title: Comparison of continuous-flow microextraction and static liquid-phase microextraction for the determination of p-toluidine in Chlamydomonas reinhardtii.
abstract: In this study, two microextraction methods, viz. continuous-flow microextraction (CFME) and static liquid-phase microextraction (s-LPME), were optimized and compared for the determination of p-toluidine in water and Chlamydomonas reinhardtii samples. The calibration curve for p-toluidine was linear in the concentration range of 0.01-5 microg/mL, and the squared regression coefficients (r(2)) for the lines were up to 0.999 for both CFME and s-LPME treatments. Detection limits in CFME and s-LPME were 8.2 ng/mL and 4.9 ng/mL, based on a signal-to-noise (S/N) ratio of 3, respectively. The precision was tested, in five replicates, by analysis of a 100-ng/mL standard solution of p-toluidine and the relative standard deviations were 5.43 and 3.08% for CFME and s-LPME, respectively. The concentration factors were 5.5 and 14.4 for CFME and s-LPME, respectively. s-LPME has a higher extraction efficiency, lower detection limit, and higher concentration factor than that of CFME. Additionally, the s-LPME method is precise and reproducible, and requires only a 3.0-microL microdrop of extraction solvent. Therefore, this procedure is more convenient in use, and viable for qualitative and quantitative analysis of p-toluidine in water and biota samples.
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University, Wuhan, China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Liu
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Chen
authors.forename: Shao
authors.initials: S
authors.lastname: Yang
authors.forename: Xuedong
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D002138:Calibration; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D016825:Chlamydomonas reinhardtii / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid / Q000379:methods; D056890:Eukaryota / Q000378:metabolism; D008832:Microchemistry / Q000379:methods*; D015203:Reproducibility of Results; D012492:Salts / Q000494:pharmacology; D012997:Solvents; D013997:Time Factors; D014052:Toluidines / Q000032:analysis*
chemical_list: D012492:Salts; D012997:Solvents; D014052:Toluidines; C029370:4-toluidine