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Storage buffer for electrode - pH 7.0 standard buffer in stead of storage buffer? (Jun/15/2009 )

II would like to know if itís correct to use pH 7.0 standard buffer in stead of storage buffer for the pHmeter electrode.
I think I read somewhere that itís not correct, but Iím not sure and I couldnít find it again.
Here in many labs 7.0 buffer is used.

Could you tell if itís ok or not and why?

Thanks!

-aztecan princess-

We store our electrode in 1M KOH...
But I have no idea if this is the best way.

-mastermi-

depending on the electrode, the proper storage solution is kcl (with or without agcl, basically, the electrode fill solution). the concentration will be given in the paperwork that comes with the electrode.

do not store in pH 7 standard buffer. it is phosphate and, over a long period of time, will attack the glass.

in a pinch, you can store in pH 4 standard buffer (phthalate).

-mdfenko-

mdfenko on Jun 15 2009, 01:45 PM said:

depending on the electrode, the proper storage solution is kcl (with or without agcl, basically, the electrode fill solution). the concentration will be given in the paperwork that comes with the electrode.

do not store in pH 7 standard buffer. it is phosphate and, over a long period of time, will attack the glass.

in a pinch, you can store in pH 4 standard buffer (phthalate).


thank you very much.

In this case, mm, I think I'll prepare KCl 3.5 M and use it (I don't have AgCl).

chear!! ;)

-aztecan princess-