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G Petzinger

Publications and source records attributed to G Petzinger.

23 records · Page 2Linked to original sources

Structure and fragmentation mechanisms of some ions in the mass spectrum of ephedrine.

This paper describes the use of gas chromatography mass spectrometry for the confirmation of ephedrine in adulterated powdered ipecac and ipecac fluid extract. Deuteration studies of ephedrine hydrochloride and some related compounds were also performed in an attempt to postulate structures for some of the fragment ions appearing in the spectrum of ephedrine.

Chemical Phenomena↗

Negative ion chemical ionization mass spectrometric method for confirmation of identity of aflatoxin B1: collaborative study.

An interlaboratory study of a negative ion chemical ionization mass spectrometric (MS) confirmation procedure for aflatoxin B1 was conducted in laboratories in the United States, England, and West Germany. Twelve partially purified, dry film extracts from naturally and artificially contaminated roasted peanuts, cottonseed, and ginger root containing varying quantities of aflatoxin B1 were distributed to the participating laboratories. The extracts required additional cleanup before MS analysis, using either an acidic alumina column and preparative thin layer chromatography (TLC) or a 2-dimensional TLC procedure. Recovery of purified aflatoxin B1 was influenced by the degree of recovery of sample from acid alumina and/or the TLC plate and incomplete elution of aflatoxin B1 from silica gel. Factors affecting MS confirmation included the purity and recovery of aflatoxin and MS instrument sensitivity. Aflatoxin B1 identity was confirmed in 19.5, 90.9, and 100% of samples containing less than 5, 5-10, and greater than 10 ng aflatoxin B1/g product, respectively, by solid probe introduction using full mass scans. The MS method has been adopted official first action.

Aflatoxin B1↗

Purge-and-trap gas chromatographic-mass spectrometric determination of benzene in denture adhesives.

A purge-and-trap gas chromatographic-mass spectrometric procedure is presented for determination of trace levels of benzene in denture adhesives and their raw materials. The limit of quantitation is 10 ppb, reproducibility is +/- 10%, and recoveries of d6-benzene are 70-85%. Results of a nationwide survey of 109 finished products and their raw materials representing 32 brand name products from 17 manufacturers are reported.

Adhesives↗

Gas chromatographic/mass spectrometric analyses of unknown analytical response in imported Fava beans: 4-chloro-6-methoxyindole.

A halogenated unidentified analytical response (UAR) was encountered in a number of imported Fava bean samples during the Food and Drug Administration's routine pesticide-monitoring program. Gas chromatographic/mass spectrometric (GC/MS) analyses identified the halogenated component as 4-chloro-6-methoxyindole, a naturally occurring promutagen in Fava beans that has been linked to incidents of gastric cancer. Data from electron impact, positive and negative chemical ionization, collision-induced dissociation, and deuteration studies of this compound are presented, along with GC retention time data.

Fabaceae↗