Vol. 7, Issue 2, Part A (2025)

Polyvinyl pyrrolidone (PVP) capped gold nanoparticles have been prepared in non-aqueous medium, a stronger reducing agent and sodium hydroxide used to maintain the pH of the solution and acts also as reducing agent. The PVP capped gold nanoparticles solutions are wine red and are stable over a long period of time with no induction of aggregation. The particles have been characterized using AFM, TEM, TGA-DSC, UV-Visible spectrophotometer and Fluorescence spectrometer. The solution shows strong visible light absorption; 20 days old solution well defined the particles of about 21 nm diameter in solution. The emission peaks of Fluorescence are observed at 361, 382 and 383 nm at the excitation of 300, 325 and 350 nm respectively. 2 layers coated by LB method shows unique optical properties. Use of plasmonic gold nanoparticles for Cancer diagnosis and photo thermal therapy and leads to strong electromagnetic fields.