Silver Anchored α-MnO2 Nanorods Based SERS Substrates for Salivary Thiocyanate Detection and Application in Oral Cancer Diagnosis

Abstract

Salivary sensors are ideal non-invasive diagnostic platforms for cancer detection owing to the existence of many proteins and metabolites that can reflect individual’s health status. Elevated levels of thiocyanate ( ) in smokers’ saliva may be a potential biomarker indicating increased oral cancer risk due to the nitrosation process. Herein, we report a highly sensitive, label-free, ultrasensitive surface-enhanced Raman spectroscopy (SERS) detection of salivary thiocyanate using silver anchored α-MnO 2 nanorods based SERS substrates for the early detection of oral cancer. The structural and morphological characterization of the synthesised Ag/ α-MnO 2 nanorods have been performed using XRD, FTIR, and TEM analysis. The intensity of SERS peak at around 2170 cm −1 , originating from the −C≡N stretching mode, indicated the concentrations of SCN − ions. The SERS spectra of was recorded at concentrations ranging from 1 to 6 mM, which was utilised to differentiate between smokers and non-smokers and hence to predict the risk of oral cancer.