Microfabricated capillary electrophoresis amino acid chirality analyzer for extraterrestrial exploration

Anal Chem. 1999 Sep 15;71(18):4000-6. doi: 10.1021/ac9903959.

Abstract

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.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acids / analysis*
  • Electrophoresis, Capillary / instrumentation
  • Electrophoresis, Capillary / methods*
  • Extraterrestrial Environment*
  • Fluorescein-5-isothiocyanate
  • Fluorescent Dyes
  • Stereoisomerism

Substances

  • Amino Acids
  • Fluorescent Dyes
  • Fluorescein-5-isothiocyanate