Mechanical Engineering Faculty Research


Novel Sensor for Measuring Sodium Concentration for Dialysis Applications

Document Type

Contribution to Book

Publication Date



One of the critical medical problems facing society today is the growing number of patients diagnosed with End-Stage Renal Disease (ESRD). Patients diagnosed with ESRD often face a problem of limited organ transplantation possibilities and time consuming, cumbersome as well as painstaking treatments that affect patients’ quality of life. This study is part of a larger effort to develop new types of dialysis treatments focused on improving the quality of life of ESRD patients. The focus of this paper is the development of a simple, yet reliable sensor that can measure the toxic ion levels in the human body so that the right type and amount of an ion absorbing material can be released in the body to absorb these ions. The sensor is based on the change in resistivity of the solution with different ion concentrations. It has been shown that that by using customized plates with different combinations of metals, the voltage readings across different terminals is unique to the concentration of the solution. By using various metal electrodes of different sizes and distances, one can develop a table of values for the ion concentration vs. voltage (actually measuring resistance by keeping track of the current). Such a look-up table can then be used to measure the ion concentration in an unknown solution. This concept will then be extended to solutions containing multiple ions. The key to the success of this approach lies in the formation of the sensing plate that has multiple electrodes of different metals, sizes and distances between them, all which contribute to a distinct and unique pattern for the current concentration of ions in the solution. The two most critical ions are sodium and potassium, and this paper presents results for only the sodium trials to show the feasibility of this approach.

Publication Title

25th Southern Biomedical Engineering Conference 2009, 15 – 17 May 2009, Miami, Florida, USA



First Page


Last Page