A team of researchers from the Max Planck Institute for the Science of Light and Friedrich-Alexander University Erlangen has found a way to prove a theory suggesting the possibility of cloaking a nanoparticle using a single molecule—by nearly doing it with a gold nanoparticle and a dibenzoterrylene molecule. In their paper published in the journal Physical Review Letters, the group describes their experiments with coupled nanoparticles and molecules, and what they learned from them.

For several years, scientists have been experimenting with coupling nanoparticles and molecules. In most such work, the nanoparticle (which is generally larger than the molecule) serves as an antenna of sorts, funneling light to the molecule. The goal has been to boost the emissions from the molecule or to absorb the light they receive—both of which can be used to detect biomolecules under certain circumstances. In other work, researchers have looked into the possibility of controlling the emissions coming from the molecule to match the wavelength of the incoming light. In theory, if they are in phase, the nanoparticle’s shadow should dissipate or disappear completely—a form of cloaking. In this new effort, the researchers sought to prove this theory by carrying out experiments with nanoparticles and molecules.

The work involved first getting a130-nm-wide gold nanoparticle to couple with a dibenzoterrylene molecule. This involved placing several of the gold nanoparticles on a surface and then covering them with a solution containing dibenzoterrylene molecules. The setup was then chilled to the point that the solution solidified. The team then used a laser to look for a test nanoparticle-molecule pairing until they found a pair that had closely coupled. They then focused a near-infrared beam on the pair, from the direction of the molecule.

Electroluminescence (EL), electrically produced luminescence, is crucial to the operation of many electronic devices that are designed to emit light. EL can theoretically be achieved in devices with a variety of structures and made of different materials. However, to be electroluminescent, these devices need to have a number of core features that allow them to support specific light-emitting materials.

These core features have so far limited the range of materials that can be used to build electroluminescent devices. This ultimately prevented the development of devices that can emit light at a wide range of wavelengths.

Researchers at University of California Berkeley (UC Berkeley) have recently realized an electroluminescent device that can emit light from infrared to ultraviolet wavelengths. This new device, presented in a paper published in Nature Electronics, was built using carbon nanotubes (CNTs), large, cylindrical carbon-based structures that are often used to fabricate electronics.

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Researchers have discovered how a protein in plant roots controls the uptake of minerals and water, a finding which could improve the tolerance of agricultural crops to climate change and reduce the need for chemical fertilizers.

The research, published in Current Biology, shows that members of the blue copper proteins family, the Uclacyanins are vital in the formation of Casparian strips. These strips are essential structures that control mineral nutrient and water use efficiencies by forming tight seals between cells in plants, blocking nutrients and water leaking between.

This is the first evidence showing the implications of this family in the biosynthesis of lignin, one of the most abundant organic polymers on earth. This study reveals that the molecular machinery required for Casparian strip lignin deposition is highly ordered by forming nano-domains which can have a huge impact on plant nutrition, a finding that could help in the development of crops that are efficient in taking in the nutrients they need.

Methods: In this review, due to their promise, we focus on inorganic nanomaterials [such as hollow mesoporous silica nanoparticles (HMSNs), tungsten sulfide quantum dots (WS2QDs), and gold nanorods (AuNRs)] combining PTT with CHT, RT or IT in one treatment, aiming to provide a comprehensive understanding of PTT-based combinational cancer therapy. Results: This review found much evidence for the use of inorganic nanoparticles for PTT-based combinational cancer therapy. Conclusion: Under synergistic effects, inorganic nanomaterial-based combinational treatments exhibit enhanced therapeutic effects compared to PTT, CHT, RT, IT or PDT alone and should be further investigated in the cancer field.

Applications of inorganic nanomaterials in photothermal therapy based on combinational cancer treatment — pubmed.

Low-temperature plasmas offer promise for applications in medicine, water purification, agriculture, pollutant removal, nanomaterial synthesis and more. Yet making these plasmas by conventional methods takes several thousand volts of electricity, says David Go, an aerospace and mechanical engineer at the University of Notre Dame. That limits their use outside high-voltage power settings.

