RESUMEN
Thiol-functionalized magnetic carbon nanotubes (TMCNTs) were employed as the sorbent in the magnetic micro-solid phase extraction (M-µ-SPE) of sulfonamide antibiotics (SAs) in water, milks and chicken meat products prior to high performance liquid chromatography-diode array detector (HPLC-DAD) analysis. The synthesized sorbent was characterized by several spectroscopic techniques. Optimum conditions were: 20â¯mg of TMCNTs at pH 4, 2â¯min extraction time, 10% addition of salt and 30â¯mL of sample volume. Under the optimized TMCNTs-M-µ-SPE and HPLC-DAD conditions, the method showed good linearity in the range of 0.1-500⯵gâ¯L-1 (r2â¯≥â¯0.9950), low limits of detection (0.02-1.5⯵gâ¯L-1), good analytes recovery (80.7-116.2%) and acceptable RSDs (0.3-7.7%, nâ¯=â¯15). The method was applied to tap water (1), milks (15) and commercial chicken meat products (35), SAs were detected in five chicken meat samples (3.0-25.7⯵gâ¯L-1). The method is critically compared to those reported in the literature.