Establishment of a method to detect sulfonamide residues in chicken meat and eggs by high-performance liquid chromatography

- A simple and rapid HPLC-DAD method was developed to determine residues of seven sulfonamide in chicken and eggs using.
- Analytes were separated using a C18 column with mixture of 17 mM acetic acid: methanol: acetonitrile mobile phase.
- The method was validated according to commission decision 2002/657/EC and mean recovery of was 86-108% for all analytes.
- Repeatability and within laboratory reproducibility of the developed method was less than 15%.
- The decision limits and detection capability for all the analytes were between 108 -116 ppb and 129-140 ppb respectively.

Sulfonamides are a group of antimicrobials used for treatment and prevention of infectious diseases in humans and animals. In veterinary practice, sulfonamides are extensively used due to its broad spectrum of activity and low cost. A multi-residue analysis of seven sulfonamides (sulfadiazine, sulfathiazole, sulfapyridine, sulfamerazine, sulfamethazine, sulfamethizole, and sulfamethoxypyridazine) in chicken and eggs using HPLC- DAD detection method has been proposed. Chicken and egg samples were homogenized and extracted with distilled water:ethyl acetate (1:3, v/v) liquid-liquid extraction. The extracts were defatted with n-heptane and dried under nitrogen flow at 55 °C. The dry residue was dissolved in 500 μL methanol:acetic acid:water mixture with a ratio of 10:4:36 (v/v/v) and 10 μL of the sample was subjected to HPLC determination under the following conditions: column, Luna 5 μ C18; particle size, 5 μm; mobile phase, 17 mM acetic acid: methanol: acetonitrile (83:10:7, v/v/v); flow rate, 1.0 mL/min; and detection, 270 nm. The specificity was evaluated by analyzing 30 different blank samples of chicken and eggs in order to verify the absence of potential interfering compounds. No interfering peaks were found around the retention time of analytes in the matrices under investigation. The linear correlation coefficients (r2) for 50-250 ppb range were above 0.99 for all sulfonamides tested. The mean recoveries for chicken and eggs spiked at 50, 100, and 150 ppb were in the range of 86-108% for all analytes. Repeatability and within laboratory reproducibility of the developed method was determined at 100 ppb and quantified as the relative standard deviation was lower than 15%. The decision limits were between 108 and 116 ppb for all analytes whilst the detection capability of all analytes ranged from 129 to 140 ppb. An inexpensive and simple liquid-liquid extraction with isocratic elution mode for rapid analysis of residues of seven sulfonamides in chicken and egg samples using HPLC-DAD detection was established in this study.