Biosensors have also been developed from GaN nanowires: originally based off silicon nanowires, GaN nanowires provide large surface areas and high sensitivities for detecting biomolecules once functionalized. Devices for detecting streptavidin and lipids of the E Coli. membrane were developed. They displayed differences in conductivities upon binding with the target molecules. In order to induce specificity in the nanowire sensors, it was important to functionalize them beforehand. The nanowires were oxidized, and then reacted with 3-aminopropyltriethoxysilane and biotin. Specificity studies through fluorescence demonstrated that the sensor only bound to streptavidin rather than other proteins in bovine serum albumin. In order to clear the sensor for repeated usage, they were simply washed with an aqueous detergent solution. The conductance of the nanowire would be analyzed in order to determine the binding concentrations for practical usage. \cite{Williams_2014}