Molecularly imprinted microspheres for bisphenol a prepared using a microfluidic device.
ABSTRACT Spherical molecularly imprinted polymer particles for bisphenol A (BPA-MIP) were easily prepared by using a Y-junction microfluidic device. The sizes of the obtained BPA-MIP particles were found to be 86 µm with a narrow size distribution. The binding characteristics were investigated by drawing a binding isotherm to estimate the binding constant and by switching the polarity of solvents to examine the feasibility of use as a medium for affinity chromatography. When dichloromethane was used as a solvent, BPA was strongly bound to the spherical BPA-MIP particles based on hydrogen bond formation; after switching the solvent to methanol, BPA was eluted quantitatively due to the weakening of the hydrogen bonding, suggesting that the spherical BPA-MIP particles can be applied to affinity-type solid-phase extraction for BPA. As the present method can provide a diverse range of spherical MIPs without tedious procedures, MIP-based affinity media will be able to be more readily used as pretreatment and/or purification for various fields.
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ABSTRACT: A simple and fast method for both dummy template selection and polymer composition optimization is proposed here. A series of dummy templates for bisphenols imprinting were screened by running them on a non-imprinted polymer (NIP) column with porogen solvent as mobile phase. The tested dummy templates mainly involved bisphenol S (BPS), bromobisphenol A (TBBPA), bisphenol F (BPF), bisphenol E (BPE), bisphenol B (BPB), bisphenol AF (BPAF), 2,2',6,6'-tetramethyl-4,4'-sulfonyldiphenol (BS-TM) and 4,4'-diaminodiphenylmethane (DADPM). Different monomers and porogens were also investigated for BPS and DADPM using the same method. BPS dummy template was finally selected with acetonitrile and 4-VP as porogen and monomer. The resulting dummy molecularly imprinted polymer (DMIP) achieved superior affinities for BPF, BPE, BPA, BPB and BPAF with imprinting factors 14.5, 13.8, 8.7, 5.7 and 4.2, respectively. An efficient method based on BPS-DMIP-SPE coupled with HPLC-UV was developed for selective extraction of BPF, BPE, BPA, BPB and BPAF in water samples. The method showed excellent recoveries (89.4-102.0%) and precision (RSD 0.3-4.8%, n=5) for tap and river water samples spiked at three concentration levels each (40, 200 and 1000ngL(-1)). The detection limits ranged between 2.2 and 3.8ngL(-1) with a sample volume of 500mL. The result demonstrated the superiority of the optimized method for selective extraction of BPs in water samples at the ngL(-1) level.Journal of Chromatography A 03/2014; · 4.61 Impact Factor