Microchip capillary electrophoresis instrumentation for in situ analysis in the search for extraterrestrial life

Abstract

The search for signs of life on extraterrestrial planetary bodies is among NASA's top priorities in Solar System exploration. The associated pursuit of organics and biomolecules as evidence of past or present life demands in situ investigations of planetary bodies for which sample return missions are neither practical nor affordable. These in situ studies require instrumentation capable of sensitive chemical analyses of complex mixtures including a broad range of organic molecules. Instrumentation must also be capable of autonomous operation aboard a robotically controlled vehicle that collects data and transmits it back to Earth. Microchip capillary electrophoresis (μCE) coupled to laser-induced fluorescence (LIF) detection provides this required sensitivity and targets a wide range of relevant organics while offering low mass, volume, and power requirements. Thus, this technology would be ideally suited for in situ studies of astrobiology targets, such as Mars, Europa, Enceladus, and Titan. In this review, we introduce the characteristics of these planetary bodies that make them compelling destinations for extraterrestrial astrobiological studies, and the principal groups of organics of interest associated with each. And although the technology we describe here was first developed specifically for proposed studies of Mars, by summarizing its evolution over the past decade, we demonstrate how μCE-LIF instrumentation has become an ideal candidate for missions of exploration to all of these nearby worlds in our Solar System.

Implementation of microchip electrophoresis instrumentation for future spaceflight missions

“…This system used a hybrid microchip with integrated pneumatic valves for fluidic manipulations of liquid solutions prepared and supplied by a human operator, as described earlier [63]. The progression of this and related hardware has been discussed in detail in two previous reviews from our laboratory [81,82]. Simultaneously, SCWE technology was being developed by Grunthaner and Amashukeli at JPL (Fig.…”

“…The ME-LIF system we have developed which integrates all required ME-LIF subsystem features and functionality is the Chemical Laptop [82], shown in Fig. 13b during a recent validation study where we demonstrated amino acid analysis using the system in the field.…”

A review of microdialysis coupled to microchip electrophoresis for monitoring biological events

“…In 2005, Culbertson et al developed a stand-alone ME-LIF device for the detection of amino acids [113]. More recently, Peter Willis’ lab has developed a microchip electrophoresis system with LIF detection for deployment to other planets [114-116]. Additionally, our lab is currently developing a portable miniature LIF detection system for use with on-line microdialysis-microchip electrophoresis [117].…”

Determination of fluoroquinolone antibiotics by microchip capillary electrophoresis along with time-resolved sensitized luminescence of their terbium(III) complexes

“…Also, the potential usefulness of this technique for in situ analysis in the research for extraterrestrial life has been discussed [9]. A limitation of most MCE methods is their scarce practical application, which can be explained by their relatively poor sensitivity.…”