Application of Novel Porous Organic Frameworks in High-Throughput Screening of 21 Glucocorticoids in Surface Water

The polymerization was carried out with 1,2-dichloroethane as solvent, ferric chloride as catalyst, 1,3,5-triphenylbenzene and toluene as monomers and dimethoxymethane as crosslinking agent. When the reaction was completed, the crude product was extracted by Soxhlet with methanol as solvent. The novel porous organic frameworks (POFs) with phenyl functional group were obtained after drying and grinding. The novel POFs solid phase extraction (SPE) column was filled with optimized packing amounts. The aim was to develop a new pretreatment method for the analysis of 21 glucocorticoids in surface water. And the adsorption performance of the novel POFs SPE column was tested by repeatability test. It was shown that the adsorption performance and stability were good with 20 mg of the POFs SPE column. And the POFs SPE column could be reused at least 5 times, which reduced the consumption of disposable experimental supplies. Based on the pretreatment of the surface water with the POFs SPE column, high performance liquid chromatography-quadrupole/field orbitrap high resolution mass spectrometry (HPLC-Q/Orbitrap MS) was used for high-throughput screening of 21 glucocorticoids in surface water. The linear ranges of the standard curves for 21 glucocorticoids were 20-100 μg·L^-1, with the same lower limits of determination of 20 μg·L^-1. This method was applied to the analysis of water samples in actual reservoirs, and glucocorticoids were widely detected in the water samples of the six reservoirs with total detected amounts in the range of 2.68-11.64 μg·L^-1. The results were on the same level of magnitude to those obtained using the Cleanert PEP-2 SPE column, which indicated that two SPE columns had similar effects on the enrichment and concentration of glucocorticoids in water samples.