title: Supercritical fluid extraction and high-performance liquid chromatography-diode array-electrochemical detection of signature redox compounds from sand and soil samples.
abstract: A supercritical fluid extraction procedure and a chromatographic separation/detection method were developed for the detection of Earth-based microorganisms. After microbes in a sand or a soil sample were hydrolyzed in a diluted NH(4)OH/acetone solution, several redox compounds from bacteria could be effectively extracted with trimethylamine-modified supercritical CO(2) at 35 degrees C and 300 atm. These signature redox-active compounds were separated by a reversed-phase HPLC column in an ion-pair mode and then monitored with a diode array detector and an electrochemical detector. The analytical results demonstrated the feasibility of using the reported techniques to detect the chemical signature of life in barren desert sand samples.
authors.affiliation: Department of Chemistry, University of Idaho, Moscow, Idaho 83844, USA.
authors.forename: Qingyong
authors.initials: Q
authors.lastname: Lang
authors.forename: I Francis
authors.initials: IF
authors.lastname: Cheng
authors.forename: Chien M
authors.initials: CM
authors.lastname: Wai
authors.forename: Andrzej
authors.initials: A
authors.lastname: Paszczynski
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Crawford
authors.forename: Bruce
authors.initials: B
authors.lastname: Barnes
authors.forename: Tony J
authors.initials: TJ
authors.lastname: Anderson
authors.forename: Richard
authors.initials: R
authors.lastname: Wells
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Corti
authors.forename: Lisa
authors.initials: L
authors.lastname: Allenbach
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Erwin
authors.forename: Touraj
authors.initials: T
authors.lastname: Assefi
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mojarradi
mesh_terms: D001419:Bacteria / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D005486:Flavin Mononucleotide / Q000032:analysis; D005182:Flavin-Adenine Dinucleotide / Q000032:analysis; D006427:Hemin / Q000032:analysis; D010084:Oxidation-Reduction; D012256:Riboflavin / Q000032:analysis*; D012822:Silicon Dioxide / Q000737:chemistry; D012987:Soil / Q000032:analysis; D014451:Ubiquinone / Q000032:analysis
chemical_list: D012987:Soil; D014451:Ubiquinone; D005182:Flavin-Adenine Dinucleotide; D006427:Hemin; D012822:Silicon Dioxide; D005486:Flavin Mononucleotide; D012256:Riboflavin