Migration analysis of DEHP from Inner Liner of Beer Bottle Caps by HPLC

The quality and quantity of DEHP (Di-(2-ethylhexyl) phthalate) migration from inner liner of beer bottle caps were investigated using HPLC (high performance liquid chromatography) with a PDA detector. Methanol/water (95:5 V/V) solution and ethanol were used as extracting solvents, respectively. The HPLC method involved a C18 column at 30oC, a mixture of methanol-water (95:5, v/v) as mobile phase and detection at 275 nm. The results show that the extraction compound from the inner liner of beer bottle caps is DEHP. The detection limit of the method is 3 μg/ml (S/N=3). Precision relative standard deviations (RSD) for 100 μg/ml and 200 μg/ml DEHP standard solution were 1.5% and 0.6% (n=7). In range of 10-200 μg/ml linearity regression equation was Y=1789.41X-1701.80(Y: peak area, X: concentration, μg/ml) with linear correlation coefficient (R2) 0.9982. Recovery rates for DEHP in methanol-water (95:5, v/v) solution ranged from 97.9 to 109.3% and in ethanol from 107.0 to 114.2%, with repeatability RSD smaller than 1.0%.