Immobilization of GFP within Mesoscopically Ordered Thin Film

In general, enzymes demonstrate high selectivity and reactivity under normal biological conditions, but are sensitive to denaturation and inactivation by temperature and pH extremes. Difficulty arises in maintaining stereochemical structure and activity under conditions of interest for practical applications. In particular, Green Fluorescing Protein (GFP), found in certain jellyfish, is optically active when in its native conformation. GFP is known to retain it fluorescence in a wide range of pH and temperature as compared to other proteins, but has a tendency to aggregate in solution and lose fluorescence. Immobilizing GFP, a small but stable protein, within a thin film provides information regarding protein conformation and the extent of aggregation. GFP behavior in the film provides a reference for immobilization of enzymes of comparable dimensions. Immobilization of enzymes or proteins on inorganic substrates also helps maintain structural integrity and function in less favorable environments. Mesoporous thin films are a suitable choice for enzyme supports due to their high surface areas (1000 m2g-1), large pore volumes (1.0mL g-1) and tunable pore diameters (10-300Å). The synthesis of mesoporous silica materials as thin films makes them attractive for use as membranes, low dielectric interlayers and the immobilization of proteins for optical biosensing. Specifically, the optical transparency of mesoporous thin film could allow for convenient signal transduction in fluorescing systems such as GFP.