Preparation of Graphene Oxide Grafted Silica Monolith and Application in Determination of Polycyclic Aromatic Hydrocarbons

Being priority control environmental pollutants , the determination of polycyclic aromatic hydrocarbons ( PAHs) is of great significance. In this work , a novel silica monolith was prepared by grafting graphene oxide ( GO) onto the surface of silica monolith through amidation reaction. The morphology and structure of the monolith were characterized by scanning electron microscopy, elemental analysis and Raman spectroscopy. Using this monolith as a solid phase microextraction ( SPME ) medium, the extraction performances for typical PAHs were extensively investigated. The enrichment factors of the monolith for Pyrene ( Pyr) , Benzo [ a] pyrene ( BaP ) and dibenzo [ a, h anthracene ( DahA ) were 78. 5 , 98. 2 and 102. 4 , respectively. The excellent enrichment property of the monolith 14 PAHs was attributed to the pi-pi stacking and hydrophobic interactions between GO and PAHs. Therefore, a facile and sensitive detection method for PAHs was developed coupled with high performance liquid chromatography-ultraviolet ( HPLC-UV ) . The linear range was 0. 1-150 mu g/L for nine PAHs (R-2 >= 0. 9947) , with limits of detection ( LOD) and limits of quantification ( LOQ ) of 0. 02-0. 11 mu g/L ( S/N = 3) and 0. 07 -0.36 mu g/L ( S/N= 10) , respectively. The spiked recoveries of PAHs in cigarette smoke, coke waste water and local atmospheric particles were between 81.5% and 107. 8% , with the relative standard deviations ( RSDs ) from 1. 0% to 6. 5% ( n=3 ) . Furthermore , the developed method was accurate , sensitive , simple and reliable , and had great potential applicability in determination of real samples.