The objective of this project is to demonstrate the feasibility of a membrane-sensor system suitable for use in a miniature fiberoptic potassium-ion sensor (optrode) for continuous monitoring in body fluids.Potassium levels are commonly monitored during cardiac surgery, diabetic acidosis, renal failures, and other acute conditions. Potassium levels can be very labile, and thus monitoring requires frequent measurements, with substantial labor and lab charges. A relatively inexpensive, disposable, and continuous probe would give immediate clinical information and would be cost effective.The specific aims of the Phase I project are to: (1) synthesize a dye molecule that is sensitive to the concentration of potassium-ion in the pathophysiological range; (2) develop a means of immobilizing the K+ sensor dye molecule within a semipermeable membrane; (3) construct a working model of the fiberoptic probe; and (4) determine the effectiveness of the probe by in vitro analysis of body fluid with known K+ concentrations.The longer-term Phase 11 objectives are to miniaturize the K+ probe and combine it into a multiparameter probe for monitoring several components, such as 02, C02, and pH.National Heart, Lung, And Blood Institute
