NITRITE - SELECTIVE POTENTIOMETRIC SENSOR
Dana Vlascici, Elena Maria Pica, Cosma - Fagadar Eugenia, Bizerea Otilia, Costisor Otilia, Cosma Viorica
This invention concerns a nitrite-selective potentiometric sensor used to measure the nitrite concentration in samples of various origins, such as environment pollution, food control, scientific research, etc. The sensor has a body made of PVC bar, which is provided at its base with a nitrite selective membrane on a conductive support. The membrane consists of a PVC plasticized with ortho- nitrophenyloctyl ether (o-NPOE), where the ionophore tetraphenyl porphyrin - cobalt chloride (CoTPPCl) and the lipophil additive trioctylmethylammonium chloride (TOMACl) are included. The sensor operational principle is based upon the measurement with an ionmeter/millivoltmeter devise of the potential at the surface of the nitrite-sensitive membrane, determined by the concentration of nitrite ions in the solution where
the sensor is immersed.