The CIN2 (Research Center for Nanoscience and Nanotechnology), is a joint centre belonging to the Spanish National Council for Scientific Research (CSIC) and the Nanotechnology Catalonian Institute (ICN).
The device is based on a carbon nanotube of 1 nanometer diameter which is clamped at both ends to two electrodes. It works as an electromechanical resonator characterized by a mechanical resonance frequency as if it was a string on a guitar. When atoms are directed towards the nanotube, they hit and stick to its surface. This increases the nanotube mass, thereby reducing its resonance frequency: this slowing of the vibration is used to quantify the mass of the atoms.
At room temperature, the nanotube resonator has a resolution of 25 zeptograms (zg) but cooling the nanotube down to 5 Kelvin (268.15 degrees C below zero) the resolution improves to 1.4 zeptograms. A zeptogram equals 10 -21 grams or, which is the same, a thousandth part of one millionth of one millionth of one millionth of a gram.
A sensor of this resolution would allow the detection of tiny amounts of mass such as the mass of proteins or other molecules with atomic resolution. Also, it could be used to monitor nuclear reactions in individual atoms, or biological molecules in chemical reactions.
The researchers tested the device by measuring the mass of evaporated chromium atoms, and the performance, as explained in an article published in the journal Nanoletters, is exceptional. The other members of the team are Benjamin Lassagne and Daniel Garcia, both of CIN2, and Albert Aguasca, from the Universitat Politècnica de Catalunya.
A remaining challenge
One of the challenges of nanotechnology and nanomechanics is having a mass spectrometer working at subatomic level. The maximum resolution had been achieved with some silicon resonators (with a resolution of about 7 to zeptograms temperature of 4.2 Kelvin). Now, the work of Bachtold and co-workers has substantially increased that resolution through the use of carbon nanotubes.
The mass of a nanotube is very low, barely a few atograms (which is a millionth of one millionth of a microgram, or 10 -18 g), so that any tiny amount of added mass will be detected. In addition, the nanotubes are mechanically ultrarigid, which makes them excellent candidates to be used as mechanical resonators.
Now, the team of Bachtold is improving the measurement set up and hopes to achieve in the near future the resolution of 0.001 zg, the mass of one nucleus. The researchers will then place proteins on the nanotube and monitor the change of the mass during chemical reactions (when a hydrogen atom is released from the protein, for instance).
Nanotechnology has been advancing rapidly in the few last years. Even so, there remain many challenges ahead, and one of them is a mass spectrometer to allow work at that level, with small biological molecules or atoms.
The development of the CIN2 team has coincided in time with others of similar characteristics, both from the U.S.A. One, at the Technical University of California (Caltech) and the other at the University of California (Berkeley). Both groups have developed mass sensors based on carbon nanotubes, with minor differences between the methods used. The fact was recently highlighted in the journal Nature Nanotechnology.
Mercé Fernández | alfa
SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University
Molecule flash mob
19.01.2017 | Technische Universität Wien
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences