New technique to measure very small masses
August 20, 2010
Mass spectrometry is a technique used to identify the elements that form a compound and quantify them, as well as to elucidate the structure and properties of molecules. To this end, it employs a small sample of the material that is going to analyze, which is ionized, is accelerating and is subjected to an electromagnetic field which deviates it from its path. By measuring the deflection of the different ions, it can be deduced from what material is. In this paper the researchers have used silicon nanowires as resonators able to measure the properties of molecules that are deposited on them. Contrary to what was believed, of silicon nanowires vary in two directions in a complex way according to the characteristics of the molecule that is deposited on it. Studying this swing can determine two of the attributes of the molecule: its mass, with an accuracy of zeptogramos, and his elastic stiffness.
"This opens the door to relevant biomedical applications, since it is clear that the mechanical properties of biological systems, including proteins, play a fundamental role in various pathogenic processes such as the tumor and infective processes", says Javier Tamayo, researcher at the CSIC in the Institute of microelectronics of Madrid, who led the study.
The discovery will help develop a new generation of mass spectrometers capable of analyzing even the proteins expressed in only a few cells: "thus you may refine the search for cellular biomarkers and, therefore, develop more effective drugs", concludes Tamayo.