title: Online eluent-switching technique coupled anion-exchange liquid chromatography–ion trap tandem mass spectrometry for analysis of non-steroidal anti-inflammatory drugs in pig serum.
abstract: A novel method for online extraction, pH-gradient separation, and analysis of nine non-steroidal anti-inflammatory drugs (NSAIDs) was developed by coupling online eluent-switching technique to single anion-exchange chromatographic column/ion trap mass spectrometer (MS) and used for monitoring NSAIDs residues in pig serum. A neutral eluent and a pH-gradient eluent were used for extraction and separation of NSAIDs, respectively. Each of nine NSAIDs has an MS precursor ion of either [M−H]− or [M−Na]−. The extracted ion chromatogram for a specific product ion of each NSAID was used for its quantitative analysis. The dynamic linear ranges of calibration curves were all 0–200 ng mL−1 (R2 > 0.9950). The analysis accuracies estimated by spiking standard concentrations at 20, 100, and 200 ng mL−1 were 80.5–99.9%. The corresponding intra-day and inter-day precisions (RSD%) were 2.5–14.5% and 2.9–15.2%, respectively. The limit of detection/limit of quantitation of NSAIDs were 1.3/4.3, 0.5/1.6, 0.2/0.5, 2.5/8.2, 1.5/4.9, 0.6/2.1, 0.6/2.0, 0.5/1.7, and 0.6/2.1 ng mL−1 for carprofen, diclofenac, flunixin, ibuprofen, ketoprofen, meclofenamic acid sodium, mefenamic acid, niflumic acid, and tolfenamic acid, respectively. After 1 h injection of a dose containing 2 mg kg−1 weight pig of flunixin and tolfenamic acid to the pigs, a residue amount of 3480 ± 36 ng mL−1 and 431 ± 13 ng mL−1, respectively, was reached for the incurred pig serum specimens and both residues were reduced to about 20 ng mL−1 at the time of 24 h.
authors.affiliation: Research Center for Analysis and Identification, Center for Biomedical Technology, and Department of Chemistry, Chung Yuan Christian University, 200 Chung Pei Road, Chungli District, Taoyuan City 32023, Taiwan, ROC; Agricultural Technology Research Institute, No. 52, Kedong 2nd Rd., Zhunan Township, Miaoli County 35053, Taiwan, ROC.
authors.forename: Kai Chun
authors.initials: KC
authors.lastname: Chang
authors.affiliation: Agricultural Technology Research Institute, No. 52, Kedong 2nd Rd., Zhunan Township, Miaoli County 35053, Taiwan, ROC.
authors.forename: Jyh Shiun
authors.initials: JS
authors.lastname: Lin
authors.affiliation: Research Center for Analysis and Identification, Center for Biomedical Technology, and Department of Chemistry, Chung Yuan Christian University, 200 Chung Pei Road, Chungli District, Taoyuan City 32023, Taiwan, ROC. Electronic address: chengce@cycu.edu.tw.
authors.forename: Cheanyeh
authors.initials: C
authors.lastname: Cheng
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange / Q000379:methods; D004350:Drug Residues / Q000032:analysis; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods; D044967:Serum; D034421:Sus scrofa; D013552:Swine; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal