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Porous polydivinylbenzene microspheres with high specific surface area were prepared by distillation–precipitation polymerization, and were used as the coating material in headspace solid phase microextraction for extracting polycyclic aromatic hydrocarbons. Compared with the other reported sorbents, PDVB exhibits lower cost and higher extraction efficiency, and the enrichment factors can reach 5963–16 720. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The sensitive detection of polychlorinated biphenyls (PCBs) is crucial for protecting the environment and human health. Herein, we constructed a Materials Institute Lavoisier 88B (MIL-88B)-on-University of Oslo 66 (UiO-66) composite (MIL-on-UiO) with a unique nanoflower morphology, in which highly stable UiO-66 is the precursor, with MIL-88B grown on its surface. MIL-on-UiO was used as a fiber coating for headspace solid-phase microextraction to enrich PCBs. Experimental results demonstrated that MIL-on-UiO provided better enrichment performance for PCBs than single components due to multiple interactions, including π–π stacking, halogen bonding, pore-filling, and steric hindrance effects. The method established using the MIL-on-UiO-based SPME fiber coating provided a good linear relationship in the range of 0.001–50 ng·mL−1, with limits of detection ranging from 0.0002 to 0.002 ng·mL−1 and enrichment factors between 3530 and 7420. In addition, the method was used to detect trace PCBs in water and orange juice achieving satisfactory recoveries (81%–111%). • A MOF-on-MOF composite (MIL-on-UiO) with nano-flower morphology was constructed • The MIL-on-UiO was utilized as fiber coating of solid-phase microextraction to PCBs • High enrichment factor (3533–7421) to PCBs were achieved with MIL-on-UiO as coating • A HS-SPME coupling with GC-FID strategy for detecting PCBs has been developed [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like Co 3 O 4 /C 3 N 5 nanocomposite was synthesized by one-pot solvothermal method. • The Co 3 O 4 /C 3 N 5 composite was used as fiber coating of solid-phase microextraction. • The Co 3 O 4 /C 3 N 5 as fiber coating exhibited high thermal stability (more than 400 ℃) • Good adsorption performance and high enrichment factors (3010–6180) were achieved. Sensitive detection of environmental pollutants that are harmful to organisms is of great significance for prevention of related diseases. In this work, a flower-like Co 3 O 4 /C 3 N 5 composite as solid-phase microextraction fiber coating was developed for extraction of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The Co 3 O 4 /C 3 N 5 composite was derived from the multilayer stacked flower shaped Co(OH) 2 /C 3 N 5 that synthesized by one-pot solvothermal method. Compared with pure monomer materials, the unique structure was maintained and the surface adsorption sites were fully exposed, thereby the adsorption performances of Co 3 O 4 /C 3 N 5 were significantly improved. As a result, the enrichment factors were 3010–5012 for PAHs, and 4499–6180 for PCBs. Under the optimized conditions, the developed method showed wide linear range (0.0005–20 ng mL−1) with good linearity (R2 greater than 0.9912), low detection limits (0.00017–0.061 ng mL−1, S/N = 3) and quantification limits (0.0005–0.2 ng mL−1, S/N = 10) for three PAHs and five PCBs. The RSDs (n = 5) of intraday and interday were 2.28–8.35% and 3.49–9.59%, respectively. The reproducibility between fibers (n = 3) was in the range of 7.84–11.96%. The developed method was successfully applied to real water sample with satisfactory recoveries of 81.07–109.1%. As a simple and robust technique, the proposed method will be an alternative way to the analysis of PAHs and PCBs in real samples. [ABSTRACT FROM AUTHOR]