You could try silica SPE (DOI: 10.1002/jhrc.1240140205), an aminosilane SPE cartridge (ala http://dx.doi.org/10.1016/j.combustflame.2005.09.008) or silver ion silica SPE (DOI: 10.1021/ac9910482) although that was validated on crude, not diesel. 

Separately, must you extract? Why not dilute and analyze as the California Air Resources Board does (DOI: 10.1021/es981227l)? 

You may want to consider if  you only want to measure the 16 priority EPA PAH's, 2ring PAHs, 3ring PAHs, or all PAH containing structures (including aliphatic PAHs).

You can use silica gel chromatography and elution with hexane.

Dear all, 

Thank you so much for your useful guidance.

Sincerely,

Mohammad

Dear Dr. Luke K Ackerman,

I want to analyze the diesel fuel content (16 EPA PAHs according to the Euro 4; 11% V/V) not its emission in air. 

Best, Mohammad