Supramolecular Solvent Microextraction of Sulfonamides in Tomato Juice Before HPLC-DAD Determination: Method Validation and Greenness Assessment

Abstract A supramolecular solvent-based microextraction procedure was developed for the extraction of four sulfonamide antibiotics (Sulfaguandin, sulfacetamide, sulfadimidin, and sulfadoxin) in tomato juice before detection using high-performance liquid chromatography equipped with a diode array detector (HPLC-DAD). This study used a supramolecular solvent composed of water, tetrahydrofuran, and 1-undecanol as the extraction solvent. The supramolecular solvent was added to the sample solution at the µL level, and the obtained mixture was vortexed. The analytes moved from the sample solution into the extraction solvent in this step. Parameters such as the type and volume of extraction solvent, the effect of sample pH, and sample volume were optimized. The optimal conditions resulted in linearity in the 1–10 µg mL − 1 concentration range, with regression coefficients ranging from 0.9989 to 0.9997. The detection limit ranged from 0.19 to 0.67 µg mL − 1 , and the limit of quantification ranged from 0.57 to 2.03 µg mL − 1 . The Intra-day repeatability expressed as % RSD was 0.32–2.64%. The comparative analysis shows that both the proposed method and previously reported methods achieved scores ranging from acceptable to excellent in green analysis, as assessed by the Eco-Scale Assessment (ESA) tool. The scores obtained using the Sample Preparation Metric of Sustainability (SPMS) ranged from 4.63 to 6.84, with the proposed method achieving an impressive score of 6.84, significantly surpassing the scores of the reported methods. Furthermore, none of the evaluated methods was classified as green according to the Analytical Greenness metric (AGREE) and the Analytical Greenness metric for sample preparation (AGREEprep) assessments. The proposed SUPRAS-LPME method provides a rapid, low-solvent, and comparatively sustainable alternative for sulfonamide analysis in complex food matrices.