Study On Poly Butyl Methacrylate Monolithic Column Solid-phase Extraction For Four Hydroxyl Polycyclic Aromatic Hydrocarbons In Urine

Objectives In order to overcome the problems of conventional solid phase extraction?SPE?sorbens in packing and resuing,a novel hydrophobic monolithic syringe was developed.The method using the prepared monolith as sorbent,coupled with high performance liquid chromatography fluorescence detector?HPLC-FLD?was developed for the simultaneous determination of 4 hydroxyl polycyclic aromatic hydrocarbons?OH-PAHs?in urine.Methods A poly butyl methacrylate monolith was prepared in syringe?2 mL?and used as the sorbent.The effects of monomer amount and the reaction time on the performance of the extraction were investigated.The prepared columns were characterized by permeability and surface morphology.The monolithic column was used as the SPE sorbent for the simultaneous determination of 4 OH-PAHs in urine.The parameters influenced on SPE such as loading volume,washing solvent,eluting solvent and volume were investigated in detail.Under optimum conditions,the proposed method was evaluated in terms of limits of detection?LODs?,limits of quantification?LOQs?,recovery,precision linearity and repeatability.The feasibility was further performed by a comparison with commercial C₁₈SPE cartridge.The feasibility of the developed method was further demonstrated for the analysis of 4 OH-PAHs in urine samples of coke oven workers.Results The scanning electron microscope image displayed the porous and uniform morphology of the monolith.The SPE process was performed on the synthesized monolithic column using 3 mL 25 mmol L^-1NaH₂PO₄ solution as washing solvent,and 2mL ACN as eluting solvent.Under the optimized conditions,the linearities in range of1.2-200.0 ng/mL?r>0.9991?were obtained,and the LODs and LOQs of the analytes were 0.06-0.09 ng/mL and 0.2-0.3 ng/mL,respectively.The intra-day and inter-day relative standard deviations were 1.4%-5.3%and 2.6%-7.3%,respectively.The recoveries evaluated with the spiked urine samples of coke oven workers?3 ng/mL?ranged from 75.8%to 117.0%.The feasibility of the developed method was further demonstrated for the analysis of the real samples.Moreover,no significant changes were found in extraction performance after more than 10 usages on one monolithic column.The results of monolithic column and commercial C18 SPE cartridge SPE of 4 OH-PAHs in urine of coke oven workers were comparable.Conclusions Compared with the reported results,the results indicated that the reusable monolith enabled effective purification and enrichment of the four OH-PAHs in urine.The method can be applied to the analysis of OH-PAHs in urine due to its simplicity and accuracy.