Long live the Nucleobase!

Multiple medical and biological sensors and targeted drug delivery are based in the functionalization of nanoparticles (NPs) with biomolecules. The role of the NPs is to enhance the optical response of the target surroundings. But this enhancement comes with a huge risk: this same radiation can severily damage DNA or RNA producing mutations.

Johannes Feist (UAM) together with groups from the University of Modena and the University of Munich, have studied in which conditions these NPs can act as a protection for the biomolecules (in this case Uracil) while being effective in their sensing/therapeutic function. And importantly, the results proposed in their research can be easily implemented with the current nanophotonic technology.

This paper, published in the Journal of Physical Chemistry Letters, has been recognized with the cover we designed together with the supervision of Dr. Feist.

Optoelectronics: MoS2 on canvas.

If I understand it correctly (and I’m probably not), Andres Castellanos is not only making interesting discoveries in condensed matter physics. He and his collaborators (Kavli Institute of Nanoscience and the University of Teheran) are also actively working on making it easier for others to make advances on this area. How? By making easier to use, cheaper technology.

A good example is their “under 100 bucks probe station”. Another one is this recent paper where they fabricate paper-supported semiconducting devices by painting on them with MoS2 crystal. Let me repeat this last statement: BY PAINTING ON THEM WITH MoS2. They’ve not only proved this methodology works and produces perfectly working devices. They also show how this approach could open the path for the construction of cheaper sensors.

The picture we did for them to illustrate this process has been featured in the cover of Nanoscale.

Hedgehog spin textures

Magnetic skirmions are quasiparticles which present extended configurations (or textures) of spins and their physics are of great interest since they could be used in spintronics as sensors or memory storage devices. Its manipulation and tailoring is thus of great importance.

In a recent work published in Nanoscale, a group led by Prof. Agustina Asenjo, report the stabilization of half hedgehog skyrmionic configuration in permalloy hemispherical nanodots, induced by the stray field of the MFM probe.

As the first author, Eider Berganza, explains, “this is a remarkable achievement due to soft magnetic nature of the permalloy and the absence of the choice of the material, which does not present magnetocrystalline anisotropy or Dzyaloshinskii–Moriya interaction, considered as necessary ingredients for the nucleation of skyrmions”.

 

This research, has been a huge collaborative effort that involved sample preparation, measurements and theoretical micromagnetic simulations in Spain, Germany and the US.

This image we did under the supervision of Eider Berganza and Miriam Jaafar (ICMM-CSIC) has been featured in the Cover of Nanoscale. Personally, has been the apex of a long and beautiful collaboration with old friends.

 

Topographic reconstruction

With today’s free tools and open information (satellite images, topography, etc) it is pretty straightforward to reconstruct real places and to present geographical information. Just an example:

Polariton condensates’ propagation.

Polaritons are versatile quasiparticles that could be at the core of new technologies, since polariton devices have been proposed, such as polariton lasers, optical gates, transistors, spin-based elements and integrated circuits. Yet, their propagation depends strongly on the geometry of the pathway laid for them.

In a recent paper, Luis Viña, Dolores MartĂ­n, et al. in a huge collaborative research (Madrid, Jena, WĂŒrzburg, Saint-Petersburg, Reykjavik and Saint Andrews) have analyzed the Impact of the energetic landscape on polariton condensates’ propagation along a coupler”, published in Advanced Optical Materials.



The amount of technical challenges involved in this research is hard to grasp: from the manufacture of the guides to the experimental measurements, that require literally “taking pictures of light”.

We did this picture that was featured in the cover of Advanced Optical Materials, under close supervision of Dolores Martín and Luis Viña.

 

Vision evolution

This is an old side project we started three years ago and it is finally released… or recover… I’m not sure.

It is an explanation of how the eye evolved from very primitive and simple structures to the magnificent piece of machinery that it is today. And how it evolved independently in different species.

Finally, I have to thank Natalia Ruiz Zelmanovitch for the voice over, and Javier Trapiella and Montse Daura for their ideas and advices. Hope you like it!

 

Sound Vortices

At Phonometa (Christensen’s Research Group), they’re specialists in physical acoustics and they’re finding acoustic analogues to an amount of physical processes.

In their last published work they show that, in Dr. Christensen own words “a Majorana‐like bound state can be engineered in artificial acoustic lattices thanks to a Jackiw–Rossi vortex, which is the analog of a topological superconductor vortex. Such vortex is created by introducing a KekulĂ© texture to the man‐made lattice of rigid cylinders. We also show how this binding mechanism can be well explained by a topological pumping process comprising adiabatic variations of the cylinder radii, which concentrates strong acoustic energy to the lattice center as shown in the cover image”.

This picture we made to illustrate the process, and under close collaboration with Dr. Johan Christensen and Dr Penglin Gao, was featured in the front cover of Advanced Quantum Technologies.

Living electric wires

Materials scientists have for decades fantasized about using DNA as a structural element in electronic circuits. And for decades, the electrical properties of DNA have remain a mystery. Hundreds of different, controversial results have appeared in the literature… That ends today!

Researchers from Jerusalem, Tel Aviv, Michigan, Cyprus, Seville and Madrid, have reported the observation of “very high currents of tens of nanoamperes” through the backbone of DNA molecules. And what it is more interesting, this conduction occurs through great distances.

This observation has required the development of several techniques: a way to “grow” DNA attached to a gold nanoparticle and a way to trap this DNA using non uniform electric fields. In fact, these techniques are important on their own and whey could be the base for the development of a novel electronic bio sensor, highly sensitive to specific sequences of DNA of RNA.

We made this picture for Prof. Juan Carlos Cuevas (UAM) to illustrate these results published in Nature Nanotechnology.

 

Covalent organic frameworks

Covalent organic networks are usually synthesized on noble metal surfaces. It is widely understood that these metals have strong catalytic abilities. However, it is of great interest the use of nonmetallic surfaces in these kind of reactions.

At the NanoPhysics Lab (CMF, Gipuzkoa) they’re studying one of these routes to obtain covalent molecular systems on non-metallic substrates. In particular they’ve managed to understand and improve the synthesis of nanoribbons on TiO2 surfaces. They show that highly reduced surfaces (in opposition to stoichiometric TiO2) increases the reaction yield and improved polymer length.

We did this picture to artistically illustrate the process under the close supervision of Dr. Celia Rogero.

Graphene Design

The level of control chemistry is reaching in the synthesis of graphene is mind-blowing. At the Department of Physics in Basel University, together with the University of Bern, Warwick and Lancaster, nitrogen-doped porous graphene nanoribbons (N-GNRs) were synthesized for the first time.

These N-GNRs are ladder-like molecules whose crystal lattice contains both periodic pores and a regular pattern of nitrogen atoms. And interestingly, these molecules don’t behave as conductors, as graphene does, but as semiconductors, making them very attractive in electronic applications.

We did this picture to illustrate the synthesis of the N-GNRs on request of Prof. E. Meyer and under the close supervision of Dr. Shi-Xia Liu.