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Analytical Chemistry Seminar

Date:
-
Location:
CP-208

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Dawn Kato will be presenting her exit seminar, titled Applications of Gas Chromatography/Mass Spectrometry and Capillary Electrophoresis for the Analysis of Lignocellulosic Biomass Pretreatment.

Abstract: The focus of this talk centers on the development and applications of gas chromatography/mass spectrometry and capillary electrophoresis methodologies to quantify monomeric compositions of the β-O-4 linkages in lignin.  Pretreatment is a required step in the utilization of lignocellulosic biomass for biofuels.  Lignin is the target of pretreatment because it hinders the accessibility of enzymes and chemicals to cellulose.  The effects of pretreatment are commonly assessed utilizing enzymatic saccharification and lignin assays.  However, these techniques do not elucidate the effects of pretreatment on the monomeric make up of lignin. 

The overarching hypothesis is that the quantification of monolignol composition will show changes in the lignin makeup due to pretreatment.  To test the hypothesis, a pretreatment, solution phase Fenton chemistry, was conducted on various lignocellulosic biomass feedstocks.  Enzymatic saccharification studies showed a significant increase in glucose production upon Fenton pretreatment, however, lignin assays did not show a significant decrease in lignin content. 

Project two aimed to synthesize analytical standards in order to develop a quantitative thioacidolysis technique.  The successful synthesis of the three arylglycerols were conducted utilizing and epoxidation reaction scheme which was hypothesized to produce a single diastereomer, as supported by GC/MS and chiral CE analysis.  Upon method development, a quantitative thioacidolysis GC/MS method was applied to untreated and Fenton treated biomass.  Results from this project revealed there was no significant change in the three lignin monomers.  To test the method validity, the quantitative thioacidolysis GC/MS method was applied to a pretreatment method known to degrade lignin, alkaline peroxide pretreatment.  The results of this project showed a significant change in monolignol concentrations upon alkaline peroxide pretreatment. 

Analytical degradative techniques, such as thioacidolysis, has traditionally assessed lignin as monomeric ratios.  However, upon alkaline peroxide pretreatment, no significant change was seen in the monomeric ratios, but there was a significant difference in all three monolignol concentrations.  These results support the overall hypothesis that changes in individual monolignol content upon pretreatment can be observed from quantification.  The works of these projects provide an analytical method which contributes to the elucidation of lignin.

Course Instructor: Dr. Jason DeRouchey