Patent ID: 8506902

Claim:
A colorimetric sensor for measuring one or both of the presence and concentration of an organic solvent, said colorimetric sensor comprising: a substantially continuous reflective layer that is a metal selected from aluminum, chromium, gold, nickel, and silver; a detection layer over the substantially continuous reflective layer, said detection layer comprising a hydrophobic inorganic material having a network of pores; and a substantially continuous semi-reflective layer over the detection layer, the semi-reflective layer having an index of refraction different from the index of refraction of the detection layer, wherein at least a portion of the substantially continuous semi-reflective layer is permeable to the organic solvent, wherein upon exposure of the colorimetric sensor to the organic solvent, the organic solvent permeates through the semi-reflective layer into the detection layer and the organic solvent changes a refractive index of the detection layer.