Recent advancement in electrode materials and fabrication, microfluidic designs, and self-powered systems for wearable non-invasive electrochemical glucose monitoring

Due to the ever-increasing number of diabetic people globally, continuous monitoring of glucose became an increasingly important subject in the field of point-of-care diagnosis. However, there are still many shortcomings of current diagnostic approaches, including materials and device design, comfort, and stability of device performance. Here, brief, albeit comprehensive, information on current trends of using novel materials and techniques to fabricate wearable electrochemical biosensors for continuous and non-invasive glucose monitoring are provided. Flexible materials as versatile substances to fabricate wearable glucose biosensors used in various body fluids, including sweat, interstitial body fluid (ISF), saliva, and tear, are studied. Moreover, current electrode fabrication methods such as printing, laser induction, photolithography, electrodeposition, seed mediation, and dealloying to construct porous and one-dimensional material with interesting mechanical properties are explored. Microfluidic designs and self-powered systems for better control and storage of the body fluids and decreasing the weight, size, and cost of the wearable electrochemical glucose devices are also studied in this review. The overall progress made to date in building such conceptualized efforts for real-time, wearable continuous monitoring of glucose and the future of the field is briefly discussed. This review has benefits compared to previous reviews, as recent developments in continuous glucose monitoring have interestingly combined with two other amazing and innovative subjects of biosensing, including microfluidics and self-powered systems.