1. Sulfadiazine, 0.1 μg mL-1; 2. sulfamerazine, 0.05 μg mL-1; 3. sulfametoxydiazine, 0.1 μg mL-1; 4. sarafloxacin, 0.07 μg mL-1
Figure 4: Chromatograms of the analyte standard solutions.