Chemometric design-based optimization of a green, selective and inexpensive switchable hydrophilicity solvent-based liquid phase microextraction procedure for pre-concentration and extraction of sulfadiazine in milk, honey and water samples.

In this research, a green, selective and inexpensive switchable hydrophilicity solvent-based liquid phase microextraction (SHS-LPME) procedure has been optimized for the extraction and preconcentration of sulfadiazine (SDZ) in milk, honey and water samples prior to spectrophotometric analysis. Five variables affecting the SHS-LPME procedure were optimized using chemometric-based central composite design. For the SHS-LPME procedure, analytical parameters such as linearity, limit of detection, extraction recovery and enrichment factor were 15-300 μg L, 4.5 μg L, 96 ± 3% and 113, respectively. The precision of the method was investigated by repeatability and reproducibility studies. The relative standard deviation from these studies was found in the range of 2.4-4.5%. The recovery of the SDZ in the samples was in the range of 94 ± 4-99 ± 2%. Collected samples were analyzed by both the SHS-LPME procedure and the reference method using flow injection-flame atomic absorption technique, and the results were compared. There was no statistically significant difference between the two methods. This showed that the SHS-LPME procedure can be safely applied to the analysis of real samples.