Surface molecular imprinting onto silver microspheres for surface enhanc24 June 2013ed Raman scattering applications

• DOI: 10.1016/j.bios.2013.06.002
• Publication Date: 2013-06-25T14:06:41Z
• Authors: Limin Chang; Yan Ding; Xin Li
• Keywords: Molecular Imprinting; Silver; Limit of Detection; Sulfhydryl Compounds; Spectrum Analysis, Raman; Benzoates; 01 natural sciences; Microspheres; 0104 chemical sciences

A simple route for the synthesis of core-shell Ag-molecularly imprinted polymer (Ag@MIP) hybrid was proposed. Silver microspheres were first fabricated by the acid-directed self-assembly technique, and then they were modified using coupling agent, core-shell Ag@MIP hybrid were finally obtained through surface molecular imprinting technique. The morphology and structure of the resulting hybrid were characterized by X-ray diffraction, energy dispersive spectroscopy, transmission and scanning electron microscopy, and Fourier transform infrared spectroscopy. The obtained Ag@MIP substrate is extremely high surface enhanced Raman scattering (SERS) activity toward the target molecule 4-mercaptobenzoic acid (4-MBA)，and exhibits a 10(-15)M detection limit. The SERS signals of 4-MBA show good reproducibility and selectivity. A possible mechanism for our SERS enhancement was briefly discussed using a molecularly imprinting "gate effect" model. Our experimental results show that the Ag@MIP hybrid as SERS platform is potential for ultrasensitive sensing and analytical applications.