An Implantable Biosensor Platform Enabled by Novel Porous Oxide Protection of Electrochemical Aptamer Working Electrodes

University Of Cincinnati Main Campus, Cincinnati OH

Investigators

Abstract

Managing chronic diseases in the United States is the biggest cost to the health care system and is poised to worsen as the population ages. Not patients, not doctors, and certainly not insurance companies are satisfied with the complexity of care and patient outcomes for chronic diseases. However, improved care in chronic disease has without question been achieved with the wide-spread use of wearable monitoring of glucose for diabetics. The impact of continuous wearable monitoring has been so substantial for heart disease and for diabetes that there is already a commercial emergence of long-lasting implantable monitors for glucose and heart function. However, only a small number of measures are possible with implantable sensors due to the ultra-difficult requirement of the sensors having to last a year or more of continuous operation. This is unfortunate, because implanted monitors can in theory reduce costs (less trips to the doctor’s office for tests), improve patient outcomes by more timely and actionable data, and by virtue of their simplicity (almost no user effort) have greater impact on patient lifestyle choices. A need therefore exists for a new technology that can not only measure many types of molecules in the body, but do so with reliable operation for a year or more such that implantable use becomes practical and desirable. The specific objective of this project is to demonstrate the fundamental building blocks needed for molecular sensors to monitor inside the body for multiple years, and therefore enable the first ever implantable monitoring platform that is generalizable to multiple chronic diseases. The project work plan focuses on aptamer sensors, which place strands of DNA on an electrode, and the DNA captures and allows electronic measurement of molecules circulating throughout the body. These aptamer sensors essentially provide the same type of information achieved with a blood test at the doctor’s office, but instead will be measuring all the time inside the body. Making these sensors last long enough for implanted operation is a major challenge and is the specific scientific focus of this project. To enable more than one year of operation this project will stabilize the sensor surface with robust porous oxides with a goal of 1 month of reliable operation, then develop a device design with 12 sensors that are sequentially exposed at one-month intervals inside the body such that at least 12 months of operation is achieved. Achieving 12-month operation then opens the possibility for an implanted sensor, where patients and doctors have continuous access to health status and a simpler and more impactful way to manage a patient’s chronic disease. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.