Preparation Of A Hydrophilic Interaction Polymer Monolithic Column And Its Application In Extraction Of Phenols In Environmental Waters

Phenolic compounds are some of the most important contaminants present in theenvironment. Phenols are widely used in the production processes of some products such asplastics, dyes, pesticides, papers, and petrochemicals. As a result, phenols are often found inwaters, soils and sediments. Because most phenols exhibit a high degree of toxicity andadverse effects upon biota and humans, the European Union and the World HealthOrganization (WHO) have listed some of these compounds as priority pollutants anddetermined their maximum permissible levels in surface, ground and drinking waters.However, it is quite difficult for the UV detector to analyze trace amounts of phenols inenvironmental waters. Therefore, it is necessary to establish a technique for pre-concentrationof the trace amounts of phenols.Solid-phase microextraction (SPME) is a relatively new and excellent samplepretreatment technique because of its several attractive advantages such as fastness, lowsample consumption, high selectivity and so on. Polymer monoliths are an importantalternative as absorbents in SPME due to several merits including easy preparation, highsuitability for a wider range of pH values, and good permeability. Therefore, monolithiccolumns have been widely applied in the SPME of analytes from complex matrixes, such asbiological and environmental samples. Hydrophilic interaction chromatography (HILIC) hasbeen widely recognized as a distinct chromatography mode and has enjoyed rapid growth inseparating and extracting very polar compounds.In the present study, a hydrophilic interaction monolith was prepared by in-situpolymerization of glycidyl metharylate(GMA), methacrylic acid,2-(dimethyl amino) ethylmethacrylate and ethylene dimethacrylate in the presence of binary porogens consisting ofdodecanol and cyclohexanol in a150μm i.d. fused silica capillary, and then by opening theepoxy groups on the GMAs to diol groups to further enhance the polarity of the stationaryphase with hydrochloric acid. The optimal conditions for preparing the column wereestablished. After several parameters including the composition of desorption solution,sample volume, sample flow rate and pH value of the sample matrix were optimized, theprepared column was evaluated in terms of enhancement factor and limit of detection (LOD)using phenol in standard sample solutions as the test analyte, and the enhancement factor andLOD were determined to be106and3.9ng/mL, respectively. Finally the method was applied for the determination of trace phenol in a river water sample, and satisfactory recoveries(92.5%－104.2%) and relative standard deviation (RSD=4.6%, n=3) were obtained.