Preparation of poly(1,8-diaminonaphthalene)-based molecularly imprinted polymers for rhodamine onto ITO/Au electrodes and analytical application by surface-enhanced Raman spectroscopy (SERS)

Abstract

In this report, poly(1,8-diaminonaphthalene) as a molecularly imprinted polymer (MIP) coated on gold nanoparticles (nano Au) dispersed on ITO electrode was prepared. While nano Au strongly enhance the Raman signal of the analyte, MIP layer allows to selective trap and enrich the analyte molecules close to the Au surface. In fact, by building a polymer matrix around target molecules, in this case is rhodamine B and then extraction of the imprinted molecules, we can create the specific cavities in the MIP shell with a 3D structure complementary to the template molecule in shape and chemical functionality. The rhodamine molecules on ITO/Au/MIP substrate were detected using surface-enhanced Raman spectroscopy (SERS) with an enhancement factor of 10⁶. The SERS peak intensity at 611 and 771 cm^-1 was found to be proportional to the Rhodamine concentration with correlation coefficients of 0.993 and 0.935, respectively. These results open up prospects for development of poly(1,8-diaminonaphthalene) as a molecularly imprinted polymer for applications in plasmonic sensing.