Abstract:     It has been recognized for decades that charged colloids and particulate matter will transport in direct current electric fields. However, routine, high efficiency separation and analysis of colloidal or larger particles by electrophoresis has not been as successful as it has for small molecules and macromolecules. Selective, high efficiency separations of intact microbes (e.g., bacteria, viruses, etc.) may, in some cases, allow them to be identified and quantified in much the same way that molecules are done today. Two different capillary electrokinetic approaches can be utilized. The first approach used a dissolved polymer based CE separation that may be affected by the size and shape considerations. Another approach uses capillary isoelectric focusing (CIEF).

Remarkably high apparent efficiencies (10⁶ - 10⁹ theoretical plates per meter) in capillary electrophoresis (CE) can be achieved in the separation of microorganisms. No deliberate stacking is used in these applications. Seemingly, the investigated living organisms behave differently than molecules under an applied electric field. For molecules, these extremely high efficiencies are very unusual, and have not been reported thus far. Using a 488 nm argon-ion laser coupled to a charge-coupled device camera (CCD), it was possible to monitor the migration behavior of stained microorganisms of a length of a 10 cm capillary. In some cases, 60 - 70% of the monitored detection window could be filled with analyte without significant loss in peak efficiency. The effect of pH, polymer concentration, buffer concentration, etc. on the ultra-high efficiency and reproducibility of the separation was investigated.

Biography:     Daniel W. Armstrong is the Caldwell Distinguished Professor of Chemistry at Iowa State University, and a Research Supervisor/Laboratory Director at the Ames National Laboratory. He is a consultant for several chemical and pharmaceutical companies. He has made both films and radio broadcasts for the American Chemical Society and developed and hosted a show ("We're Science") for National Public Radio (NPR) that was syndicated nationally on 160 stations plus the Armed Forces Network and reached a population of over 70,000,000.

He received his B.S. degree (1972) from Washington and Lee University and his M.S. degree (1974, Oceanography) and Ph.D. degree (1977, Bio-organic Chemistry) from Texas A&M University. He has over 300 publications including 20 book chapters, one book ("Use of Ordered Media in Chemical Separations") and eight patents. Several of his research publications have been in the Scientific Citation Index Review as "Highly Cited Papers". He has given approximately 290 invited seminars and colloquia worldwide. He is considered the "Father" of micelle and cyclodextrin-based separations. He elucidated the first chiral recognition mechanism by cyclodextrins. He also first developed macrocyclic antibiotics as chiral selectors. He is one of the world's leading authorities on the theory, mechanism and use of enantioselective molecular interactions. Over 30 different LC and GC columns originally developed in his laboratories have been commercialized and/or copied worldwide. His work and columns were in part responsible for the chromatography and electrophoresis - lead revolution in chiral separations over the last one and one half decades. Currently the columns, chiral selectors and techniques he developed dominate the world of bio-analytical enantiomeric separations. Most recently, he has developed methods for the rapid, high efficiency separation identification and quantitation of intact microbes. According to the Scientific Citation Index, he is one of the more highly cited chemists in the world.

Dan Armstrong has won several teaching and faculty excellence awards as well as the Eastern Analytical Award for Chromatography (1990), Great Britain's Martin Medal (1991) (named for Nobel laureate A.P.J. Martin), and the Isco Award for contributions to instrumentation for biochemical separations(1991), the Presidential Award for Research and Creativity (1993), the ACS Midwest Award in Chemistry (1993), the Perkin Elmer Award for Capillary Electrophoresis (1994), The R&D 100 Award for Inventions leading to a better world (1995), and was named a Fellow of the American Association of Pharmaceutical Scientists (1995). In 1996 he was given the Benedetti-Pichler Award in microchemistry; in 1997, the Karen Morehouse Award, in 1998 the ACS Helen M. Free Award, and in 1999 the ACS Award in Chromatography, in 1999 the Distinguish Scholar Award from Hope College/Park Davis, and in 2001 the Chicago Area Chromatography Discussion Group (CCDG) Merit Award.

Most recently, he was awarded the Weber Medal, and was made an honorary member of the Slovacae Pharmaceutical Society, for his contributions to the Pharmaceutical Sciences (2001). He is the Separations Editor for Analytical Chemistry and was the Editor of the international journal Chirality, a Section Editor for Amino Acids, and a member of the Editorial Board of many other journals. He was on the Instrumentation Advisory Board and Editorial Board of Analytical Chemistry. He is a member of the American Chemical Society, American Association for the Advancement of Science, Smithsonian Associate and Sigma XI. His current research involves chiral recognition, specific separation and detection of enantiomers, cyclodextrin chemistry, investigation of biologically active molecules, macrocyclic antibiotics, and high efficiency microbial analysis, and use of room temperature ionic liquids in chemical analysis and separation.