James Bennett ACF Abstract FY12

"Isotachophoretic Focusing of Bacteria and Fungi for Analysis"

Conference Name: 46th Midwest 39th Great Lakes Joint Regional American Chemical Society (ACS) Meeting

In this experiment we attempt to use the isotachophoresis mode of capillary electrophoresis to focus and potentially separate bacterial and fungal species. Isotachophoresis is typically used in biochemistry to concentrate and separate protein samples based on their electrophoretic mobilities as compared to the other components in a multi-electrolyte system. The same basic principle may be applied to the analysis of whole cells by exploiting their differences in size and surface charges. Different bacteria such as gram positive and gram negative have different surface characteristics as well as being vastly different from that of fungi. By focusing the cells into distinct zones based on these surface characteristics it would be possible to differentiate between species and thus have a fast and inexpensive test to determine the cause of sample contamination. Initial data shows success in focusing individual samples of gram positive (Bacillus subtilis) and gram negative bacteria (Escherichia coli), as well as single cell fungi (Candida albicans) in a two electrolyte system. In this system, the cells themselves act as a third electrolyte component which is highly focused between the leading and terminating electrolytes. Cell focusing typically was accomplished in under 10 minutes of isotachophoresis. Current work focuses on the separation of these model species in a mixed bacterial or fungal sample. This may be accomplished by utilizing an electrolyte system with increasing numbers of components having mobilities that bracket each species in the sample. The speed of this test could potentially allow for faster analysis in many settings such as medical centers, food processing facilities, and water treatment plants.