In science fiction movies, it happens all the time: A small device is briefly held against the skin of a sick crewmember and seconds later the monitor displays what ails him. This futuristic image could someday be real.
Researchers from the ETH in Zurich, Switzerland, describe a first step in this direction in the journal Angewandte Chemie: a new method of sampling living biological organisms for direct mass-spectrometric examination.
By using a beam of nitrogen, substances from the skin of a test subject can be directed into a mass spectrometer for rapid and precise analysis. Aside from rapid clinical diagnosis without blood samples, this new technique could be enlisted for research into metabolic processes, doping tests, defense against terrorism, and the inspection of foods.
In recent years, mass spectrometry has developed into an important analytical technique for biological samples. For the actual analysis, the matrix of the sample must be removed so that the desired analytes can be accurately detected. This complicated sample preparation makes routine examinations with high sample throughput difficult.
The new process developed by Renato Zenobi and his group (an advancement on their process for breath analysis as reported in Angewandte Press Release 44/06) works without needing such efforts. Instead of introducing samples into an electrospray mass spectrometer (ESI-MS) in solution, as in the usual procedure, and atomizing them with a gas, the analytes in the new process are “sucked” right off the surface. Nitrogen is blown through a small nozzle onto the sample surface, such as the skin of a test subject. When the gas strikes the surface, it takes up semivolatile substances. The gas stream is then directed right into the electrospray source of the mass spectrometer. Here it crosses a stream of charged water droplets that take up the molecules of interest and charge them. Analysis takes only seconds.
This method allows chemical “fingerprints” to be taken from human skin. For example, it is possible to detect if someone is a smoker, or if a test subject has had a cup of coffee. The researchers were able to detect traces of explosives and model substances for chemical weapons. “This new method is not technically complicated,” explains Zenobi, “ordinary electrospray mass spectrometers can quickly and easily be adapted.”
Mass screening of food could also be carried out rapidly, inexpensively, and reliably with this new technique. Frozen samples like meat or fish do not even need to be thawed. Spoiled food can be detected by a characteristic change in its molecular fingerprint.
Author: Renato Zenobi, ETH Zürich (Switzerland), http://www.zenobi.ethz.ch/zenobi.html
Title: Neutral Desorption Sampling of Living Objects for Rapid Analysis by Extractive Electrospray Ionization Mass Spectrometry
Angewandte Chemie International Edition 2007, 46, No. 40, 7591–7594, doi: 10.1002/anie.200702200
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy