This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision Next revision Both sides next revision | ||
ph_measurement_tips [25/06/2019 06:17] pieter |
ph_measurement_tips [27/06/2019 13:08] pieter |
||
---|---|---|---|
Line 10: | Line 10: | ||
//**What pH electrode do I use for a specific application? | //**What pH electrode do I use for a specific application? | ||
Follow the general rules below for selecting the right pH electrode: | Follow the general rules below for selecting the right pH electrode: | ||
- | * Check the [[http:// | + | |
* Glass bodied pH electrodes may be used in most sample types. | * Glass bodied pH electrodes may be used in most sample types. | ||
* Epoxy bodied pH electrodes are designed for rugged environments, | * Epoxy bodied pH electrodes are designed for rugged environments, | ||
* For situations containing proteins, sulphide, and TRIS, use double junction electrodes. | * For situations containing proteins, sulphide, and TRIS, use double junction electrodes. | ||
* For viscous or dirty samples, use sleeve junction electrodes for best results and easy cleaning. | * For viscous or dirty samples, use sleeve junction electrodes for best results and easy cleaning. | ||
- | \\ | + | * Check the [[http:// |
//**What filling solution do I use?**//\\ | //**What filling solution do I use?**//\\ | ||
The recommended filling solution depends on the type of electrode. Some electrodes have sealed references and do not require filling solution. For refillable pH electrodes, use a 3...4 M KCl solution.\\ | The recommended filling solution depends on the type of electrode. Some electrodes have sealed references and do not require filling solution. For refillable pH electrodes, use a 3...4 M KCl solution.\\ | ||
Line 51: | Line 51: | ||
* If the electrode is new (or has been dry) and drifting, the electrode may not be properly conditioned. Refer to the appropriate electrode instruction manual for details. | * If the electrode is new (or has been dry) and drifting, the electrode may not be properly conditioned. Refer to the appropriate electrode instruction manual for details. | ||
* If the electrode is stable in buffers but not in the sample, the electrode may be incompatible with the sample or application. | * If the electrode is stable in buffers but not in the sample, the electrode may be incompatible with the sample or application. | ||
- | * If the electrode is drifting in buffers and samples, the electrode may require cleaning. | + | * If the electrode is drifting in buffers and samples, the electrode may require cleaning, see [[http:// |
* Electrode that have been stored for longer periods may have an air bubble in the pH sensitive glass bulb. To remove it, take the electrode in the hand with the glass buble pointed downwards and shake it like a clinical mercury thermometer until the bubble has vanished. | * Electrode that have been stored for longer periods may have an air bubble in the pH sensitive glass bulb. To remove it, take the electrode in the hand with the glass buble pointed downwards and shake it like a clinical mercury thermometer until the bubble has vanished. | ||