| Summary: | 碩士 === 國立中央大學 === 化學研究所 === 98 === Currently, pharmaceuticals are supplied and used in abundance, their residues become major targets in environmental. More than 25% of pharma- ceuticals are market as either recemates or the mixture of diastereoisomers. Although non-steroidal anti-inflammatory drugs(NSAIDs) has been studied for over 20 years, the subsequent environmental occurrence, fate, and effects of these residues are not well understood, especially the effects of chiral residues in our environment. Chiral residues should be concerned because of their different biological and/or toxicological effects from one another. Two widely used NSAIDs, Ibuprofen and ketoprofen, were used as the model chiral compounds in our study. A method of chiral liquid chromatography-tandem mass spectro- metry(LC-MS/MS) was developed to determine the ibuprofen and ketoprofen enantiomers in various water samples. A chiral α1-acid glycoprotein (AGP) column was used to separate two enantiomers. The retention and the enantio- selectivity of the analytes can easily be regulated by addition of tertiary amine N, N-dimethyloctylamine (DMOA) to the mobile phase as a charge modifier. Moreover, various ionization techniques including electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric photoionization (APPI) interfaced with chiral liquid chromatographic methods were evaluated with their ionization efficiencies, matrix effects and limitations. Water samples were extracted by HLB-solid-phase extraction. The limit of quantitation (LOQ) was 100 ng/L for ketoprofen enantiomers in 100 mL of water sample. The spiked recoveries of enantiomers ranged 50-100% while RSD was less than 8% (n=3). However, enantiomers were not detected in five selected water samples. Although DMOA can be added to improve the retention and enantioselectivity, of solute, it may bring seriously matrix effect to affect ionization efficience and detection limitation.
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