Aspirin in Food Samples for Separation and Micro Determination of Copper(II) Using Cloud Point Extraction/Solvation Method

In this work, sensitive method was used for the first time by joining cloud point extraction with solvation system (CPE-SS) using aspirin as the organic reagent to form cloud point layer (CPL). It had a wavelength for final absorbance under λ_max = 293 nm. Different kinds and concentrations of salting out with different extraction efficiencies were used to enhance the extraction efficiency. KNO₃ as a salting out under 0.1 M showed maximum extraction efficiency in the presence of 40 µg of Cu(II). The applications of extraction in this method had required the existence of 0.4 mL of Triton X-100 and heating under 85 °C for 20 minutes to form CPL quantitatively. The effect of different surfactants and various organic reagents to investigate the impact of interferences as well as spectrophotometric determination were also investigated in this study. Chicken, breast, cow meat (beef), cucumber, drainage fish, garden cress and lettuce showed low limit of detection (LOD) 0.018 ppm, limit of quantity (LOQ) 0.060 ppm and RSD% of 0.028 in 2 ppm.