Hi Fenglong

I hope my comment will be helpful for you.

1-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).

2-Deionised water is water that has passed only an (an)ion-exchange colomn. 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.

3-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.

best regards

Randa Osman

Hi Fenglong

I hope my comment will be helpful for you.

1-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).

2-Deionised water is water that has passed only an (an)ion-exchange colomn. 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.

3-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.

best regards

Randa Osman

Assume machines are set up correctly and maintained, the double distilled should be as good a type I water as the MilliQ. Both will yield 18 mOhm water with less than 50 ppm Organics. Both machines should be fed with Type2 RO feed water. Double distilled water is "Old school " and is the original "cell culture water". lol

Double distilled is better for large volume users and is free of pyrogens

MilliQ is more often used as a point of use polisher. Expensive to use for large volumes of water but great for a single lab. If UV present, pyrogens are possible.

Here is the ultimate source of lab water

https://www.orf.od.nih.gov/PoliciesAndGuidelines/Documents/DTR%20White%20Papers/Laboratory%20Water-Its%20Importance%20and%20Application-March-2013_508.pdf

Check this link

http://www.protocol-online.org/biology-forums/posts/10380.html

Greeting

check this link as well

https://www.uswatersystems.com/deionized-water-vs-distilled-water

Dear Mr. Wang

In best of my knowledge MiliQ water is deionized water, Miliq is the brand from Merk milipore system which produce deionized wate. But due to popularity of brand and accuracy of this system people use the name MiliQ.

MiliQ water is deionized water, Miliq is the brand from Merk milipore system which produce deionized wate