HPLC Determination of Bisphenol S in Water with Separation by Solid Phase Extraction in Matrix Dispersion Using Magnetic Bamboo Charcoal as Adsorbent

The water sample (100.0 mL) was adjusted to pH 4 with dilute nitric acid. 2.5 g of NaCl and 30 mg of self-prepared magnetic bamboo charcoal (MBC) were added into the sample solution. The above mixture was swirled for 8 min to have bisphenol S adsorbed on MBC. The aqueous phase was discarded. Methanol (0.5 mL) was added to the solid phase and the mixture was swirled for 2 min to desorb bisphenol S from MBC into methanol. The methanol solution was separated by HPLC using Spherigel C₁₈ chromatographic column as stationary phase, and a mixture of acetonitrile and H₂O (55+45) as mobile phase. UV-detection was adopted. Linear relationship between values of peak area and mass concentration of bisphenol S was found in the range of 0.1-20 μg·L^-1, with detection limit (3S/N) of 0.05 μg·L^-1. 1.0 μg·L^-1 standard solution of bisphenol S was determined by the above method for 7 times, giving value of RSD of 5.6%. Two determination were made in testing for recovery by standard addition method, values of recovery found were 88.7% and 90.6%.