EC2.4 - Effective Sensing Devices for Online Monitoring of Urea and Creatinine in Human Urine

Abstract

In this work, effective and low cost analytical devices were constructed using the concepts of contactless conductivity detector and colorimetric detector. Then, the developed devices were integrated with an automatic flow injection analysis (FIA) for online monitoring of urea and creatinine in human urine samples. The simultaneous determination was operated by injection of urine sample into a carrier stream and flow through a urease column. Urea was hydrolyzed by urease to produce NH3. Using a gas diffusion unit, the generated NH3 in a carrier stream was separated and trapped into an acceptor stream of deionized water as NH4 + form. Changing of conductivity related to the concentration of urea in sample was detected with the in-house contacless conductivity detector. The same sample zone of urine in the donor stream was then subsequently flowed to mix with alkaline picrate for creatinine determination. The colored change of solution after reaction was determined by the in-house colorimetric detector. The proposed system was successfully applied to analysis of urea and creatinine in urine samples. It was found that the method developed here can give similar results compared to those obtained from the reference methods.