Determination of Polyaromatic Hydrocarbons in Particulate Matter with HPLC and 3D-Detector

High Performance Liquid Chromatography (HPLC) with a three dimensional fluorescence detector (3D-detector) was applied for the specification of polyaromatic hydrocarbons (PAHs) in particulate matter (PM) emitted from tailpipe emissions.

Fourteen standard PAHs including Benzo(a)pyrene (B(a)P) and one nitro-PAH (1-Nitropyrene) were examined for the repeatability and limit of detection (LOD) for the HPLC instrument in the test laboratory using the CARB method. The LODs for five PAHs including B(a)P and 1-Nitropyrene were low enough (less than 0.2 ng/ml).

The detailed B(a)P analysis with 3D-chromatograms was carried out to examine the existence of unknown compounds in the peak of B(a)P.

Four excitation wavelengths were selected for the detection of the B(a)P in the real PM samples according to the shape of the spectrum for standard B(a)P and these analytical values were compared each other. Some obvious differences were observed among these four values responding to the change of the spectrum shapes. It is proposed that the lowest value among four datapoints should be used for the analytical result because this value must be less interfered by other unknown compounds.