Devices, systems and methods for detecting molecules in a solid state using UV lights in a dry condition are provided. Interaction between a plurality of molecules, a conformational change of a molecule, a size difference between a plurality of molecules and a presence of a molecule can be detected in a dry environment by measuring a light absorption in at least one of light transmission mode and light reflection mode. In a preferred embodiment, the measurement of a light absorption is performed at a wavelength of ultraviolet light between 260 nm and 285 nm.