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

J Chromatogr A. 2009 Mar 20;1216(12):2263-9. doi: 10.1016/j.chroma.2009.01.034. Epub 2009 Jan 17.

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.

MeSH terms

  • Adsorption
  • Animals
  • Chromatography, High Pressure Liquid / methods*
  • Hydrogen-Ion Concentration
  • Milk / chemistry*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Silicon Dioxide / chemistry
  • Solid Phase Microextraction / methods*
  • Tetracyclines / analysis*
  • Water / chemistry*

Substances

  • Tetracyclines
  • Water
  • Silicon Dioxide