Polyvinyl alcohol-cellulose composite: a taste sensing material

There are reports of fabrication of taste sensor by adsorbing lipids into Millipore filter paper. With this lipid based sensor, it has been found that the taste sensing efficiency of membrane can be remarkably improved. We have made an attempt to prepare taste sensor material by using functionalized polymer without any lipid. PVA-cellulose composite has been modified to use as the sensor material. The research work covers polymer membrane preparation, morphology study and structural characterization of the membrane and study of the taste sensing characteristics of this membrane for five different taste substances. PVA-cellulose composite membrane was modified by phosphorylation with POCl₃. FTIR spectroscopic analysis, XRD analysis and SEM were done to get an idea about the structure and morphology of the prepared phosphorylated PVA-cellulose composite membrane. The sensor characteristics like temporal stability, response stability, response to different taste substances, and reproducibility of sensing performance were studied using phosphorylated PVA-cellulose composite membrane. Sensor device prepared with this membrane has shown distinct response patterns for different taste substances in terms of membrane potential. Threshold concentrations of phosphorylated PVA-cellulose composite membrane for HCl, NaCl, Q-HCl, sucrose and MSG are 0001 mM, 0.001 mM, 0.001 mM, 0.001 mM and 0.009 mM, respectively. The threshold concentrations are below human threshold concentrations. Membranes also showed characteristic response patterns for organic acids like acetic acid, citric acid, formic acid etc, mineral acids like HCl, H₂SO₄ and HNO₃ salts, bitter substances, sweet substances and umami substances. Sensor device prepared with this membrane has excellent shelf life.