Abstract: A method of detecting at least one of analyte in an environment (such as in breath) includes providing a structure including nanostructures in contact with titanium dioxide, applying electromagnetic radiation to the structure for a period of time, measuring at least one response and using the measured response to determine the presence of the analyte in the environment.

Abstract: A method of detecting at least one of analyte in an environment (such as in breath) includes providing a structure including nanostructures in contact with titanium dioxide, applying electromagnetic radiation to the structure for a period of time, measuring at least one response and using the measured response to determine the presence of the analyte in the environment.

Abstract: A method for preparing carbon allotrope based sulfide detectors comprising first functionalizing a carbon allotrope, such as a single-walled carbon nanotubes or graphene, with a solution of a polynuclear aromatic hydrocarbon-sulfonic acid, such as 1-pyrenesulfonic acid, followed by treatment with a metal, such as gold nanowires or cupric salt doped polyaniline, to give a metal-functionalized carbon allotrope, then drop casting the metal-functionalized carbon allotrope onto an inert surface, such as a silicon dioxide film on a silicon wafer having electrodes. Detection of sulfides may be by means such as photochemical or conductance methods. The hydrogen sulfide detectors may be used to detect and/or quantitate ppb and ppm levels of hydrogen sulfide in industrial settings or in detecting halitosis.