Testing an Automatic Glucose Monitoring System for Online Bioprocess Monitoring

Abstract

Glucose is one of the most vital nutrients in living organisms, and its monitoring in bioprocesses and healthcare applications is essential. Enzymatic sensors are the most popular method for measurements; however, periplasmic binding proteins have been investigated recently in biosensing applications due to their high sensitivity, which allow microdialysis devices to collect samples in a non-invasive manner that would replace the current bulky and expensive glucose monitoring systems. Binding proteins were used as biosensors by treating them with an environmentally-sensitive fluorophore that measures the conformational change of the protein through fluorescence when it binds to glucose. In order to make the process continuous, a sensor prototype was built to measure glucose through glucose binding protein (GBP) in reusable microfluidic columns. The goal of this study was to tune the sensitivity of the glucose sensor by changing the sampling surface area through which glucose is collected across different sampling flow rates in order to broaden the detection range of the machine. The fluorescence response showed that there are possible limitations to the measuring and sampling portions of the machine that need to be further investigated to better optimize it as a versatile biochemical analyzer.