| Sample pretreatment is a key procedure in the complex mixtures analysis. As a simple, effective, and low solvent consumption technique, solid-phase extraction (SPE) has been widely used in the pretreatment of complex matrices. In this dissertation, a novel SPE sorbent was synthesized and its adsorption behavior was studied.Reversed-phase interactive hypercrosslinked polymer resin (HXLPP) was synthesized using precipitation polymerization with the monomers of divinylbenzene and p-vinylbenzylchloride, and 2,2-azobisisobutyronitrile as initiator and ferric chloride as catalyst. The HXLPP resin was then chemically modified with 1,2-ethylenediamine group into weak anion-exchange hypercrosslinked polymer resin (HXLPP-WAX-EDA). The surface area and diameters of the prepared HXLPP-WAX-ED A resin were 1340 m2/g and 3-6μm, respectively. As a SPE sorbent, the extraction performance of the HXLPP-WAX-ED A resin was evaluated subsequently by using four acidic compounds of uric acid,p-aminobenzoic acid, hippuric acid and homovanillic acid in urine. The results showed that the recovery was ranging from 98.5%-102.9%. As an application, we used the sythesized SPE sorbent to analyze hippuric acid in human urine samples. The results showed that the HXLPP-WAX-EDA resin not only had a good extraction capability of hippuric acid, but also removed most of interferential urinary uric acid, which could achieve the extraction and purification of human urine.Additionally, a HPLC method was also developed for the determination of uric acid in human urine. Urine samples were successfully separated on an ACE 5 AQ hydrophilic column. The linear curve of uric acid concentration was within the range of 7.1-224.6μg/ml and the average recovery was 99.7%-100.5% with the RSD value below 1.37%. The analytical results of urine samples showed that there was no significant difference in the concentration levels of urinary uric acid between healthy persons and liver cirrhosis patients.
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