Instruments measuring pH offer fast and simple operation, but accuracy, reliability and repeatability of results are subject to various sources of error like contamination, asymmetric measurement cell, membrane resistance or ambient temperature.
In this presentation an overall model of factors that have an impact on pH measurement is presented. Then we reduce the complexity of the model to a more practical model of the measurement itself.
Step by step, each influencing factor of the practical model is explained. On every factor the mechanism that leads to this error is explained, as far as known to science and our current research at METTLER TOLEDO. From our day by day research and work with pH measurements, we acquired a fair amount of experience values that we'll share with you in this presentation. Last but not least, methods to counter or reduce those errors are explained.
With the knowledge provided in this presentation and the rule of tackling major impacting factors first, you have taken the first step to make your pH measurement more precise and more reliable.
- Learn how to reach an accuracy of ±0.05 pH using good laboratory practices
- Understand how the accuracy can increase to up to ±1.6 pH rendering the measurement useless
- Discover how to tackle the biggest influencing factors during measurement and calibration to effectively reduce the error
Patrick Kurth holds a Diploma degree in analytical chemistry and a master's degree in business innovation from University of St. Gallen. He has more than 10 years of work experience in pharmaceutical industry, chemical engineering and analytical instruments business.
Since three years he works as international product manager for the electrochemical meters business at METTLER TOLEDO and is a subject matter expert on pH measurements, pH meter development and standards thereof.