Abstract:

The widespread use of pharmaceutical and personal care products (PPCPs), including antipyretic and analgesic drugs, in the last two decades had led to the existence of PPCP residues in the environment, thus raising concerns about their pseudo-persistent nature and potential threat to human health. Generally, most of the detected contaminants are present at low levels (ranging from ng/L to μg/L) in environmental water. Therefore, advanced analytical methodologies are crucial to monitor the occurrence and distribution of antipyretic and analgesic drugs in environmental water. However, trace analysis of environmental pollutants is always challenging because it is necessary to extract analytes present in the sample at ultralow levels from complex environmental matrices. Therefore, an appropriate sample pretreatment is necessary to enrich the target compounds. Conventional solid-phase extraction materials show poor efficiency for the enrichment of antipyretic and analgesic drugs. We herein report a hydrophilic and lipophilic amphiphilic porous polymeric material GCHM (Guochuang hydrophilic material). GCHM was successfully prepared by a stepwise emulsification and micellization process using N-vinyl-2-pyrrolidone (NVP) and divinylbenzene (DVB) as raw materials. An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of four antipyretic and analgesic drugs in water using our solid-phase extraction (SPE) column. The water samples were extracted and purified by the GCHM solid-phase extraction column, and then analyzed by UPLC-MS/MS. Gradient elution was carried out with 0.1% formic acid aqueous solution and acetonitrile as the mobile phase. The target analytes were separated on an ACQUITY UPLC HSS T3 column (100 mm×2.1 mm, 1.8 μm), and multiple reaction monitoring (MRM) was conducted in the positive electrospray ionization mode. The isotope internal standard method was used for quantitative correction. Comparison of the enrichment efficiencies of Oasis HLB, Bond Elut Plexa, and GCHM revealed that GCHM showed the best performance. Different pH values affecting the enrichment efficiency of the GCHM SPE column were optimized, and the matrix effect was evaluated. The results showed that the four target analytes gave the best enrichment effect on the SPE column at pH 7, and the matrix effect for each substance was between 82.8% and 102.2%, indicating obvious matrix removal after the water sample was purified by the GCHM SPE column. Good correlation coefficients (r) greater than 0.995 were observed for all the target compounds in the range of 1-100 μg/L. The method limits of quantitation (S/N=10) ranged from 1 ng/L to 5 ng/L. The corrected recoveries were 85.6% to 106.4%, and the relative standard deviations (RSD) were under 5.6%. The GCHM solid-phase extraction column is inexpensive and efficient, being suitable for the detection of the four antipyretic and analgesic drugs in water. Subsequently, the occurrence of these selected antipyretic and analgesic drugs in water samples from Shanghai, Jiangsu, and Guangdong provinces were studied. The GCHM column has potential advantages over the commercial imported SPE column and is worthy of widespread application. This column can also aid the enrichment and purification of other compounds with similar structures or properties in water.

Key words: solid-phase extraction (SPE), ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), antipyretic and analgesic drugs, water