Patent attributes
A printed gas sensor, comprising a metalloporphyrin dye, has first and second modes, and a nanoporous carrier material comprising a plurality of particles measuring less than 5 μm; the particles have a plurality of pores, the pore size in the range 5-50 nm, wherein the metalloporphyrin dye is bound to the nanoporous carrier material. The disclosure further comprises a method of preparing a gas sensing composition for detection of food status and a digital expiry date device system, which comprises a packaging material with inner and outer surfaces; a first transponder disposed on the inner surface and a second transponder disposed on the outer surface. A sensor portion is electrically connected to the first transponder for detecting food status and communicating the status to the second transponder. The sensor portion comprises a metalloporphyrin dye which configures an impedance change upon binding with an gaseous analyte, and a printed numerical array.
