Analysis of carbonaceous biomarkers with the Mars Organic Analyzer microchip capillary electrophoresis system: Aldehydes and ketones

Abstract

A microchip CE method is developed for the analysis of two oxidized forms of carbon, aldehydes and ketones, with the Mars Organic Analyzer (MOA). Fluorescent derivitization is achieved in ∼ 15 min by hydrazone formation with Cascade Blue hydrazide in 30 mM borate pH 5-6. The microchip CE separation and analysis method is optimized via separation in 30 mM borate buffer, pH 9.5, at 20°C. A carbonyl standard consisting of ten aldehydes and ketones found in extraterrestrial matter is successfully separated; the resulting LOD depends on the reactivity of the compound and range from 70 pM for formaldehyde to 2 μM for benzophenone. To explore the utility of this method for analyzing complex samples, analyses of several fermented beverages are conducted, identifying ten aldehydes and ketones ranging from 30 nM to 5 mM. A Martian regolith simulant sample, consisting of a basalt matrix spiked with soluble ions and acetone, is designed and analyzed, but acetone is found to have a limited detectable lifetime under simulant Martian conditions. This work establishes the capability of the MOA for studying aldehydes and ketones, a critical class of oxidized organic molecules of interest in planetary and in terrestrial environmental and health studies.

Analysis of Carbonaceous Biomarkers with the Mars Organic Analyzer Microchip Capillary Electrophoresis System: Carboxylic Acids

“…The microdevices were prepared as previously described (Skelley and Mathies, 2003;Skelley et al, 2005Skelley et al, , 2006Skelley et al, , 2007Chiesl et al, 2009;Stockton et al, 2009aStockton et al, , 2009bStockton et al, , 2010 and will be briefly discussed here. A sacrificial layer of polysilicon was deposited on a 10 cm borofloat glass wafer.…”

“…Cyclodextrin-assisted lCE separations were used to detect partsper-billion levels of polycyclic aromatic hydrocarbons in a variety of environmental and Mars simulant samples (Stockton et al, 2009). Cascade Blue hydrazide (CB) derivatization enabled MOA detection of aldehydes and ketones from samples ranging from fermented beverages to a basaltic martian regolith simulant (Stockton et al, 2010). An important next goal for the MOA is the development of methods to analyze carboxylic acids.…”

Implementation of microchip electrophoresis instrumentation for future spaceflight missions

“…developed during the subsequent years, greatly expanding the analytical capabilities of the technology [31][32][33][34][35][36][37][38][39]. Most recently, our laboratory demonstrated the analysis of fatty acids onchip with use of nonaqueous solvents [38] and the potential of this method to characterize microbial communities.…”

“…ME-LIF is an extremely powerful tool to search for these nonstatistical distributions of molecular properties present in a sample, by separating a mixture into its components, identifying them, and quantifying their levels. ME-LIF has been used to investigate a variety of organics that can serve as biomarkers, including amines [31,32], amino acids [32,33], organic acids [34], aldehydes and ketones [35], nucleobases [36], polyaromatic hydrocarbons [37], fatty acids [38], and thiols [39]. Depending on the geochemical context of the sample analyzed, these molecular classes can inform us of the potential for biological processes in the location under study.…”

Detection of Biomarkers in Gas Plumes Using a Multi-Spectral Camera in the Proposed Enceladus Orbiter Mission (NASA)

“…dwutlenku węgla (CO 2 ) i metanu (CH 4 ) w atmosferze Marsa [12]. Oparty na zjawisku elektroforezy kapilarnej Mars Organic Analyzer został zaprojektowany do detekcji dwóch utlenionych postaci węgla: aldehydów i ketonów [20]. Detekcja biomarkerów prowadziła zawsze do analizy lokalnych warunków geologicznych i fizykochemicznych w celu wykluczenia innego źródła biomarkera niż źródło biogeniczne.…”