抄録
Large-volume sample injection technique was utilized for gas chromatography-mass spectrometric determination of ergosterol to estimate fungal biomass of indoor and outdoor air. Sample was collected with a low volume air sampler onto a filer paper for 24 hours and saponified in methanolic KOH. Ergosterol was extracted with n-hexane and then derivatized to its TMS ether. The ergosterol-TMS ether was stable for a month in a refrigerator.
The measurements of ergosterol in the samples were carried out by sample injection of 50 μl using a large volume injector into GC/MS followed by SIM analysis using ions m/z 363, 337 and 468. The lowest detectable amounts of the TMS derivative of ergosterol was 5 pg (signal-to-noise ratio of 3, m/z 363).
Actual air samples had been collected monthly in Nara city from January to December throughout 2006. The samples of indoor and outdoor air contained ergosterol from 0.03 to 0.96 ng/m3 and from 0.04 to 0.49 ng/m3, respectively.