Evidence map›Paper›PMID 22847697›Full record

ArticleRapid communications in mass spectrometry : RCM2012

Isomeric differentiation of polycyclic aromatic hydrocarbons using silver nitrate reactive desorption electrospray ionization mass spectrometry.

Mohammad Eftekhari, Ali I Ismail, Richard N Zare

Abstract read
In one paragraph

Article in Rapid communications in mass spectrometry : RCM, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Mohammad EftekhariDepartment of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
Ali I Ismail
Richard N Zare

Funding

Translational Oncology Research Program (Project-005)P30CA124435 · NCI · STANFORD UNIVERSITY · PI Melinda L. Telli · 2007 to 2026
$71.4M
NCI NIH HHS P30 CA124435
6 · The paper itself

Abstract

rationalePolycyclic aromatic hydrocarbons (PAHs) are nonpolar and difficult to detect by desorption electrospray ionization. We present a new detection method based on cationization with silver ions, which has the added advantage of being able to differentiate PAHs with the same mass but different structure.

methods9,10-Diphenylanthracene and triptycene, in addition to four different groups of PAH isomers: (1) anthracene and phenanthrene, (2) pyrene and fluoranthene, (3) benz[a]anthracene, benz[b]anthracene (tetracene), and chrysene (4) benzo[a]pyrene and benzo[k]fluoranthene, were deposited on a paper surface and bombarded with methanol droplets containing silver nitrate. The resulting microdroplets entered a quadruple mass spectrometer for mass analysis.

resultsThe mass spectrum shows [PAH](+), [Ag + OH + PAH](+), and [Ag(PAH)(n)](+) (n = 1, 2) (and [PAH + O(2)](+) in the case of benz[b]anthracene) ions. PAHs having a bay structure, such as phenanthrene, showed a different tendency to interact with silver ions from those PAHs having a linear arrangement of the fused benzene rings, such as anthracene. The ratios of the [PAH](+) peak intensity to that of [Ag-PAH](+), [Ag + OH + PAH](+), [Ag(PAH)(2)](+), and [PAH + O(2)](+) were used to differentiate the PAH isomers sharing the same molecular formula with different structures. For isomeric mixtures the [PAH](+) to [Ag + OH + PAH](+) ratio was found to be the most useful parameter. The uncertainty in the mole fraction of an isomeric mixture was ±0.09, ±0.13, ±0.25, and ±0.1 for phenanthrene-anthracene, fluoranthene-pyrene, benz[a]anthracene-chrysene, and benzo[a]pyrene-benzo[k]fluoranthene, respectively.

conclusionsA simple method has been developed for the detection of PAHs in desorption electrospray ionization mass spectrometry based on Ag(I) cationization. The method showed a capability to differentiate PAHs isomers (having the same molecular mass) in isomeric mixture with an uncertainty in the mole fraction of about ±0.1. At high inlet temperature and voltage, this method showed better sensitivity but less ability to differentiate between isomeric species.

Identifiers

PMID22847697
PMCPMC4145873

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.