Life Detection within Planetary Exploration: Context for Biosensor and Related Bioanalytical Technologies

Is there life on Mars? This is a major question within the scientific community and one that also has broad appeal within the general community. To date, only three missions have attempted to look for life on Mars—the two NASA Viking missions in the mid-1970s and the recent UK-led Beagle 2 mission. In all cases no life was detected—in the case of Beagle 2 due to a nonnominal landing event. Our current view of Mars is that historically there was the potential for life to have existed in the Maritain environment and even the possibility of there being current life on Mars. New analytical techniques are therefore being considered for the next generation of Mars rovers and landers to search for evidence of such life. Biosensors in the form of antibody microarray devices are being considered by a number of groups as potential instruments to detect evidence of life in situ in the form of molecular biomarkers within the Martian surface and near subsurface. Such research is at an early stage of development within the context of development of flight-qualified instrumentation. Given the extreme environments that will be encountered during various phases of a typical Mars mission, careful consideration of the effect of radiation exposure, instrument sterilization, minimization of instrument contamination, long-term storage, and various thermal environments will be required in instrument development programmes. It is hoped that pushing the development of biosensor technology for life detection in a planetary exploration context will allow both the eventual answer of a fundamental question within society and also provide new developments and approaches that will benefit existing biosensor developments in other areas of application. Keywords: astrobiology; immunosensor; antibody arrays; life on Mars