Fractionation of diesel particle extracts by sephadex LH-20 and thin-layer chromatography.
A method was developed to concentrate fractions high in bacterial mutagenicity from diesel exhaust particle (DEP) extracts. The two-step fractionation of organic extracts of DEP employed Sephadex LH-20 followed by thin-layer chromatography (TLC). In both steps, nitro-substituted polycyclic aromatic hydrocarbons (nitro-PAHs) were found to co-elute with the fractions of highest specific bacterial mutagenic activity. Although recoveries of mass and mutagenicity from the LH-20 fractionation were high, very low (20-30%) recovery of mutagenicity was found after TLC. Recovery studies using 14C-labeled 1-nitropyrene showed that 78% of the compound was recovered unaltered through the combined fractionation. The most bioactive TLC subfraction was chromatographed using gas chromatography with thermionic specific detection. A sizeable peak was found to co-elute with a nitropyrene standard, but no peak was found co-eluting with nitrofluoranthene. Triple quadrapole mass spectrometry was used to measure the concentrations of nitropyrene in each of the fractions. Nitropyrene was enriched 160-fold in the most bioactive TLC subfraction over the starting material, for a final concentration of over 3200 micrograms g-1. Masses corresponding to several two- and three-ring methylated nitro-PAHs were found in the same fraction, including nitro-(methylbiphenyls/methylacenapthenes) and nitro-(methylanthracenes/methylphenanthrenes).
W E
WE
Bechtold
J S
JS
Dutcher
A L
AL
Brooks
T R
TR
Henderson
D000818:Animals; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D005648:Fuel Oils / Q000032:analysis* / Q000633:toxicity; D013058:Mass Spectrometry; D009152:Mutagenicity Tests; D009153:Mutagens; D010578:Petroleum / Q000032:analysis*; D011083:Polycyclic Compounds / Q000032:analysis; D051381:Rats; D012486:Salmonella typhimurium / Q000235:genetics; D001335:Vehicle Emissions / Q000032:analysis* / Q000633:toxicity
D005648:Fuel Oils; D009153:Mutagens; D010578:Petroleum; D011083:Polycyclic Compounds; D001335:Vehicle Emissions