Update on Implantable Sensors for Metabolic Monitoring

Overview

The document is a final report on the project titled "Microfabricated Multianalyte Sensor Arrays for Metabolic Monitoring," conducted by Dr. Michael V. Pishko at Pennsylvania State University, covering the period from August 15, 2004, to August 14, 2007. Funded by the U.S. Army Medical Research and Materiel Command, the project aimed to develop advanced sensor technologies for real-time metabolic monitoring, particularly focusing on glucose and lactate levels.

The report outlines the fabrication of glucose sensor arrays on gold electrodes using flexible polyimide sheets. The sensors were created through a process involving the cross-linking of glucose oxidase and redox polymers via UV-initiated free radical reactions. The methodology included conventional silicon fabrication techniques, such as mid-UV photolithography, to create five-element array microdisks. Active glucose oxidase was immobilized within photochemically polymerized hydrogels, allowing for effective entrapment on the array electrodes.

The performance of the fabricated microarray sensors was evaluated using cyclic voltammetry, demonstrating individual addressability and minimal cross-talk between adjacent elements. The sensors exhibited a linear response within the biological range, making them suitable for practical applications in metabolic monitoring. Additional electrochemical methods, including amperometry and square wave voltammetry, were employed to further assess the sensors' capabilities.

The report also discusses lactate sensors and their design, as well as the results of animal testing conducted to validate the effectiveness of the sensor arrays. Key research accomplishments and reportable outcomes are highlighted, showcasing the potential impact of these technologies on clinical and military applications.

In conclusion, the document emphasizes the significance of developing reliable, real-time monitoring systems for metabolic parameters, which can enhance patient care and operational effectiveness in military settings. The findings contribute to the broader field of biosensors and metabolic monitoring, paving the way for future research and development in this critical area. The report is approved for public release, ensuring that the knowledge gained can be shared with the scientific community and beyond.