▎ 摘　　要

A graphene monolithic column was fabricated in a capillary using -electron-rich poly(N-vinylcarbazole-divinylbenzene) as the supporter through in situ one-step polymerization for the enrichment of trace benzodiazepines in biological samples. This new three-dimensional monolith showed uniformity and a continuous column bed; more importantly, it retained the unique properties of graphene that are typically associated with individual graphene sheets. Based on the large delocalized -electron system, graphene forms - stacking interactions with benzodiazepines and benzene rings of poly(N-vinylcarbazole-divinylbenzene), which not only enhance the extraction performance for benzodiazepines compared to the neat polymer but also provide chemical stability of the graphene monolith. Moreover, several factors likely to affect the extraction, including ionic strength, sample pH, sample volume, and eluant volume were studied in detail. The optimized method gave a linear range of 0.005-1ngmL(-1), and detection limits of 1.12-2.35ngL(-1). Finally, the graphene monolith was successfully applied to the separation and enrichment of benzodiazepines from urine and hair samples coupled with high-performance liquid chromatography-mass spectrometry. The recoveries were in the range of 78.6-85.6% for urine and 87.2-94.3% for hair with relative standard deviations of 3.4-6.9 and 2.9-8.3%, respectively.