Utilizing silver and gold nanoparticles for investigation of bacterial cell wall biochemical structure

Due to its "fingerprinting" property, surface-enhanced Raman scattering (SERS) can give significant amount of molecular information about molecular structures in the close vicinity of gold or silver surfaces in a short time. The requirement that the noble metal nanoparticles must be close to the molecular structure for the signal enhancement in SERS can serve as a sensing tool. This study investigates the use of the gold and silver nanoparticles in a controlled manner to obtain molecular level information from microorganisms. The results demonstrate that pH of the sample, the type, surface charge, concentration and arrangement of nanoparticles have a great impact on SERS spectra of bacteria. The finding of these experiments can be used to monitor the changes on the bacterial cell wall and development of novel diagnostic tools for fast microbial identification and discrimination.