Transdermal Microneedle Array-based Sensor for Real Time Continuous Glucose Monitoring

Abstract

We fabricated a low cost, low power consuming and easy to use continuous glucose monitoring system in this study. The transdermal sensor consists of an electrochemical sensing unit, a signal-processing unit and a power supply unit. The electrochemical sensing unit comprises an array of microneedle. The transdermal sensor is minimally invasive which can pierce the upper layer of the skin. Glucose Oxidase (GOx) was immobilized on the Au microneedle surface by forming self-assembled monolayer with 3-Mercaptopropionic acid (MPA). The GOx immobilized microneedle will be used as a subcutaneous glucose sensor to detect the glucose levels in interstitial fluid (ISF). The cyclic voltammetric studies and the transdermal sensing unit developed in this study were able to detect glucose with linear range of 30 mg dL-1 to 400 mg dL-1. The results showed that the prepared sensor can be used to sense glucose in subcutaneous tissues and are applicable for real-time continuous glucose monitoring system.