Porous Hexagonal Boron Nitride as Solid-Phase Microextraction Coating Material for Extraction and Preconcentration of Polycyclic Aromatic Hydrocarbons from Soil Sample

Sample pretreatment plays important role in the analysis and detection of trace pollutants in complex matrices, such as environmental and biological samples. The adsorption materials of sample pretreatment receive considerable attention, which has a significant effect on the sensitivity and selectivity of the analytical method. In this work, the porous hexagonal boron nitride (h-BN) was utilized as a coating material of solid-phase microextraction (SPME) to extract and preconcentrate polycyclic aromatic hydrocarbons (PAHs) prior to separation and detection with GC-FID. Attributed to the multiple interactions including hydrophobicity, hydrogen bonding and strong π-π interaction, the h-BN coating showed excellent extraction performance for PAHs. Under the optimal conditions, the method showed the linear relationship in the range of 0.1-50 ng mL^-1 for acenaphthene, 0.05-50 ng mL^-1 for pyrene, and 0.02-50 ng mL^-1 for fluorene, phenanthrene and anthracene with a correlation coefficient (R²) not lower than 0.9910. The enrichment factors were achieved between 1526 and 4398 for PAHs with h-BN as SPME fiber coating. The detection limits were obtained in the range of 0.004-0.033 ng mL^-1, which corresponds to 0.08-0.66 ng g^-1 for soil. The method was successfully applied to analysis of real soil samples. The recoveries were determined between 78.0 and 120.0% for two soil samples. The results showed that h-BN material provided a promising alternative in sample pretreatment and analysis.