The present invention generally provides devices, systems, and methods for determination of one or more analytes. The analyte may be determined by monitoring, for example, a change in an electrical, optical, or other signal of a material (e.g., sensor material) present within the device, upon exposure to the analyte. The signal may be an electrical and/or optical property of the device. In some cases, devices described herein may be useful as sensors for the determination of analytes such as explosives, chemical warfare agents, and/or toxins.