Low-cost microfluidic electrochemical paper-based device to detect glucose

Continuous monitoring of the level of glucose is essential to maintain the health of a diabetic patient. The use of invasive methods to obtain blood samples to detect glucose is the current method, but such methods may not be preferred by patients. Non-invasive methods such as the determination of glucose based on saliva or sweat can be preferred by patients for continuous monitoring. A low-cost electrochemical microfluidic paper-based analytical device (µPAD) suitable to monitor glucose levels using sweat and saliva is introduced. This device is extremely low-cost due to the use of a paper matrix and varnish for the fabrication of paper. Pseudo-reference stainless steel is used with a working electrode anodized using sodium potassium tartrate tetrahydrate for the development of a three-electrode system. Cyclic voltammetric-based analysis of glucose with µPAD produced a linear response in the working range of 1-10 mmol dm^-3 with a limit of detection of 0.058 mol dm^-3. The detection of diabetic conditions using saliva and sweat is possible using the device by correlating to the blood glucose levels using prior literature data.