Carbon nanomaterials have been hailed as potential drug carriers and biosensors, so it is important to understand how they interact with human cells. Scientists in China have studied the interaction of C₆₀ nanoparticles (NPs) with human red blood cells and found that they made the cell membrane become “softer and easier to break”. They were able to successful model this, and predict the effect of a given amount of NPs. The finding could be used to determine appropriate dosage levels of C₆₀ NPs in medical applications for maximum therapeutic effect with the minimum toxicity.

Read more about this fascinating work in this HOT PCCP article:

Mechanical characteristics of human red blood cell membrane changing due to C₆₀ nanoparticles infiltration
Yue Zheng
DOI: 10.1039/C2CP42850D

A paper from the recent PCCP themed issue on Predicting new molecules by quantum chemical methods has been highlighted in UCLA today. The article by Anastassia Alexandrova and her coworkers was featured on the back cover of the issue and describes the authors work on using computational methods to discover new inorganic clusters and understand their bonding.

Read this interesting PCCP paper today:

Selected AB₄^2−/− (A = C, Si, Ge; B = Al, Ga, In) ions: a battle between covalency and aromaticity, and prediction of square planar Si in SiIn₄^2−/−
Anastassia N. Alexandrova, Michael J. Nayhouse, Mioy T. Huynh, Jonathan L. Kuo, Arek V. Melkonian, Gerardo Chavez, Nina M. Hernando, Matthew D. Kowal and Chi-Ping Liu
DOI: 10.1039/C2CP41821E

Scientists working in Australia, Poland and the USA have come up with a combined theoretical and experimental approach for screening candidate materials that could be used to capture nerve gas agents. They conclude that the ideal material contains slit-shaped pores of around 0.5 nm width.

Their PCCP paper was highlighted on the nanowerk website. Read the article today:

Screening of Carbonaceous Nanoporous Materials for Capture of Nerve Agents
Piotr Kowalczyk, Artur Piotr Terzyk, Piotr A. Gauden and Alexander V Neimark
DOI: 10.1039/C2CP43366D

In this fascinating PCCP Perspective Alexander Ivanov and Alexander Boldyrev describe progress in using theoretical methods to predict unusual new molecules that can potentially be made for real in the experimental lab.

They suggest that emerging methods for predicting exciting materials and clusters will allow the field to develop in new directions in the coming years.

Read this PCCP Perspective article in full today:

Reliable predictions of unusual molecules
Alexander S. Ivanov and Alexander I. Boldyrev
DOI: 10.1039/C2CP42877F

If you enjoyed this article you may also be interested in our recent themed issue on Predicting new molecules by quantum chemical methods, Guest Edited by Gabriel Merino and Thomas Heine.

Single molecule fluorescence measurements hold great promise for studying biological processes on a very small scale. These experiments are typically conducted using a scanning confocal fluorescence microscope.

The data rely on the focusing of excitation light to a specific point on a molecule, with the fluorescence output being collected using the same objective lens. The fluorescence output can be varied by changing the external electric field. But an out-of-focus excitation light, say scientists in Singapore, due to the not uncommon occurrence of damage to the type of thin film devices used in such experiments, can result in a decrease in the output fluorescence – which could potentially be misinterpreted as a significant effect.

The results indicate that researchers measuring fluorescence modulation using this electric field method should be aware that this type of artefact could interfere with their results.

Read more details about these interesting findings:

Other origins for the fluorescence modulation of single dye molecules in open-circuit and short-circuit devices
Edwin Yeow, Jefri Sanusi Teguh, Michael Kurniawan, Xiangyang Wu and Tze Chien Sum
DOI: 10.1039/C2CP43284F

Scientists in France and Germany have come up with a method to model the electronic and magnetic properties of polynuclear complexes. Electron paramagnetic resonance (EPR) spectroscopy is used to measure magnetic anisotropy, but in weakly coupled systems, the signal can be very complicated or absent altogether.

Older methods using a spin ladder approach were only accurate at the lowest temperatures. The new method allowed the team to interpret complex experimental EPR data at various temperatures.

Such complexes are important in molecular magnets and are found in nature, so their study is of wide interest.

Read this HOT PCCP article today:

A combined high-field EPR and quantum chemical study on a weakly ferromagnetically coupled dinuclear Mn(III) complex. A complete analysis of the EPR spectrum beyond the strong coupling limit.
Marius Retegan, Marie-Noëlle Collomb, Frank Neese and Carole Duboc
DOI: 10.1039/C2CP42955A

US scientists have studied spin Hall and Klein tunnelling effects during oxidation of graphene and few-layer graphene. Previous studies had suggested that the reductive properties of graphene change depending on the external magnetic field, with explosive redox reactions between graphene and strong oxidants accelerating following temperature reduction from 22 to 16 °C.

A typical way to oxidise graphene to oxide is to use a mixture of sulfuric acid, NaNO₃ and KMnO₄ (Hummers method). The Na⁺ and K⁺ ions of KMnO₄ /NaNO₃ have until now been assumed not to influence the redox reactions involved. This work shows that changing the cations has a big effect: replacing Na⁺ and K⁺ with Mg²⁺ and Ca²⁺, the team observed faster, more electronically delocalised complete oxidation to CO₂ at temperatures between 16 and 21 °C. With Na⁺ and K⁺, they saw faster, more electronically localised oxidation to CO at temperatures >22 °C. These observations are attributed to the spin Hall effect (SHE) for the Na⁺ and K⁺ ions and Klein tunnelling effect for the Mg²⁺ and Ca²⁺ ions.

The observations will be very helpful in aiding understanding of the correlation between the structure and the properties of layered materials, such as graphene and boron nitride. The observed SHE gives an explanation of recently reported tunnelling of graphene electrons through boron nitride.

Read the full details of this fascinating PCCP article today:

Nuclear spin Hall and Klein tunneling effects during oxidation with electric and magnetic field inductions in graphene
Reginald B. Little, Felicia McClary, Bria Rice, Corine Jackman and James W. Mitchell
DOI: 10.1039/C2CP43276E

In this HOT PCCP Perspective Prof. Richard Van Duyne and coworkers describe the contribution of hot spots to the enhancement of signals observed in surface enhanced Raman spectroscopy (SERS), including techniques for creating and controlling these hot spots.

Read this fascinating PCCP Perspective in full today:

Creating, characterizing, and controlling chemistry with SERS hot spots
Samuel L. Kleinman, Renee R. Frontiera, Anne-Isabelle Henry, Jon A. Dieringer and Richard P. Van Duyne
DOI: 10.1039/C2CP42598J

Professor Van Duyne is co-Guest Editor of our upcoming themed issue on Plasmonics and Spectroscopy.

Submit an article for this exciting issue by 1st November 2012 .