& Reports on the use of heparin as a chiral additive show widely different separation conditions and inconsistent results. A systematic evaluation of the separation of pheniramine enantiomers using heparin as a chiral selector suggested that heparin was interacting with the capillary surface at acidic pH. Further testing confirmed the interaction between heparin and the capillary surface at acidic pH causing an increase in the electroosmotic flow (EOF). Polyelectrolyte multilayer (PEM) was chosen as a potential means to eliminate the interaction between heparin and the capillary surface. Generation of the PEMs on a bare capillary was monitored by measuring the changes in EOF following the deposition of each polyelectrolyte layer; deposition provided consistent EOF intensities and facilitated control over EOF direction. Results from this study indicated that a stable PEM system could be generated, which prevents the interaction of heparin with the capillary surface. This PEM system showed excellent reproducibility, with only a slight loss of resolution due to the increased interactions between the analyte and the charged capillary wall.

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There is a continuing drive in microfluidics to transfer microchip systems from the more expensive glass microchips to cheaper polymer microchips. Here, we investigate using polyelectrolyte multilayers (PEM) as a coating system for poly (methylmethacrylate) (PMMA) microchips to improve their functionality. The multilayer system was prepared by layer-on-layer depositon of poly (diallydimethylammonium) chloride (PDAD) and polystyrene sulfonate (PSS). Practical aspects of coating PMMA microchips were explored. The multilayer buildup process was monitored using EOF measurements, and the stability of the PEM was investigated. The performance of the PEM-PMMA microchip was compared to those of a standard glass microchip and a PEM-glass microchip in terms of electroosmotic flow and separating two fluorescent dyes. Several key findings in the development of the multilayer coating procedure for PMMA chips are also presented. It was found that, with careful preparation, a PEM-PMMA microchip can be prepared that has properties comparable -and in some cases superior -to those of a standard glass microchip.

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In order to encourage female students to pursue science as a career, an overnight science camp known as the Women in Science Experience (WISE) was developed and implemented at Mount St. Joseph University. The camp was developed for girls who were 14-17 years of age as a residential experience to simulate life on a university campus. This manuscript describes the implementation of the camp, including development of content and organization of the camp schedule. The camp was evaluated by student participants using a survey that contained Likert-style and open response questions, with students reporting overall satisfaction with the camp. The manuscript discusses the student responses to the survey and describes the lessons learned from the entire process of developing and running WISE.