Navigation Links
New method reveals substances on surfaces of any kind
Date:9/7/2007

Last August German police discovered about 50 tons of rotten meat on the premises of a wholesaler in Bavaria. Because the risk of rotten meat turning up in grocery stores everywhere is not to be underestimated, the importance of efficient food quality monitoring is clear.

However, reliable measurement methods that enable large numbers of samples to be analysed quickly and economically would need to be in place in order to make comprehensive monitoring a reality. In the latest issue of the scientific journal Angewandte Chemie, the group led by Renato Zenobi, Professor of Analytical Chemistry at the Organic Chemis-try Laboratory of ETH Zurich, has presented a method that successfully meets these requirements.

Based on a standard instrument

The new procedure of analysis represents a further development of the method recently published by the group in which the researchers successfully detected various substances in the breath in a simple manner. Using their enhanced method, they can now also very precisely track down substances on surfaces of any kind. Both methods are based on what is called a quadrupole time-of-flight mass spectrometer (QTOF mass spectrometer). Zenobi explains that such measuring instruments are routinely used in many areas nowadays. Samples for QTOF mass spectrometry are normally presented in solution. The solution is electrosprayed, with the additional aid of a desolvation gas. The tiny droplets give rise to ions that are characteristic of the substance to be analysed and which the QTOF instrument measures.

The ETH Zurich researchers have now almost turned the principle on its head: instead of studying the substances in the solution, they now examine the sub-stances present in the desolvation gas assisting the spray. With the newly-developed method nitrogen is blown from a small nozzle onto a sample surface. As the gas strikes the surface it desorbs semi-volatile substances. The en-riched gas stream is then fed into the mass spectrometer where the absorbed substances can be precisely analysed.

Equipment modification in less than an hour

Professor Zenobi says There is nothing special about the new method from a technical viewpoint. Huanwen Chen, who has developed the method during his post-doctoral studies in Zenobis group, impressively demonstrated this when together with his supervisor he presented the new method to a company. Within one hour Chen had modified their mass spectrometer so that it could be used to analyse the surface of any kind of object.

However, the remarkable aspect of the new method is the wide variety of possi-bilities it opens up. One particular strength of our approach is that even the surfaces of living organisms can be examined. It only takes a few seconds to measure a single sample; so large numbers of random samples can be routinely analysed, Zenobi says. For meat samples the scientists were also able to show that the sample material does not even need to be thawed.

Numerous possible applications

The studies carried out by the researchers on the skin of various test persons lead in quite a different direction. Traces of nicotine, coffee and explosives could all be detected on the skin. According to Zenobi The methods strength is that it is fast and non-invasive, and needs no special sample preparation. In view of the numerous possible applications, it is not surprising that the new method is of interest not only to foodstuffs technologists and safety experts but also to medi-cal professionals and drugs investigators in sport.


'/>"/>

Contact: Professor Renato Zenobi
zenobi@org.chem.ethz.ch
41-446-324-376
Swiss Federal Institute of Technology
Source:Eurekalert

Related biology news :

1. Color-blind method opens new doors in DNA sequencing
2. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
3. Studies reveal methods viruses use to sidestep immune system
4. An entropy-based gene selection method for cancer classification using microarray data
5. New Mixing Method for Microchip-Sized Labs
6. New methods of gene delivery using lasers
7. Breakthrough method in nanoparticle synthesis paves the way for new pharmaceutical and biomedical applications
8. Computational Method Speeds Mapping of Cell Signaling Networks
9. Shift of weather patterns necessitates rethinking of reforestation methods
10. Scientists use manufacturing methods to reconstruct mastodon
11. Researchers develop promising new gene network analysis method
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... -- On Monday, the Department of Homeland Security (DHS) ... for the Biometric Exit Program. The Request for Information ... explains that CBP intends to add biometrics to confirm ... States , in order to deter visa overstays, ... Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/15/2016)... , June 15, 2016 ... market report titled "Gesture Recognition Market by Application Market - Global ... 2016 - 2024". According to the report, the  global ... billion in 2015 and is estimated to grow ... 48.56 billion by 2024.  Increasing application ...
(Date:6/3/2016)... 3, 2016 Das ... Nepal hat ein 44 ... geprägter Kennzeichen, einschließlich Personalisierung, Registrierung und IT-Infrastruktur, ... Produktion und Implementierung von Identitätsmanagementlösungen. Zahlreiche renommierte ... Januar teilgenommen, aber Decatur wurde als konformste ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... June 27, 2016  Global demand for enzymes ... through 2020 to $7.2 billion.  This market includes ... cleaning products, biofuel production, animal feed, and other ... and biocatalysts). Food and beverages will remain the ... increasing consumption of products containing enzymes in developing ...
(Date:6/27/2016)... ... June 27, 2016 , ... Parallel 6 , the leading ... the Clinical Reach Virtual Patient Encounter CONSULT module which enables both audio ... and clinical trial team. , Using the CONSULT module, patients and physicians can schedule ...
(Date:6/27/2016)...   Ginkgo Bioworks , a leading organism ... today awarded as one of the World Economic ... most innovative companies. Ginkgo Bioworks is engineering biology ... world in the nutrition, health and consumer goods ... customers including Fortune 500 companies to design microbes ...
(Date:6/24/2016)... ... ... Researchers at the Universita Politecnica delle Marche in Ancona combed medical journal ... Their findings are the subject of a new article on the Surviving Mesothelioma website. ... the blood, lung fluid or tissue of mesothelioma patients that can help point doctors ...
Breaking Biology Technology: