SERS based detection of glucose with lower concentration than blood glucose level using plasmonic nanoparticle arrays

Surface Enhanced Raman Scattering (SERS) based detection of glucose, without using binder molecule, is difficult due to very small Raman scattering cross section of glucose and its very low affinity/binding with metal nanoparticles. This was overcome by using coupled plasmonic arrays of metal nanoparticles, which produced large field enhancement responsible for higher SERS intensity. It has been observed that the Raman intensity of glucose deposited on patterned Si with silver nanoparticle arrays is higher compared to that on plane Si and plane Si with randomly ordered nanoparticles. The nanoparticle arrays on patterned Si can detect glucose concentration as low as 5 × 10−5 g/ml, which is much lower than blood glucose level. The method can be used for the development of low concentration detection technologies for glucose.