In work supported by the U.S. National Science Foundation, Go and a team of researchers conducted research that explores making plasma devices that can be operated without electrical power—they need only human or mechanical energy.

Their paper in Applied Physics Letters introduces a strategy the scientists call “energy-conversion plasma” as an alternative to producing “transient spark” discharges without the need for a very high-voltage power supply.

“Eat your vitamins” might be replaced with “ingest your ceramic nano-particles” in the future as space research is giving more weight to the idea that nanoscopic particles could help protect cells from common causes of damage.

Oxidative stress occurs in our bodies when cells lose the natural balance of electrons in the molecules that we are made of. This is a common and constant occurrence that is part of our metabolism but also plays a role in the aging process and several pathological conditions, such as heart failure, muscle atrophy and Parkinson’s disease.

The best advice for keeping your body in balance and avoiding oxidative stress is still to have a healthy diet and eat enough vitamins, but nanoparticles are showing promising results in keeping cells in shape.

Melittin (MEL), a major peptide component of bee venom, is an attractive candidate for cancer therapy. This agent has shown a variety of anti-cancer effects in preclinical cell culture and animal model systems. Despite a convincing efficacy data against variety of cancers, its applicability to humans has met with challenges due to several issues including its non-specific cytotoxicity, degradation and hemolytic activity. Several optimization approaches including utilization of nanoparticle based delivery of MEL have been utilized to circumvent the issues. Here, we summarize the current understanding of the anticancer effects of bee venom and MEL on different kinds of cancers. Further, we also present the available information for the possible mechanism of action of bee venom and/or MEL.

Keywords: Bee venom, Melittin, Melittin conjugates, Cancer management, Anti-cancer effects.

Cancer is one of the major ailment effecting humankind and remains as one of the leading causes of mortality worldwide. The current available data suggests that over 10 million new patients are diagnosed with the disease every year and over 6 million deaths are associated with it representing roughly 12% of worldwide deaths. Fifteen million new cancer cases are anticipated to be diagnosed in the year 2020 [1] which will potentially increase to over 20 million by 2025 [2] and more in years to come. It is also anticipated that the growth and aging of the population may increase the new cancer cases to 21.7 million with about 13 million cancer deaths by the year 2030 [3].

Antibiotic resistance is a global human health threat, causing routine treatments of bacterial infections to become increasingly difficult. The problem is exacerbated by biofilm formation by bacterial pathogens on the surfaces of indwelling medical and dental devices that facilitate high levels of tolerance to antibiotics. The development of new antibacterial nanostructured surfaces shows excellent prospects for application in medicine as next-generation biomaterials. The physico-mechanical interactions between these nanostructured surfaces and bacteria lead to bacterial killing or prevention of bacterial attachment and subsequent biofilm formation, and thus are promising in circumventing bacterial infections. This Review explores the impact of surface roughness on the nanoscale in preventing bacterial colonization of synthetic materials and categorizes the different mechanisms by which various surface nanopatterns exert the necessary physico-mechanical forces on the bacterial cell membrane that will ultimately result in cell death.

Nature has spent millennia honing the virus into a ruthlessly efficient delivery vehicle for nucleic acids. Viruses have even been harnessed for our own delivery purposes. But some applications have had only mixed success. For example, commercial applications of genetic engineering, which require high scalability, low cost, and impeccable safety, remain a challenge.

Although they can easily enter the body and inject their payload into cells, viruses may stimulate a dangerous immune reaction and cause long-term medical complications. In addition, viruses can be expensive and time consuming to cultivate.

Safer and more practical alternatives to viruses are being sought by innovative companies. For example, these companies are developing nonviral gene delivery systems that incorporate nanoparticle formulations, ultrasound, and electric fields. These systems can slip bits of genetic material into cells efficiently and cost-effectively in a range of applications.