The spectroscopic technique based on fluorescence has been widely using in chemical and biological research. Recent years have been witnessing intense research activity in the field of tailoring the emission properties of a fluorophore by plasmonic metal nanoaprticles. The spectral properties of fluorophores can dramatically be altered by near-field interactions with the electron clouds present in metals. These interactions modify the emission in ways not seen in classical fluorescence experiments. As compared to the dipole mediated energy transfer between two fluorophores, the metallic nanoparticles can interact over larger distance and can potentially exploited for imaging, energy transfer and sensing applications. In our studies, we probed the influence of metallic nanoparticles distance-dependent energy transfer, tuning of quantum efficiency, optical properties of mesoporous silica nanoparticle-dye mixture etc. [1-7]