Abstract: Nowadays novel sensing technologies are needed for biosensing and medicine. There is a considerable effort directed towards the development of novel label-free and sensitive approaches for biosensors. During my work I participated in the research at the Nanotechnology Laboratory of BME-ETT, where the development of a versatile optical sensor, which utilizes localized surface plasmon resonance (LSPR) on gold nanoparticles (Au NPs) is conducted. My goal was to investigate alternative LSPR sensor transducer fabrication technologies which would enable the production of low cost and disposable sensor chips, without losing sensitivity compared to previously existing technologies. For this purpose, gold nanoparticles in various size and distribution were generated by thermally annealing gold thin films (15-50 nm) which were sputtered on glass substrate. The nanoparticles, which were created by varying the technological parameters of the process (sputtered gold layer thickness, thermal annealing temperature and time) were characterized by atomic force microscopy (AFM). A measurement setup consisting of a microfluidic cell and an optical spectrophotometer was constructed to measure the shift of the surface plasmon resonance spectra of the gold nanoparticles in different media. The optimization of the technological parameters – keeping in mind the requirements of the application as a biosensor transducer – was done based on our results.