Microfabricated capillary electrophoresis amino acid chirality analyzer for extraterrestrial exploration.
Chiral separations of fluorescein isothiocyanate-labeled amino acids have been performed on a microfabricated capillary electrophoresis chip to explore the feasibility of using such devices to analyze for extinct or extant life signs in extraterrestrial environments. The test system consists of a folded electrophoresis channel (19.0 cm long x 150 microns wide x 20 microns deep) that was photolithographically fabricated in a 10-cm-diameter glass wafer sandwich, coupled to a laser-excited confocal fluorescence detection apparatus providing subattomole sensitivity. Using a sodium dodecyl sulfate/gamma-cyclodextrin pH 10.0 carbonate electrophoresis buffer and a separation voltage 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 were determined for amino acids extracted from the Murchison meteorite, and these values closely matched values determined by HPLC. These results demonstrate the feasibility of using microfabricated lab-on-a-chip systems to analyze extraterrestrial samples for amino acids.
Hutt
L D
LD
Department of Chemistry, University of California, Berkeley 94720, USA.
Glavin
D P
DP
Bada
J L
JL
Mathies
R A
RA
D000596:Amino Acids / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D005118:Extraterrestrial Environment; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D013237:Stereoisomerism
D000596:Amino Acids; D005456:Fluorescent Dyes; D016650:Fluorescein-5-isothiocyanate