Non-enzymatic glucose sensing on copper-nickel thin film alloy

Abstract

A simple and cost efficient glucose sensor was constructed using 3D printing having as active material a copper-15 at.% nickel thin film thermally co-evaporated on copper plated circuit boards. The glucose detection in alkaline solution was studied in detail by cyclic voltammetric and chronoamperometric measurements. The sensor suitability for being used in both quantitative and qualitative glucose detection was demonstrated and calibration of its response to various amounts of glucose revealed two linear regimes with different sensitivities. Glucose levels between 0 and 10mM are most efficiently quantified as indicated by an amperometric signal increase of 240μAcm−2 for each 1mM increase of glucose concentration. The potentiostatic stability of the sensor was evaluated and its complete insensitivity after 7h was solely attributed to the irreversible transformation of glucose into gluconolactone. A sensor life time of 20 cycles was demonstrated during potentiodynamic cycling when the sensor response remains constant at its maximum level. The magnitude of possible glucose quantification errors were evaluated as interferences induced by additions of ascorbic and uric acids. A worst case scenario of 96 % accuracy of glucose levels quantification was demonstrated using 25 times higher concentrations of interfering substances as compared to the glucose level.