Cytokine proteins are one of the most important early indicators of infection and immune response, and therefore serve as an excellent diagnostic tool for monitoring health. The objective of this project is to develop an easy-to-use handheld diagnostic sensor, with the NSBRI Smart Medical Systems Team, for the rapid detection of several cytokine levels in saliva. This lightweight and noninvasive monitor for the routine detection of cytokine levels would play an important role in astronaut healthcare during long-duration space missions and would be an immediate asset to the medical community on Earth.

Current affinity-based technologies used to detect cytokines, such as the enzyme-linked immunosorbent assay (ELISA), are time-consuming and labor-intensive, requiring trained technicians and bulky equipment not suitable for space flight. The specific aim of this project is to develop a miniature immunosensor that will deliver fast and sensitive results within minutes.

This prototype will contain a microfluidic consumable integrated with automated sample preparation and a reusable optical readout device. I will accomplish this aim by optimizing the sensors three state-of-the-art key features:

1. Adaptation of an affinity-based assay that uses up-converting phosphor (UCP) reporter technology (SRI International, USA) for the sensitive detection and quantification of several cytokine profiles;
2. Modification of micro-pillared capillary structures on the microfluidic chip (mic, Sweden) to provide direct fluidic control over critical assay parameters, and;
3. Development of an optical detector to detect and amplify UCP signal on the microfluidic chip. This research will produce a convenient and affordable diagnostic test that could also be used to implement virtually any affinity-based assay on a common platform for Earth and space-based medical care.

Earth-based Applications of Research Project
The Earth-based applications of this research project are the development of diagnostic equipment to monitor infection and immune response in clinical point-of-care situations. UCP technology integrated with an mic microfluidic platform promises a smaller, faster, easy-to-use biosensor that will integrate multiple steps into a single, streamlined application to detect multiple analytes in parallel, which is also simple and robust. This immunosensor will have important implications for human health care here on Earth. The sensor will also be adaptable to other clinical diagnostic applications for monitoring health and disease such as cardiac enzymes and pathogen biomarkers.

NASA Task Book Entry