Rapid extraction of trace bisphenol A in real water samples using hollow mesoporous silica surface dummy molecularly imprinted polymers†
Hollow mesoporous silica surface dummy molecularly imprinted polymers (HM-DMIPs) were prepared via surface dummy molecular imprinting combined with a hybrid strategy for the highly selective recognition and rapid separation of trace bisphenol A (BPA) from environmental water samples. The obtained materials were well characterized using TEM, SEM, FT-IR, TG and N2 sorption analysis. Moreover, the proper binding and selective recognition ability were also investigated by a batch rebinding assay. As a control, hollow mesoporous silica surface molecularly imprinted polymers (HM-MIPs), silica surface dummy molecularly imprinted polymers (SiO2-DMIPs) and hollow mesoporous silica surface dummy non-imprinted polymers (HM-DNIPs) were also synthesized. Results showed that HM-DMIPs possessed a fast kinetics, high rebinding capacity of 69.6 mg g−1, 3.0, 2.2 and 4.7 times higher than that of SiO2-DMIPs, HM-MIPs and HM-DNIPs, respectively. Moreover, an extremely high selectivity toward BPA over 4,4′-biphenol, diethylstilbestrol and hydroquinone was obtained and the selectivity coefficients were all above 6.96. The HM-DMIPs could be reused for ten runs, indicating their excellent stability and reusability. The results of theoretical analysis indicated a chemical adsorption process. Furthermore, real water samples were successfully analyzed with HM-DMIPs and high recoveries in the range of 98.7–101.7% were obtained. These results demonstrated that HM-DMIPs could serve as an efficient sorbent for rapid separation of trace BPA from environmental water samples.