Development of Astrobiological Molecularly Imprinted Polymer Sensors

Introduction: Molecular Imprinted Polymer (MIP) -based sensors are promising candidates for a variety of in-situ planetary astrobiological and geochemical mission profiles, and are currently being developed under NASA Grant #NNG05GM90G issued through the Astrobiology Science & Technology Instrument Development Program. MIP sensors are solid state, inherently small and low mass, and have low power and bandwidth requirements. They rely on direct detection of target molecular species, as opposed to pyrolysis products or other reactions. The more complex the target species, the more specific and exclusive the detection, but sensors for simpler forms are also possible using a variety of MIP-derived methods. Synthetic polymer coatings are robust and can be optimized for transportation in the space environment and conditions at target terrestrial and other planetary locations [1]. A wide range of target species can be detected directly by simple fiber optic, slideor chip-based detectors utilizing MIP sensors. Substrates are imprinted with the molecular signature of a particular target species. When the species is present, its molecular shape is a unique “key” that fits into the MIP “lock,” (Fig. 1) causing a change in the coating’s mass and light absorbing/emitting properties. The wavelength, magnitude, and/or rate of change of the reflected light indicates the presence and abundance of the target species and differentiates possible contaminants. MIP technology is intended as both a detection scheme, and a quantitative tool for measurement of potential astrobiologically significant chemistries and other molecular species of interest.