapsule — a microscopic container — capable of delivering a specific “payload” to a targeted location.

While beyond the scope of this study, the discovery has the potential to revolutionize the delivery of drugs, nutrients, and other chemicals in humans and plants. The power of the forward-thinking idea for this tiny delivery mechanism comes from its inventive structure, said Gary Baker, an associate professor in the Department of Chemistry and study co-author.

True to form, a “strange metal” quantum material proved strangely quiet in recent quantum noise experiments at Rice University. Published this week in Science, the measurements of quantum charge fluctuations known as “shot noise” provide the first direct evidence that electricity seems to flow through strange metals in an unusual liquidlike form that cannot be readily explained in terms of quantized packets of charge known as quasiparticles.

“The noise is greatly suppressed compared to ordinary wires,” said Rice’s Doug Natelson, the study’s corresponding author. “Maybe this is evidence that quasiparticles are not well-defined things or that they’re just not there and charge moves in more complicated ways. We have to find the right vocabulary to talk about how charge can move collectively.”

The experiments were performed on nanoscale wires of a well-studied quantum critical material with a precise 1−2−2 ratio of ytterbium, rhodium and silicon (YbRh₂Si₂). The material contains a high degree of quantum entanglement that produces temperature-dependent behavior.

Human chromosomes are long polymer chains that store genetic information. The nucleus of each cell contains the entire human genome (DNA) encoded on 46 chromosomes with a total length of about 2 meters. To fit into the microscopic cell nucleus and at the same time provide constant access to genetic information, chromosomes are folded in the nucleus in a special, predetermined way. DNA folding is an urgent task at the intersection of polymer physics and systems biology.

A few years ago, as one of the mechanisms of chromosome folding, researchers put forward a hypothesis of active extrusion of loops on chromosomes by molecular motors. Although the ability of motors to extrude DNA in vitro has been demonstrated, observing loops in a living cell experimentally is a technically very difficult, almost impossible, task.

A team of scientists from Skoltech, MIT, and other leading scientific organizations in Russia and the U.S. have presented a physical model of a polymer folded into loops. The analytical solution of this model allowed scientists to reproduce the universal features of chromosome packing based on the experimental data—the image shows the peak-dip derivative curve of the contact probability.

Biological computing machines, such as micro and nano-implants that can collect important information inside the human body, are transforming medicine. Yet, networking them for communication has proven challenging. Now, a global team, including EPFL researchers, has developed a protocol that enables a molecular network with multiple transmitters.

First, there was the Internet of Things (IoT) and now, at the interface of computer science and biology, the Internet of Bio-Nano Things (IoBNT) promises to revolutionize medicine and health care. The IoBNT refers to biosensors that collect and process data, nano-scale Labs-on-a-Chip that run medical tests inside the body, the use of bacteria to design biological nano-machines that can detect pathogens, and nano-robots that swim through the bloodstream to perform targeted drug delivery and treatment.

“Overall, this is a very, very exciting research field,” explained Assistant Professor Haitham Al Hassanieh, head of the Laboratory of Sensing and Networking Systems in EPFL’s School of Computer and Communication Sciences (IC). “With advances in bio-engineering, synthetic biology, and nanotechnology, the idea is that nano-biosensors will revolutionize medicine because they can reach places and do things that current devices or larger implants can’t,” he continued.

For decades, researchers have sought ways to precisely manipulate and identify individual molecules like DNA in liquid environments. Such capabilities could revolutionize areas ranging from disease diagnosis to drug development. However, the randomness of molecular movements in fluids has hindered progress.

Now, scientists from Shenzhen University and the Chinese University of Hong Kong report promising advances in optical tweezing techniques that allow exquisite control over nanoscale biological particles (Light: Science & Applications, “CRISPR-powered optothermal nanotweezers: Diverse bio-nanoparticle manipulation and single nucleotide identification”).

A The diagrammatic sketch of the three components in the solution: DNA@AuNS conjugate, CRISPR/Cas12a complex, and target ssDNA. b Optical setup, the BS, SPF, and TL are beam splitter, short pass filter, and tube lens (f = 200 mm), respectively. Additional details of the setup are provided in the Materials and Methods section. c Dispersion of the three components in the solution without optical heating. d Optothermal net force induced migration and DNA@AuNS conjugate cleavage upon optical heating, the heating laser power is 0.5 mW. e Observation of the cleavage after the optical heating is switched off. (© Light: Science & Applications) (click on image to enlarge)