Colorimetric polymer sensors for smart packaging

Nowadays, consumers can estimate the condition of packaged foods only by checking expiration date on label. However, this approach is inefficient when it comes to assessing actual edibility fresh products, since events that accelerate onset degradation phenomena, such as a rise in temperature, cannot be continuously assessed. In context, detection different parameter, low concentration amines, reveal processes. Here, colorimetric photonic multilayer sensor reported for detecting amine concentrations suitable sealed packages. The consists alternating layers poly(N-vinylcarbazole) and polyacrylic acid, its response based selective interaction between latter amines. This causes polymer swell introduce disorder into photon structure, resulting fading bright color. Since reaction these systems usually reversible, manipulation or false readings are possible due inapt sealing package. It shown activation carboxylic acid residues sensitive with N-hydroxysuccinimide produces an irreversible vapor 3 parts per billion.