Abstract
In this experiment, we have developed the extracorporeal tissue glucose monitoring system by applying the tissue microdialysis technique, as an alternative way of long-term tissue glucose monitoring system. Briefly, the principle of this system is a dialysis hollow fiber implanted in the subcutaneous tissue, which is perfused with saline solution. Glucose concentrations in dialysate are measured continuously with a needle-type glucose sensor extracorporeally. With hollow fibers, Eval C5 and Cuprophan, glucose concentrations in dialysate were inversely proportional to perfusion rate and were proportional to fiber length. With hollow fiber length 15mm and perfusion rate 150μl/hr, a linear response between glucose concentrations in medium and in dialysate was obtained from 0 to 500mg/100ml glucose. In this condition, recovery of glucose with Eval C5 was 13%, and with Cuprophan was 330. The recovery of glucose was fairly constant for 4 days in the solution with albumin(3 and 5g /100ml). In vivo animal experiments, the subcutaneous tissue glucose concentrations measured by this method could nicely follow to the changes in blood glucose excursions. It is therefore concluded that this monitoring system based on subcutaneous tissue dialysis is reliable and stable at least for 4 days for glucose sensing in vivo, and can be applied as measuring system for wearable artificial endocrine pancreas.
