Analysis of urea in human serum using an oblique angle deposited Ag nanorod surface enhanced Raman scattering substrate

We applied surface enhanced Raman spectroscopy (SERS) for the detection of urea in human serum. An oblique angle deposition method was used to prepare SERS-active substrates consisting of Ag nanorods. To maximize the SERS enhancement, the effects of Ag nanorod length on the SERS signal were analyzed. The SERS signals of different concentrations of urea solutions were measured in order to generate a regression model for use in analyzing the amount of urea in body fluid using the SERS substrate. To examine the feasibility of the fabricated SERS substrate, the amount of urea in human serum was measured using the SERS substrate and compared with that determined via conventional blood analysis.