Researchers from the Basque CIC biomaGUNE center successfully deposited gold atoms on the gold nanocylinders, thus forming a chiral almost helical structure. This gives it the ability to interact with a polarized light, and the technology can be applied in optics, catalysis, biological detection and biomedical imaging.
Researchers from Biomaterials Cooperative Research Center CIC biomaGUNE Developed under the guidance of Professor Ikerbasque Luis Liz MarzánThis is a mechanism that deposits gold atoms on the previously formed gold nanocylinders through chemical reduction, thereby obtaining a quasi-helical structure in a strange screw shape.
The particles are thus obtained Chirality, The properties of the object cannot be superimposed with its mirror image and many applications.The technology, the details of which have been published in the magazine scienceIt has a wide range of uses, can reproduce other metals, and can be extended to produce nanoparticles with high chirality and optical activity.
Specifically, this geometry allows “Nano TornadoThe interaction with circularly polarized light is much more effective than the interaction with any other object. This progress may lead to the detection of biomolecules in a very selective and sensitive manner, for example in biology or medicine.
In many areas The interaction between light and matter Used for substance detection. Basically, light impact is important, and depending on the size and geometry of the particles and the type of incident light, light is absorbed or reflected very selectively.
“In a known Nanoplasmid, We use precious metal nanoparticles such as gold and silver because light interacts with this type of particle in a special way in these dimensions,” LizMarzán explained.” In this case, we studied these gold nanoparticles Chiral molecules and light with circular polarization”.
Interaction with circularly polarized light
Generally, light is unpolarized, that is, waves actually propagate in any direction within the beam.The professor continued: “However, when it is polarized, it will only propagate in one direction, and if it is circular, it will rotate clockwise or counterclockwise.” Chiral substances can preferentially absorb from Circular polarization Relative to “” OK.
Chirality is a phenomenon that occurs on all scales: chiral objects and their mirror images cannot be superimposed, whether it is our two hands or biological molecules. In this case, the chirality of “nanotcrews” gives it a unique ability to interact with circularly polarized light.
LizMarzán said: “The particle itself has a chiral geometry. This new strategy is based on a supramolecular chemical mechanism, that is, a structure in which molecules associate with each other without forming a chemical bond.”
Professor, too CIBER in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Pointed out “This means starting to control the structure of matter at the nanoscale, but within the same nanoparticle; that is, it is about 3D manufacturing on nano-objects. It is almost necessary to decide where they must be placed atom by atom to obtain a truly complex structure.”
In order to make these nanoparticles grow, “experts clearly stated, “The initial cylinder is surrounded by soap or surfactant molecules, and between them we put molecular chiral additives, so supramolecular interactions cause them to be in the metal The surface of the cylinder has a certain structure. An approximate spiral structure, which in turn guides the growth of metals with the same structure, gives it the chirality we want. As a result, so far, we have obtained the highest efficiency of circularly polarized light spectrum detection.”
Liz Marzán confirmed that the process can be extended to other types of materials: “We have observed that using the same strategy, platinum atoms can be deposited on gold nanocylinders with the same spiral structure. This opens up many possibilities for both parties. Application of optical properties Like everyone else Catalytic field (Platinum is a very effective catalyst).It can also greatly improve what may have Biological and therapeutic implications“.
Similarly, the mechanism can be applied to new Biomedical imaging technologyFor Sensor manufacturing, and many more. The author is convinced that this work will open up many avenues for other researchers due to the universality of the mechanisms that can be used with many different molecules.
The research was developed and coordinated by CIC biomaGUNE, but they got other institutions (e.g. Complutense University of Madrid (Calculation, calculation and modeling of the colloidal medium for making “nanowires”, and demonstrate how to form a colloidal medium by mixing two types of surfactants), University of Vigo with University of Extremadura (Theoretical calculation of particle optical properties) and University of Antwerp In Belgium (3D electron microscope imaging and animation reconstruction of artificial particles).
The scientific director of CIC biomaGUNE and Professor Ikerbasque Luis Liz Marzán are in one of the laboratories of the research center. / Elhuyar Komunikazioa
Guillermo González-Rubio, Jesus Mosquera, Vished Kumar, Adrián Pedrazo-Tardajos, Pablo Llombart, Diego M. Solís, Ivan Lobato, Eva G.Noya, Andrés Guerrero-Martínez, José M. Like (Luis M. Liz-Marzán). “Directional chiral seed growth of micelles on anisotropic gold nanocrystals”. scienceJune 2020. DOI: 10.1126/science.aba0980