Development of a Multiplexed Electrochemical Biosensor for Real-Time Glucose and Lactate Detection

A multiplexed, highly sensitive, and stable electrochemical sensors has been developed for the detection of glucose and lactate in biological fluids, enabling early screening of calf diseases such as Bovine respiratory disease (BRD) and scour. The device incorporates an interdigitated microelectrode (IDE) array comprising on-chip working, counter, and reference electrodes. Glucose oxidase and lactate oxidase were immobilized in a platinum black/o-phenylenediamine/β-cyclodextrin polymer matrix on two separate working electrodes. For glucose sensing, an effective in-situ pH control method enabled by the IDEs was employed to optimize the pH for accurate detection. Both sensors demonstrated detection over a range of 0.05–2 mM with excellent linearity (R² ~ 0.99). COMSOL simulations and interference studies were conducted to evaluate the sensors potential for application in saliva.