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difference between distilled water and deionized water - (Oct/16/2005 )

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Anyone could enlighten me on the difference between distilled water and deionized water? When do we use distilled water,and when do we use deionized water?thanks

-natural_leaves-

They are the same thing. Both are just water with ions removed. Distilled water has been deionised by distillation as apposed to another technique such as ion exchange chromotography. The end product is the same and either can be used. Most labs will not have distilled water anyway even if some people still call it distilled rather than deionised.

-ajames-

and what about double-distilled H20?
what is the difference between all these 3 methods to remove ions?

Seb_

-tryptofan-

QUOTE (tryptofan @ Oct 17 2005, 11:38 AM)
and what about double-distilled H20?
what is the difference between all these 3 methods to remove ions?

Seb_

I would say that there is a difference between distilled water and deionized water. Especially double distilled water is quit pure but a little bit old fashioned. these days most people use MilliQ water (which is deionised water that has passed a special millipore filter).

Deionised water is water that has passed only an (an)ion-exchange colomn. So in our lab we use both deionised water and milliQ water. Deionised water is only used for cleaning, washing and diluting things like electrophoresis buffer. More important solutions are always made in MilliQ. Also solutions for tissue culture should always be made from milliQ.

-Theo22-

QUOTE (tryptofan @ Oct 17 2005, 01:38 AM)
and what about double-distilled H20?
what is the difference between all these 3 methods to remove ions?

Seb_

Double distilled just means distilled twice so even more of the ions are removed. I don't know if anyone would actually use double distilled anymore since milli Q is available. Milli Q is double deionised water-deionised water passed through a second ion exchanger. All of these techniques do the same thing-remove ions. Some distillation columes will be more effective than others and some ion exchange columes will be more effective than others. The safest thing to do is just always use the best quality water you have access to.

-ajames-

Can you elucidate more on this? THANKS!

QUOTE (Theo22 @ Oct 17 2005, 06:14 AM)
I would say that there is a difference between distilled water and deionized water. Especially double distilled water is quit pure but a little bit old fashioned.

-MaximinaNYC-

"old-fashinoned"??

Recently, when our milliQ went kaput I replaced it with ddH20. Things worked fine...

Another question related to this thread is...
I have seen some people writing on their carboyles "Do not fill water over ___ Osmoles"
What does this mean??

-Pria-

So it really doesnt matter if i use distilled water to dilute my solution instead of using deionized water?I thought somehow deionized water is more "advance" and "cleaner" than distilled water.Based on your explainations, deionized water has no difference with distilled water?What does ddH20 stand for?

-natural_leaves-

sorry biggrin.gif
ddH20 stands for double distilled H20. I made up all my electrophoresis buffers in ddH20 and it was fine. ..Although i stuck to making sterile trypsin and all the other cell culture stuff with the deionized water...after passing it thru a millipore filter..

-Pria-

I think it's just a matter of schematics here -- distilled (or double distilled) water is deionized water -- water that has been deionized by distillation. The generic term "deionized water" just doesn't specify the method by which ions were removed.

It's like saying all lacerations are wounds, but not all wounds are lacerations...

-HomeBrew-

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