State Key Laboratory of Bioreactor Engineering & Department of Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
Anal Chim Acta. 2013 May 13;777:57-62. doi: 10.1016/j.aca.2013.03.037. Epub 2013 Apr 1.
Surface-imprinted core-shell Au nanoparticles (AuNPs) were explored for the highly selective detection of bisphenol A (BPA) by surface-enhanced Raman scattering (SERS). A triethoxysilane-template complex (BPA-Si) was synthesized and then utilized to fabricate a molecularly imprinted polymer (MIP) layer on the AuNPs via a sol-gel process. The imprinted BPA molecules were removed by a simple thermal treatment to generated the imprint-removed material, MIP-ir-AuNPs, with the desired recognition sites that could selectively rebind the BPA molecules. The morphological and polymeric characteristics of MIP-ir-AuNPs were investigated by transmission electron microscopy and Fourier-transform infrared spectroscopy. The results demonstrated that the MIP-ir-AuNPs were fabricated with a 2 nm MIP shell layer within which abundant amine groups were generated. The rebinding kinetics study showed that the MIP-ir-AuNPs could reach the equilibrium adsorption for BPA within 10 min owning to the advantage of ultrathin core-shell nanostructure. Moreover, a linear relationship between SERS intensity and the concentration of BPA on the MIP-ir-AuNPs was observed in the range of 0.5-22.8 mg L(-1), with a detection limit of 0.12 mg L(-1) (blank±3×s.d.). When applied to SERS detection, the developed surface-imprinted core-shell MIP-ir-AuNPs could recognize BPA and prevent interference from the structural analogues such as hexafluorobisphenol A (BPAF) and diethylstilbestrol (DES). These results revealed that the proposed method displayed significant potential utility in rapid and selective detection of BPA in real samples.
表面印迹核壳 Au 纳米粒子（AuNPs）被用于通过表面增强拉曼散射（SERS）对双酚 A（BPA）进行高选择性检测。合成了三乙氧基硅烷模板复合物（BPA-Si），然后通过溶胶-凝胶法在 AuNPs 上制备了分子印迹聚合物（MIP）层。通过简单的热处理去除印迹的 BPA 分子，生成具有所需识别位点的印迹去除材料，MIP-ir-AuNPs，这些识别位点可以选择性地重新结合 BPA 分子。通过透射电子显微镜和傅里叶变换红外光谱研究了 MIP-ir-AuNPs 的形态和聚合特性。结果表明，MIP-ir-AuNPs 的制备采用了 2nm 的 MIP 壳层，其中生成了丰富的胺基。结合动力学研究表明，由于超薄膜核壳纳米结构的优势，MIP-ir-AuNPs 可以在 10 分钟内达到对 BPA 的平衡吸附。此外，在 MIP-ir-AuNPs 上，BPA 的浓度与 SERS 强度之间存在线性关系，范围为 0.5-22.8mg L(-1)，检测限为 0.12mg L(-1)（空白±3×s.d.）。当应用于 SERS 检测时，所开发的表面印迹核壳 MIP-ir-AuNPs 能够识别 BPA，并防止结构类似物如六氟双酚 A（BPAF）和己烯雌酚（DES）的干扰。这些结果表明，所提出的方法在快速和选择性检测实际样品中的 BPA 方面具有显著的潜在应用价值。
