Microneedle-based enzymatic biosensors for continuous glucose monitoring: A review of materials, architectures, and performance

Diabetes is a significant global health problem, affecting millions and necessitating effective management strategies, particularly through continuous glucose monitoring (CGM) technologies. Traditional glucose monitoring methods, such as finger piercing, are invasive and painful, while existing CGMs often suffer from issues like pain and latency. Microneedle-based enzymatic biosensors present a promising solution to these challenges, offering a minimally invasive alternative that can provide real-time glucose data. This review aims to critically examine the key components, design strategies, and performance metrics of microneedle-based glucose biosensors, based on literature published between 2013 and 2024. It will discuss the effects of needle master materials, surface modification layers, electrochemical cell designs, and protective membranes on performance. The paper will conclude by summarizing current challenges such as biocompatibility, long-term stability, and calibration, while indicating potential aspects for future research, including self-powering systems and multiple analyte detection.