A Rapid and Simple Method for Multi-Residue Sulfonamide Analysis in Poultry Meat

Abstract

Background: Sulfonamides are widely used in poultry production for disease prevention and treatment, but their misuse or inadequate withdrawal before slaughter may result in residues in edible tissues. Monitoring these residues requires analytical methods that are sensitive, reliable, and practical for routine use, particularly in laboratories with limited access to advanced mass spectrometry-based instrumentation. Objective: To develop and validate a simple and rapid HPLC-DAD method for the simultaneous determination of five sulfonamide residues in poultry meat, and to assess its applicability to real retail samples. Methods: Five sulfonamides—sulfadiazine, sulfamerazine, sulfadimidine, sulfamethoxazole, and sulfamethizole were extracted from poultry meat using liquid-liquid extraction with ethyl acetate, followed by defatting with n-hexane. Chromatographic separation was performed on a C18 column using isocratic elution with acetonitrile and 0.1% formic acid in water (30:70, v/v), with detection at 270 nm. The method was validated according to ICH Q2(R1) guidelines for specificity, linearity, accuracy, precision, robustness, limit of detection, and limit of quantification. The validated method was then applied to ten poultry meat samples collected from retail markets in Hyderabad, Pakistan. Results: The method showed good linearity over the concentration range of 5-500 ng/mL, with correlation coefficients of 0.99. The limits of detection ranged from 1.2 to 2.8 µg/kg, while the limits of quantification ranged from 3.6 to 8.4 µg/kg, all below the regulatory limit of 100 µg/kg. Mean recoveries ranged from 88.4% to 102.1%, and intra-day and inter-day precision values were below 6% RSD. All five analytes were separated within 8 min, with a total run time of 12 min. Application of the method to retail poultry meat samples showed detectable sulfonamide residues in 38% of samples, with concentrations ranging from 3.4 to 60 µg/kg; none exceeded the regulatory limit. Conclusion: The proposed HPLC-DAD method is simple, rapid, and reliable for the simultaneous determination of five sulfonamide residues in poultry meat. Its satisfactory validation performance, short analysis time, and use of commonly available laboratory equipment make it suitable for routine food safety monitoring, particularly in resource-limited settings.