Microfabricated capillary electrophoresis amino acid chirality analyzer for extraterrestrial exploration

Chiral separations of fluorescein isothiocyanate-labeled amino acids have b een performed on a microfabricated capillary electrophoresis chip to explor e the feasibility of using such devices to analyze for extinct or extant li fe signs in extraterrestrial environments. The test system consists of a fo lded electrophoresis channel (19.0 cm long x 150 mu m wide x 20 mu m deep) that was photolithographically fabricated in a 10-cm-diameter glass wafer s andwich, coupled to a laser-excited confocal fluorescence detection apparat us providing subattomole sensitivity. Using a sodium dodecyl sulfate/gamma- cyclodextrin pH 10.0 carbonate electrophoresis buffer and a separation volt age of 550 V/cm at 10 degrees C, baseline resolution was observed for Val, Ala, Glu, and Asp enantiomers and Gly in only 4 min. Enantiomeric ratios we re determined for amino acids extracted from the Murchison meteorite, and t hese values closely matched values determined by HPLC. These results demons trate the feasibility of using microfabricated lab-on-a-chip systems to ana lyze extraterrestrial samples for amino acids.