SERS study of bacteria using biosynthesized silver nanoparticles as the SERS substrate

Surface-enhanced Raman scattering (SERS) spectroscopy has great advantages as a spectroscopic analytical tool due to the large enhancement of the weak Raman signal and thereby facilitates suitable identification of chemical and biological systems. SERS can be utilized as a powerful tool to identify pathogens like bacteria. However, it is difficult to fabricate a homogeneous SERS active substrate in biosensing applications to obtain a uniform, stable and highly reproducible SERS signal. In this paper, we have used biosynthesized silver nanoparticles as the SERS active substrate to identify bacteria with different cell wall compositions. The silver nanoparticles were synthesized using the leaf extract of Neolamarckia cadamba as the source of reducing and stabilizing agents. The pathogen detection by using the SERS technique using biosynthesized silver nanoparticles represents a novel approach for rapid microbial diagnostics, where SERS can be directly applied to clinical samples rather than pure cultured bacteria.