Navigation Links
Stevens researchers provide new information about mass spectrometry
Date:10/15/2007

HOBOKEN, N.J. Fresh data on mass spectrometry are presented in the report Low-energy collision-induced fragmentation of negative ions derived from ortho-, meta-, and para-hydroxyphenyl carbaldehydes, ketones, and related compounds, produced by Professor Athula Attygalle and his colleagues in the Center for Mass Spectrometry at Stevens Institute of Technology.

According to a study, Collision-induced dissociation (CID) mass spectra of anions derived from several hydroxyphenyl carbaldehydes and ketones were recorded and mechanistically rationalized. For example, the spectrum of m/z 121 ion of deprotonated ortho-hydroxybenzaldehyde shows an intense peak at m/z 93 for a loss of carbon monoxide attributable to an ortho-effect mediated by a charge-directed heterolytic fragmentation mechanism.

In contrast, the m/z 121 ion derived from meta and para isomers undergoes a charge-remote homolytic cleavage to eliminate an *H and form a distonic anion radical, which eventually loses CO to produce a peak at m/z 92. In fact, for the para isomer, this two-step homolytic mechanism is the most dominant fragmentation pathway. The spectrum of the meta isomer on the other hand, shows two predominant peaks at m/z 92 and 93 representing both homolytic and heterolytic fragmentations, respectively. (18)O-isotope-labeling studies confirmed that the oxygen in the CO molecule that is eliminated from the anion of meta-hydroxybenzaldehyde originates from either the aldehydic or the phenolic group. In contrast, anions of ortho-hydroxybenzaldehyde and 2-hydroxy-1-naphthaldehyde, both of which show two consecutive CO eliminations, specifically lose the carbonyl oxygen first, followed by that of the phenolic group. Anions from 2-hydroxyphenyl alkyl ketones lose a ketene by a hydrogen transfer predominantly from the alpha position. Interestingly, a very significant charge-remote 1,4-elimination of a H(2) molecule was observed from the anion derived from 2,4-dihydroxybenzaldehyde, wrote Attygalle and his colleagues from Stevens.

The researchers concluded: For this mechanism to operate, a labile hydrogen atom should be available on the hydroxyl group adjacent to the carbaldehyde functionality.


'/>"/>

Contact: Patrick A. Berzinski
pberzins@stevens.edu
201-216-5687
Stevens Institute of Technology
Source:Eurekalert

Related biology technology :

1. UW-Stevens Point Professor Receives Patent Approval For New Technology
2. Tapping hidden assets: Wisconsin researchers who can create jobs
3. National Academies induct five UW researchers
4. Wisconsin researchers defend stem cell company
5. NimbleGen partners with leading researchers
6. Medical College researchers win federal grants
7. Researchers say scientific reporting needs more perspective, less hype
8. Congress passes bill to ease researchers collaboration worries
9. Researchers report development of embryonic stem cells without destroying embryo
10. New digs for UW AIDS researchers
11. Medical College researchers receive new grants to enhance discovery of heart-protecting anesthetics
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:9/21/2017)... ... (PRWEB) September 21, 2017 , ... ... scientific and technical congress to review the latest knowledge on these products, which ... international speakers will discuss the impact of Biostimulants on Plant Nutrition, Abiotic Stresses, ...
(Date:9/21/2017)... ... September 21, 2017 , ... Today, BioPharma Institute, a leading ... addition of 5 new courses to its prospectus. These include the eagerly-awaited ... Part 11 on Electronic Records and Electronic Signatures (Part 11 of Title 21 ...
(Date:9/21/2017)... ... September 21, 2017 , ... ... the election of Paul Hermes, Entrepreneur in Residence at Medtronic, Inc., to serve ... developed a proprietary, tissue-engineered scaffold for anterior cruciate ligament (ACL) reconstruction that is ...
(Date:9/20/2017)... ... September 20, 2017 , ... Diversity focused business accelerator, The Refinery ... pitch competition to uncover the top technology-driven, women-led startups in Boston, MA, New Haven/Hamden, ... each city’s entrepreneurial events going on that week – in Boston, it will be ...
Breaking Biology Technology:
(Date:5/16/2017)... May 16, 2017   Bridge Patient Portal ... and MD EMR Systems , an electronic ... for GE, have established a partnership to build ... and the GE Centricity™ products, including Centricity Practice ... These new integrations will allow healthcare ...
(Date:4/18/2017)... Inc., a global expert in SoC-based imaging and computing solutions, has ... features the company,s hybrid codec technology. A demonstration utilizing TeraFaces ® ... be showcased during the upcoming Medtec Japan at Tokyo Big Sight ... Las Vegas Convention Center April 24-27. ... Click here for an image of the ...
(Date:4/11/2017)... April 11, 2017 Crossmatch®, a globally-recognized ... solutions, today announced that it has been awarded ... Projects Activity (IARPA) to develop next-generation Presentation Attack ... "Innovation has been a driving force within ... will allow us to innovate and develop new ...
Breaking Biology News(10 mins):