In some embodiments of the invention, encapsulated semiconducting nanomaterials are described. This structure is then annealed at low temperatures to form a metal doped semiconductor having greater than about 1\xd71020 dopant atoms per cm3 of silicon. The device can also be used to sample fluid. The latching assembly includes a lacking fastener and a coil spring, wherein the latching assembly is effective to nail the removable panel into the housing through the first mounting portion and the second mounting portion. A light unit with high light output requiring limited space is developed with the present invention.