Surface enhanced Raman spectroscopy hyphenated with surface microextraction for in-situ detection of polycyclic aromatic hydrocarbons on food contact materials.

Highly bioaccumulated polycyclic aromatic hydrocarbons (PAHs) have cause health concerns because of their carcinogenic properties. PAHs could migrate to food from contaminated food contact materials. In this study, a hyphenated technique combining surface enhanced Raman spectroscopy (SERS) with surface microextraction was developed for in-situ on site screening of PAHs on food contact materials. Methanol and 1-propanethiol-modified silver nanoparticles (PTH-Ag NPs) were used to perform the in-situ microextraction and detection of PAHs, respectively. The SERS spectra can be obtained by a portable Raman spectrometer. The vibration of the C-C bond of PTH at 1030cm(-1) was chosen as an internal standard peak. The PTH-Ag NPs showed high uniformity with an RSD of 2.96%. A plot of the normalized SERS intensity against fluoranthene concentration showed a linear relationship (R(2)=0.98). The detection limit could reach 0.27ngcm(-2). The in-situ microextraction-SERS hyphenated technique for the detection of three PAHs at five food contact materials was demonstrated. The method can be also applied to detect PAH mixtures. This in-situ microextraction-SERS hyphenated method demonstrated its ability to rapidly screen PAHs on contaminated food contact materials free from complex sample pretreatment.