Fluorescence techniques are very useful for understanding the various processes in biological science. This thesis presents the applications of several fluorescence techniques for studying the mobility of proteins and fluorescence dyes inside the living cells and in the silica hydrogel materials. Chapter 1 gives a brief introduction of various fluorescence techniques, including fluorescence polarization and anisotropy, fluorescence recovery after photobleaching, fluorescence modulation, etc. In addition, the basic principle of fluorescence microscopy is covered. Chapter 2 talks about the setup of the home-built fluorescence microscope as well as the polarization alignment that were applied in this thesis. In Chapter 3, the behavior of various entrapped guest molecules within a silica hydrogel was investigated and the effects of Coulombic interactions and physical confinement on molecular mobility were evaluated using fluorescence techniques. In Chapter 4, the motion of E. Coli inner membrane protein TonB was studied using fluorescence anisotropy in order to understand TonB's mechanism in facilitating iron transport in E. Coli. In Chapter 5, the effects of the submicroscopic confinement exerted by the liposomes in the hydrogel on the mobility of entrapped molecules were examined using fluorescence polarization modulation and fluorescence anisotropy.