Monoenzymatic lipase potentiometric biosensor for the food analysis based on a pH sensitive graphite-epoxy composite as transducer

Abstract

In this paper the development of a potentiometric biosensor based on the use of the enzyme lipase immobilized in a Nafion membrane on a graphite-epoxy transducer is reported. This device has been used to quantify triglycerides in food samples from the aqueous extracts obtained by emulsion with Arabic gum. The proposed methodology does not present significant differences with the spectrophotometric determination used as contrast. This work constitutes the first report of a potentiometric biosensor based on the detection of changes of pH using a graphite-epoxy composite transducer and the first potentiometric triglyceride biosensor which is not based in ISFET transducers. The methodology designed is a simple and inexpensive alternative that minimizes the use of organic solvents without affecting the precision and accuracy of the analysis in complex food samples such as butter, chips and pastries.