Mathematical model for a point-of-care sensor for measuring carbon dioxide in blood

详细信息    查看全文

• 作者：Xu Liang Li^aAuthor Vitae ; Hadiseh Karimi^aAuthor Vitae ; P. James McLellan^aAuthor Vitae ; Kim B. McAuley^a ; ^{mcauleyk@queensu.ca" class="auth_mail" title="E-mail the corresponding author}Author Vitae ; Craig Jeffrey^bAuthor Vitae
• 关键词：Point-of-Care device ; pCO2 sensor ; Severinghaus sensor ; Mathematical model ; Blood ; Carbon dioxide
• 刊名：Sensors & Actuators: B. Chemical
• 出版年：2016
• 出版时间：29 November 2016
• 年：2016
• 卷：236
• 期：Complete
• 页码：635-645
• 全文大小：1029 K

文摘

A point-of-Care (POC) pCO₂ device is a small electrochemical sensor for determining the partial pressure of dissolved carbon dioxide in blood samples from patients. A mathematical model is developed to predict the voltage response in a pCO₂ sensor when it is subjected to different CO₂ concentrations in a calibration fluid and in blood samples or control fluids. The model consists of partial differential equation (PDE) material balances for species in the membrane and electrolyte and an algebraic equation relating surface concentrations to voltage. The model considers diffusion of species due to concentration gradients in vertical and radial directions and also reactions in the electrolyte and at the Au electrode. Influential model parameters are identified using estimability analysis and two parameters are fitted using industrial data. The model provides reliable predictions of the dynamic sensor voltage response. Sensor design parameters are varied to study the influence of the electrolyte concentration and sensor geometry on the voltage response, revealing that the most influential parameters are the amount of water in the electrolyte during the sensor operation and the buffer concentration in the electrolyte formulation.