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Polyelectrolyte-Functionalized Nanofiber Mats Control The Collection And Inactivation Of Escherichia Coli, Katrina A. Rieger, Michael Porter, Jessica Schiffman

Chemical Engineering Faculty Publication Series

Quantifying the effect that nanofiber mat chemistry and hydrophilicity have on microorganism collection and inactivation is critical in biomedical applications. In this study, the collection and inactivation of Escherichia coli K12 was examined using cellulose nanofiber mats that were surface-functionalized using three polyelectrolytes: poly (acrylic acid) (PAA), chitosan (CS), and polydiallyldimethylammonium chloride (pDADMAC). The polyelectrolyte functionalized nanofiber mats retained the cylindrical morphology and average fiber diameter (~0.84 µm) of the underlying cellulose nanofibers. X-ray photoelectron spectroscopy (XPS) and contact angle measurements confirmed the presence of polycations or polyanions on the surface of the nanofiber mats. Both the control cellulose and …

Polyelectrolyte-Functionalized Nanofiber Mats Control The Collection And Inactivation Of Escherichia Coli, Katrina A. Rieger, Michael Porter, Jessica D. Schiffman

Chemical Engineering Faculty Publication Series

Quantifying the effect that nanofiber mat chemistry and hydrophilicity have on microorganism collection and inactivation is critical in biomedical applications. In this study, the collection and inactivation of Escherichia coli K12 was examined using cellulose nanofiber mats that were surface-functionalized using three polyelectrolytes: poly (acrylic acid) (PAA), chitosan (CS), and polydiallyldimethylammonium chloride (pDADMAC). The polyelectrolyte functionalized nanofiber mats retained the cylindrical morphology and average fiber diameter (~0.84 µm) of the underlying cellulose nanofibers. X-ray photoelectron spectroscopy (XPS) and contact angle measurements confirmed the presence of polycations or polyanions on the surface of the nanofiber mats. Both the control cellulose and …

Enzyme Activities Of Aerobic Lignocellulolytic Bacteria Isolated From Wet Tropical Forest Soils, Hannah L. Woo, Terry C. Hazen, Blake A. Simmons, Kristen Deangelis

Microbiology Department Faculty Publication Series

Lignocellulolytic bacteria have promised to be a fruitful source of new enzymes for next-generation lignocellulosic biofuel production. Puerto Rican tropical forest soils were targeted because the resident microbes decompose biomass quickly and to near-completion. Isolates were initially screened based on growth on cellulose or lignin in minimal media. 75 Isolates were further tested for the following lignocellulolytic enzyme activities: phenol oxidase, peroxidase, β-d-glucosidase, cellobiohydrolase, β-xylopyranosidase, chitinase, CMCase, and xylanase. Cellulose-derived isolates possessed elevated β-d-glucosidase, CMCase, and cellobiohydrolase activity but depressed phenol oxidase and peroxidase activity, while the contrary was true of lignin isolates, suggesting that these bacteria are specialized to …

Measuring And Predicting Reaction Kinetics For Clean Use Of Biofuels, Phillip R. Westmoreland, Nicole J. Labbe, Wenjun Li, Andrey Pereverzev

Conference on Cellulosic Biofuels

Fuels from renewable biomass already make up part of our energy picture, and that must surely increase. However, relative to petroleum-based fuels, they are thought to generate increased aldehyde and NOx pollutants due to their high content of oxygen and sometimes nitrogen. We are working to explore, explain, and help solve these challenges.

Our two major directions are measuring kinetics with flame molecular-beam mass spectrometry (MBMS) and predicting kinetics using theory, computational quantum chemistry, and our new Reactive Molecular Dynamics methods. We recently built a pioneering MBMS apparatus based on synchrotron VUV-photoionization [Taatjes et al., Science, 308, 1887 (2005)] and …