HPLC Determination of Bisphenol A in Beverages with Its Separation and Enrichment by Solid Phase Extraction Using Room Temperature-Ionic Liquid Loaded Magnetic Nano-composite of Cyclodextrin Polymer/Fe₃O₄

At first, through reaction of hydroxypropyl-β-cyclodextrin with oxacyclochloropropane in alkaline medium hydroxypropyl-β-cyclodextrin polymer was prepared. The polymer obtained was then reacted with sodium chloroacetate to give polymer of carboxymethyl-hydroxypropyl-β-cyclodextrin, which was dissolved together with ferrous sulfate and ferric chloride in water and reacted in ammoniacal solution at 90℃ to give magnetic nanocomposite of hydroxypropyl-β-cyclodextrin polymer/Fe₃O₄. And finally, the nanocomposite was soaked and stirred inC₄minPF₆, and after filtration by suction and the solid substance was dried at 90℃, and the room temperature-ionic liquid loaded magnetic nanocomposite of cyclodextrin polymer and Fe₃O₄ (abbreviated as mangetic nanocomposite, MNC, here after) was obtained. The MNC obtained was used as adsorbent to separate and enrich bisphenol A from samples of beverage by the following optimized procedure:50.0 mL of the sample were taken and after adjusting its acidity to pH 7.0, 0.1 g of the MNC was added and swirled for 5.0 min to have the bisphenol A adsorbed on MNC. The aqueous solution was separated and discarded. 2.0 mL of methanol were added to elute bisphenol A from MNC ultrasonically for 10.0 min. The methanol solution was collected and filtered through 0.22 μm membrane. The filtrate was used for HPLC analysis. Agilent EC-C₁₈ chromatographic column was used as stationary phase and mixtures of acetonitrile (A) and water (B), mixed in various ratios were used as mobile phase in the gradient elution. Fluorescence detector was used for detection. Linearity range for bisphenol A was found between 2.40-800 μg·L^-1, with detection limit (3S/N) of 0.40 μg·L^-1. Enrichment factor found was 25. Test for recovery was made by standard addition method using blank sample of fruit juice as matrix, giving results in the range of 95.0% to 98.0%, and RSDs (n=5) found in the range of 2.3% to 5.1%.