10x PBS vs 1x PBS

There has been some confusion about when to use 10x PBS and when to use 1x PBS. I believe this confusion stems from a misunderstanding of the "10x" or "1x" concentration notation. The working concentration of a buffer or solution is always 1x.

For instance, a Coke in an aluminum can is at a 1x concentration, while the syrup that goes into the soda machine to make the Coke is at a 10x concentration (or something like that). That means, the syrup has to be diluted 10-fold to get to the regular 1x concentration of Coke.

So - if you're trying to figure out what concentration of PBS to use, spend some time thinking about what concentration you want it to be. If you're reconstituting protein target into 100 uL of buffer. You may suspend it in 100 uL of 1x PBS or you may suspend it in 90 uL water + 10 uL of 10x PBS. Does that make sense?

I hope this helps.
:)
Gwen