An analytical system-on-a-chip can be used as an analytical imaging device, for example, for detecting the presence of a chemical compound. A layer of analytical material is formed on a transparent layer overlying a solid state image sensor. The analytical material can react in known ways with at least one reactant to block light or to allow light to pass through to the array. The underlying sensor array, in turn, can process the presence, absence or amount of light into a digitized signal output. The system-on-a-chip may also include software that can detect and analyze the output signals of the device.