Designing of the functional paper-based surface-enhanced Raman spectroscopy substrates for colorants detection

Abstract Many limitations hinder the practical applications of surface-enhanced Raman spectroscopy (SERS) substrates on the detection of real-world samples, such as collection efficiency for solid samples, separation and preconcentration for liquid ingredient. In this study, polyelectrolytes poly(allylamine hydrochloride) (PAH) and poly(sodium 4-styrenesulfonate) (PSS) were decorated on the surface of AgNP-based filter paper via a simple process. PSS-functionalized paper SERS substrates were utilized for rapid separation, preconcentration and detection of colorants in drinks with complex components. Compared with conventional rigid SERS substrates, separation, preconcentration of analytes can be realized by a surface chemical gradient and electrostatic interaction created by polyelectrolyte coating-paper. Synthetic dyes, such as sunset yellow and lemon yellow were separated and detected successfully in drinks by PSS-functionalized paper SERS substrates. Owing to the low cost, simple preparation process and high separation and preconcentration for the samples, PSS-functionalized paper substrates are promising to be used in solving critical problems for separation and detection of real-world samples.