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:10/11/2017)... ... October 11, 2017 , ... ... has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal Transducer and ... of osteosarcoma. SBT-100 is able to cross the cell membrane and bind intracellular ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder ... local San Diego Rotary Club. The event entitled “Stem Cells and ... had 300+ attendees. Dr. Harman, DVM, MPVM was joined by two human doctors: ...
(Date:10/10/2017)... ... October 10, 2017 , ... ... 13 prestigious awards honoring scientists who have made outstanding contributions ... scheduled symposium during Pittcon 2018, the world’s leading conference and exposition for laboratory ...
(Date:10/9/2017)... Arizona (PRWEB) , ... October 09, 2017 , ... ... Kindred, a four-tiered line of medical marijuana products targeting the needs of consumers ... and packaging of Kindred takes place in Phoenix, Arizona. , As operators of ...
Breaking Biology Technology:
(Date:4/5/2017)... 2017 Today HYPR Corp. , leading ... component of the HYPR platform is officially FIDO® ... security architecture that empowers biometric authentication across Fortune 500 ... secured over 15 million users across the financial services ... home product suites and physical access represent a growing ...
(Date:3/30/2017)... ANGELES , March 30, 2017  On April ... Hack the Genome hackathon at Microsoft,s ... exciting two-day competition will focus on developing health and ... Hack the Genome is the ... been tremendous. The world,s largest companies in the genomics, ...
(Date:3/28/2017)... 28, 2017 The report "Video ... Monitors, Servers, Storage Devices), Software (Video Analytics, VMS), and ... Global Forecast to 2022", published by MarketsandMarkets, the market ... is projected to reach USD 75.64 Billion by 2022, ... The base year considered for the study is 2016 ...
Breaking Biology News(10 mins):