Abstract
A nonderivatization analytical method has been developed to analyze C6−C20 fatty acids and cis-pinonic acid on a GC/FID and a GC/MSD using a polar DB−FFAP capillary column. On the GC/FID, the response was highly linear over concentration ranges >2 orders of magnitude (R2 = 1.00). Using a mixed solvent of dichloromethane (DCM): methanol (3:1, v/v) and an extraction temperature of 40 °C, the method recoveries of the acids from spiked filters were 81−115% based on deuterated surrogates, and the relative standard deviations were 2.5 samples from NIST using this nonderivatization method showed that the efficiency and accuracy were comparable to the derivatization method. Compared with existing derivatization methods, the method is accurate and sensitive, yet simple to use. This method was applied to PM2.5 ambient aerosols collected from a forest site and at a traffic tunnel outlet in the greater Vancouver area in Canada. Total fatty acids (sum of C6−C20) in the aerosols were measured as 20.2−138.7 ng/m3 at the forest site and 100.2−264.6 ng/m3 at the tunnel site. The cis-pinonic acid concentrations were 1.6−44.2 ng/m3 in the forest and from below detection to 6.5 ng/m3 at the tunnel outlet.

This publication has 20 references indexed in Scilit: