Detection of 6-Thioguanine by surface-enhanced Raman scattering spectroscopy using silver nanoparticles-coated silicon wafer

•The silver nanoparticles-coated silicon wafer (AgNPs@Si) was served as SERS substrate for the detection of 6-Thioguanine (6-TG).•With the 521cm−1 band of silicon as internal standard, band intensity ratio of 6-TG to silicon, that is I1303/I521, can be used for quantification.•Figures of merit were evaluated (linear range, sensitivity, selectivity, recovery).•The detection limit (S/N=3) is 0.065μmolL−1.