Mettler Toledo, a specialist supplier of quality weighing and measuring solutions have produced a guide to pH measurement
Mettler Toledo believe ensuring accuracy for simple stick measurements such as pH, ion selective (ISE) and conductivity measurements, even in hard to handle or hazardous samples, is just as important as more complex measurements.
Accuracy can be improved by following easy best practice steps, including:
- use fresh buffers: unopened buffers and standards typically have a shelf life of 2 years. Always use fresh buffer and standard solutions, store buffers in closed bottles and never use them after the expiry date.
- understand temperature: use an electrode with a built in temperature sensor. Meters with automatic temperature compensation (ATC) can adjust for temperature for buffers/standards during calibration only; sample measurements cannot be adjusted for.
- electrode cleaning, storage and maintenance: the electrode is the only part of the measuring system that comes into contact with the sample, so it is important to clean, maintain and store the electrode according to manufacturer's instructions to extend lifetime.
For more advice, download the Mettler Toledo pH theory guide, which covers variables to consider, how to prepare samples and troubleshooting tips for electrodes. Visit www.mt.com/uk-ph-guide.
Alternatively email email@example.com to discuss your pH needs with an expert.