Monitoring Radiation-Induced DNA Degradation
PI: Howard G. Levine, NASA/Kennedy Space Center
PI: Howard G. Levine, NASA/Kennedy Space Center
The MEMS (Micro‐Electro-Mechanical Systems) Radiation project is developing a miniaturized microfluidic (lab‐on-a‐chip) device that is designed to monitor DNA damage, in real‐time, resulting from radiation exposure in space. The instrument under development will (a) use the polymerase chain reaction (PCR) to amplify DNA, (b) thermally image the micro‐device to monitor thermal gradients for proper thermal exposure, and (c) use fluorescent imaging to monitor radiation‐induced changes in DNA composition. The ultimate goal is to help understand the details of radiation exposure in space and potentially serve as a radiation rapid warning device for astronauts.
- TA06 Human Health, Life Support and Habitation Systems
- TA10 Nanotechnology
The project's goal is to continuously pump DNA within a buffer/oil carrier solution into a microfluidic chip along with a Polymerase Chain Reaction (PCR) mixture. The mixture passes through a temperature gradient PCR microchannel consisting of 40 DNA amplification cycles. Thermal cycling occurs as the mixture travels serially through the serpentine microchannel. Precise temperature regulation is thus key to the device's operation, necessitating the assessment of thermal control in the convectionless microgravity environment.
This project leverages research activity with university partners that are leaders in micromanufacturing (LaTech). The proposed effort will take a technology currently at TRL-5 and through the proposed testing under parabolic flight conditions elevate it to TRL-6 by demonstrating its functionality under microgravity conditions. After a cubesat/ISS flight (targeting 2014), the technology will be further elevated to TRL-7.
Commercial applications of this technology pertain to the development of miniaturized medical equipment such as diagnostic instruments used by emergency responders and personalized caregivers.
The three primary goals of the Sept. 2011 parabolic flight campaign were to: (1) demonstrate the microfluidic slide's fluid circulation within various gravity environments (microgravity, 2G, and transitional gravity environments), (2) study the effects of the microgravity environment on the thermal gradients within the micro device as it can possibly have negative effects on PCR when proper thermal settings are altered, (3) evaluate whether a newly fabricated prototype camera is capable of meeting all project requirements in a microgravity environment before it is implemented in its final cubesat/ISS configuration.
The MEMS Radiation hardware was loaded inside the FASTRACK payload platform using Middeck Locker Equivalent (MLE) half trays for safe stowage during flight operations. The experimental setup included a Unit Control Box that housed the system's thermal controls, temperature display, fluid pump and manual system control. A microfluidic chip assembly with Minco film heaters was alternately imaged by the FLIR thermal imaging camera and a Bionetics designed prototype fluorescent imaging system on consecutive flight days.
The goal of this project is to provide a series of enhanced biological research instruments for use both on Earth and by astronauts in space. To be usable in space, this equipment must be small, light, and require only minimal electricity. Also, it must be able to work in the absence of gravity. On Earth, heat rises because of gravity. Without gravity, heat does not naturally dissipate, and can create problems with equipment overheating. Therefore, in addition to being small and low-power, research equipment designed for space utilization must also be immune to these overheating issues. We have created a device to perform genetic analyses that satisfies all of these conditions. Through the Flight Opportunities Program, we were able to test and validate the system in microgravity. Our testing indicates that the temperature of the most essential components will not rise by more than 1°C when used in an extended microgravity environment.
With this successful flight validation we can continue our instrumentation development with confidence. Only three years ago, this instrument was just a plan and a goal. Hopeful for such an opportunity as this parabolic flight campaign, we worked to integrate all of the subsystems together for this flight: the mechanical structure, the temperature control and isolation, the microfluidic device and pumping, and the fluorescent imaging components. Our next objective is to further develop the functionality of the system in order to increase its usability in the space environment.
The validation of the temperature control of this system in true reduced gravity removed the greatest operational risk associated with space flight. This could not have been accomplished without the support of the Flight Opportunities Program, which provided the opportunity to validate the technology through the microgravity conditions provided on a series of parabolic flights. With this critical question about heating now resolved, we can proceed toward space deployment with a greater confidence that we will be able to provide astronauts and researchers this advanced bioanalytical capability.
Selection DateAFO1 (May 2011)
Program StatusTesting Complete
Current TRL (?)TRL 5
- 3 Parabolic
PIHoward G. Levine
PartnersThe KSC Engineering Support Contract
Louisiana Tech University