Electrosynthesized non-conducting polymers as permselective membranes in amperometric enzyme electrodes: a glucose biosensor based on a co-crosslinked glucose oxidase/overoxidized polypyrrole bilayer

• Published in: Biosensors & bioelectronics Vol. 13; no. 1; pp. 103 - 112
• Main Authors: Guerrieri, A., De Benedetto, G.E., Palmisano, F., Zambonin, P.G.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 1998; Elsevier Science
• Subjects: Amperometric sensors; Animals; Bioassay; Biological and medical sciences; Biosensing Techniques; biosensor; Biosensors; Biotechnology; Cattle; Conductive plastics; Crosslinking; enzyme co-crosslinking; Enzyme immobilization; Enzymes, Immobilized; flow-injection analysis; Fundamental and applied biological sciences. Psychology; glucose; Glucose - analysis; Glucose Oxidase; Glucose sensors; Humans; Methods. Procedures. Technologies; overoxidized polypyrrole; Polymers; Pyrroles; Sensitivity and Specificity; serum; Synthesis (chemical); Various methods and equipments; glucose; biosensor; overoxidized polypyrrole; enzyme immobilization; flow-injection analysis; serum; enzyme co-crosslinking; Glucose oxidase; Enzyme; Crosslinking; Glucose; Enzyme electrode; Biosensor; Amperometry; Serum; Oxidoreductases; Immobilized enzyme; Pyrrole polymer; Quantitative analysis; Flow injection
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/S0956-5663(97)00064-X

A glucose amperometric biosensor based on glucose oxidase immobilized on an overoxidized polypyrrole (PPy ox) platinum modified electrode, by glutaraldehyde co-crosslinking with bovine serum albumine, is described. The advantages of covalent immobilization techniques (e.g. high loading and long-term stability of the enzyme) are coupled with the excellent interferent rejection of electrosynthesized non-conducting polymers. The sensor showed an apparent Michaelis-Menten constant of 16 ± 0·8 mM, a maximum current density of 490 μA/cm 2 and a shelf lifetime of at least 3 months. Ascorbate, urate, cysteine and acetaminophen at their maximum physiological concentrations produces a glucose bias in the low micromolar range. Flow-injection response was linear up to 20 mM glucose with typical sensitivy of 84·0 ± 1·5 nA/mM. The sensor was tested for glucose determination of untreated serum samples from both normal and diabetic subjects; results of amperometric assay compared well with those obtained by a standard enzymatic-colorimetric method.