How long will my pH buffer last once I open it?

The length of time varies depending on which pH buffers you have open.

pH buffers that have a pH of 4 or 7 can last between 4-8 weeks once they are open while a more basic buffer will only last 1-2 weeks.

The lifespan of your buffers can be shortened by:

• Buffer contamination (your pH electrode should not be inserted into a bottle of buffer).
• Leaving the bottle uncapped.
• Storing the buffers in a place that is too hot or too cold.
• Leaving your buffers in direct sunlight.