title: Dispersive solid-phase microextraction method for sample extraction in the analysis of four tetracyclines in water and milk samples by high-performance liquid chromatography with diode-array detection.
abstract: A dispersive solid-phase microextraction (dispersive-SPME) method for the determination of tetracycline, oxytetracycline, chlortetracycline and doxycycline is proposed. Different silica-based and polymeric sorbents were evaluated for their capacity to simultaneously preconcentrate tetracyclines (TCs) in the dispersive format from aqueous or organic solutions. Silica-based sorbents especially functionalized with primary amine, secondary amine, or carbonyl groups have showed higher capacity than polymeric sorbents under organic environment. In the proposed dispersive solid-phase microextraction method, after extraction with acetonitrile and salt-promoted partitioning, TCs were adsorbed to a small amount of dispersive silica-based primary and secondary amine sorbents, desorbed with a small volume of desorption solution, and determined by high-performance liquid chromatography with diode-array detection. Under the optimal conditions, recoveries were determined for surface water and milk samples spiked at 10 ng/mL and 50-150 ng/g, respectively, and quantification was achieved by matrix-matched calibration. The calibration curves of four TCs in both samples showed linearity with a correlation coefficient value above 0.997. Average recoveries ranged from 97.1 to 104.1% and the precision was from 2.0 to 5.6%. Limits of detection ranged from 0.7 to 3.5 ng/mL and from 7.9 to 35.3 ng/g for four TCs surface in surface water and milk samples, respectively.
authors.affiliation: Department of Food Science, National Pingtung University of Science and Technology, Pingtung, Taiwan.
authors.forename: Wen-Hsien
authors.initials: WH
authors.lastname: Tsai
authors.forename: Tzou-Chi
authors.initials: TC
authors.lastname: Huang
authors.forename: Joh-Jong
authors.initials: JJ
authors.lastname: Huang
authors.forename: Yi-Huu
authors.initials: YH
authors.lastname: Hsue
authors.forename: Hung-Yi
authors.initials: HY
authors.lastname: Chuang
mesh_terms: D000327:Adsorption; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry; D052617:Solid Phase Microextraction / Q000379:methods*; D013754:Tetracyclines / Q000032:analysis*; D014867:Water / Q000737:chemistry*
chemical_list: D013754:Tetracyclines; D014867:Water; D012822:Silicon Dioxide