The efficacy of formation of different nanocomposites of germania was examined in the presence of several biocatalysts such as sequenced peptides and specific amino acids to selectively mineralize germania. Studies related to germanium dioxide are relatively uncommon even though many properties of germanium are similar to those of silicon and thus open new avenues for investigation at the nano level. The shapes and sizes of the nanocomposites formed were found to be dependent upon the pH of the growth solutions, temperature, concentrations of the precursors and the types of precursors used. In some cases highly crystalline materials with high surface areas were formed. The growth of the nanocomposites was monitored by dynamic light scattering (DLS), transmission electron microscopy and atomic force microscopy. Calcination of the products led to highly crystalline materials. The optical properties of the nanocomposites were characterized by fluorescence, and ultraviolet-visible spectroscopy. Depending upon the types of the nanocomposites prepared, we also examined several applications of the nanocomposites such as antibacterial activities, sensors and catalysis. We have further extended our methods for preparation of diverse nanocomposites comprising of metal-doped silicate materials, alumina and titanium oxide extensively due to their enhanced properties and applications. Such new materials could be potentially useful for the development of highly sensitive sensors, catalysts and optical devices.