A chemically differentiated sensor array system includes a plurality of environmentally-gated transistors and an environmental gate, wherein the environmental gate includes a liquid solution and each environmentally-gated transistor includes a drain, a source, and a Carbon-based substrate channel, the drain electrically couples to a first location on the substrate channel, the source electrically couples to a second location on the substrate channel separated by a gap from the first location on the substrate channel, the environmental gate covers and contacts the substrate channel, a first insulating layer covers and separates the drain from the environmental gate, and a second insulating layer covers and separates the source from the environmental gate.