A Flow Injection Microdialysis Sampling Chemiluminescence System for in Vivo On-Line Monitoring of Glucose in Intravenous and Subcutaneous Tissue Fluid Microdialysates

Abstract

A novel flow injection on-line microdialysis system for in vivo monitoring of glucose in subcutaneous tissue fluid and blood is described. An implantable loop-type microdialysis probe was used for subcutaneous sampling, and a flow-through microdialyzer was used for intravenous sampling by pumping of the blood from the tested rabbit through the microdialyzer located outside the living system at a flow rate of 10 microL/min. The perfusion rate of the dialysate was 20 microL/min. The glucose in the dialysate was detected on-line with a flow injection chemiluminescence system after passing through an immobilized glucose oxidase reactor. The calibration of the detector system (including reactor) and monitoring of baseline drifts were performed simultaneously to improve the reliability of the monitoring process. The dialysate sample volume was 20 microL, and the sample throughout was 28 h-1. The variation of glucose level in subcutaneous tissue fluid and blood of the rabbits was monitored after the administration of glucose or insulin to demonstrate the favorable resolution and reliability of the system for in vivo on-line monitoring.