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Office: MEYR 240
Phone: 410-455-2969
Professional Interests
Sarah Wassink
Graduate Student
B.A. College of Notre Dame of Maryland 2006
The new pump I am using

Analytical Chemistry, Environmental Science, Mathematics, Education

Most recent abstract:

In vivo microdialysis has been popularized as a tool for monitoring extracellular space of living tissue, and, therefore, is widely used in the pharmaceutical industry for pharmokinetic studies. Likewise, in vitro microdialysis can be used for continuous monitoring of large-scale bioprocesses, such as enzymatic treatment of foods or production of biofuels. Both methods take advantage of selective diffusion of small molecules out of the bioreactor by passing a perfusate fluid through the inside of a low-volume, tubular membrane. The dialysate can be assayed to develop a dynamic concentration versus time profile of the system under study. One advantage of using very slow flow rates is that more time is permitted for the extraction process to reach equilibrium, and in turn allows for better recoveries. 
Presently, syringe-pumps are used to deliver perfusate, but for large-scale processes these devices can be laborious because they not only require reloading for long-term applications, but are also prone to reproducibility problems. We are investigating the advantages of using a stepper motor driven and computer controllable pump with bidirectional pulseless flow. The pump specializes in precision fluid control with nano- and micro-range control of the flow rate and volume delivery, making it a superior companion to microdialysis. Precision control of the perfusate will ensure that the advantages of using this computer programmable pump are long-term, enabling better in vitro microdialysis analysis by not only improving analyte recoveries with slower flow rates but also improving reproducibility with electronic control.