Abstract

Ion-selective electrodes are sensors that are designed to detect ions selectively and produce a response that can be measured with minimum electronic requirements. The most essential part of the ion-selective electrode is the sensing membrane which is created by integrating an ionophore, the compound that selectively binds the ion of interest, an ion-exchanger, a compound which is necessary to maintain electroneutrality in the membrane, and a polymer/plasticizer matrix, which allows for the rigidity/flexibility of the membrane, respectively. These sensors are then connected to a potentiometer, along with a reference electrode, and the electromotive force (EMF) is the measured output used to determine the ion concentration according to the Nernst Equation. The ultimate goal of our sensors is to able to perform sodium analysis at the patient’s home with a sample of blood straight from the patient’s finger. Sodium is one of the necessary ions found within blood, and when sodium levels are abnormal in the body, hypo- or hypernatremia arises resulting in further complications for the individual. Oftentimes patients must travel to clinics or hospitals to monitor ionic levels in their body, and these sensors will greatly improve the process by which these levels are monitored. The ideal sodium concentration in blood ranges from 136mM/L to 145mM/L, and our sensors have a linear response range of molar to micromolar concentrations, covering the range of sodium in blood[1]. By obtaining a Nernstian response to these ions (59.2 mV/decade), the ion concentration may then be calculated and integrated into a handheld device that will display a digital representation of their sodium levels. By creating these sensors, we will increase the breadth of point-of-care monitoring by patients at their homes while at the same time increasing their quality of life.[1] Adrogue HJ, Madias NE. Hypernatremia. N Engl J Med. 2000 May 18. 342(20):1493-9.

Date Created

March 2020

https://works.bepress.com/cody-autrey/3/download/

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