Homemade Bienzymatic-Amperometric Biosensor for Beverages Analysis

• Published in: Journal of chemical education Vol. 84; no. 4; pp. 677 - 680
• Main Authors: Blanco-López, M. C, Lobo-Castañón, M. J, Miranda-Ordieres, A. J
• Format: Journal Article
• Language: English
• Published: Easton Division of Chemical Education 01.04.2007; Division of Chemical Education of the American Chemical Society; American Chemical Society
• Subjects: Analytical chemistry; Beverages; Biosensors; Chemistry; College Science; DIY; Do it yourself; Electrical measurement; Glucose; Laboratory Equipment; Laboratory Experiments; Measurement Equipment; Measurement techniques; Science education; Science Equipment; Science Experiments; Science Instruction; Scientific apparatus & instruments; Soft drinks; Teaching methods; Undergraduate Study; Hands-On Learning / Manipulatives; Upper-Division Undergraduate; Analytical Chemistry; Bioanalytical Chemistry
• ISSN: 0021-9584; 1938-1328
• DOI: 10.1021/ed084p677

In this experiment students construct an amperometric glucose biosensor and use it to determine the glucose concentration in soft drinks. This experiment is appropriate for an advanced instrumental course; however, it could be adapted to elementary levels. The design is based on the immobilization of the glucose oxidase and horseradish peroxidase enzymes with a redox mediator (ferrocene) in a carbon paste electrode. The glucose concentration is directly related to the cathodic current yielded by the oxidized form of the mediator obtained in the enzymatic reactions. The students use cyclic voltammetry to optimize sensor design and performance, and analytical characterization and glucose determination is carried out amperometrically. The preparation of the sensor is simple, quick, and can be carried out with inexpensive materials. The challenge of constructing biosensing devices and the good results typically obtained are very stimulating for the undergraduate students.