Cellulose dialysis membrane tubing doped with gold nanoparticles as SERS substrate

In this study, we report for the first time the use of a dialysis method for simple preparation of a flexible substrate for Surface-Enhanced Raman Spectroscopy (SERS). The method consists of synthesized citrate gold nanoparticles capped with poly(allylamine-hydrochloride), poured into a commercial cellulose dialysis membrane, and set into a glass beaker with water under magnetic stirring for 48 h for dialysis. Then gold nanoparticles doped the cellulose membrane to get a SERS substrate, which was characterized by Raman spectroscopy using 4-Aminothiophenol, and 4-Mercaptobenzoic acid as a Raman probe in the range from 1×10−5 to 1×10−10M, Raman signal as a function of logarithm concentration shows a linear behavior and estimated analytical enhancement factor of the substrate using 4-Aminothiophenol was 4.3×105. The flexibility of our SERS substrate can be helpful in applications where solid SERS substrates have low performance. For example, when the surface needs bending for sample preparation or analysis, cut out into small pieces or washed without losing its SERS properties.