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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-6-3
pubmed:abstractText
The determination of 2,3-, 3,4-, 2,6-, 2,4- and 2,5-toluenediamine (TDA) in hydrolysed human urine and blood plasma was studied by GC-MS. The TDA isomers as their perfluoro-fatty acid anhydride derivatives were investigated. Chemical ionization with ammonia and isobutane as reagent gas and monitoring both positive and negative ions are studied. Negative ion monitoring using ammonia and the TDA pentafluoropropionic anhydride (PFPA) derivatives were chosen owing to the low detection limits and good separations of the isomers studied. The ions monitored were m/z 394 and 374 corresponding to the (M-20)- and (M-40)- ions and the m/z = 397 and 377 ions of the tri-deuterium-labelled TDA used as an internal standard. The performance of 2,4-, 2,5- and 2,6-TDA-PFPA in the ion source was studied by varying the ammonia pressure, temperature and electron energy. A 1-ml volume of human urine was added to 1.5 ml of 6 M HCl containing 0.5 micrograms/l of each of the trideuterated 2,6- and 2,4-TDA and the solution was hydrolysed at 100 degrees C overnight. TDA was extracted into 2 ml of toluene by the addition of 5 ml of saturated NaOH solution. Derivatization was performed in toluene by the addition of 10 microliters of PFPA. The excesses of the reagent and acid formed were removed by extraction with 1 M phosphate buffer solution (pH 7.5). Analyses of 2,6-, 2,4- and 2,5-TDA-spiked human urine (0.2-2.5 micrograms/l) were performed. The correlation coefficients were 0.999 (n = 6). The precision (R.S.D.) for human urine spiked at 1 micrograms/l was 1.6% for 2.6-TDA, 3,5% for 2,4-TDA and 3.2% for 2,5-TDA (n = 10). The detection limit, defined as twice the signal-to-noise ratio, was 1-5 fg injected, corresponding to less than 0.05 micrograms/l of TDA in human urine or plasma.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
663
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
199-210
pubmed:dateRevised
2009-1-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Determination of toluenediamine isomers by capillary gas chromatography and chemical ionization mass spectrometry with special reference to the biological monitoring of 2,4- and 2,6-toluene diisocyanate.
pubmed:affiliation
Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't