Hi,

I found the following information in the patent information for RNAlater. It seems to give the composition/recipe fir it, and I'm wondering if anyone's tried following it and making their own RNAlater??

QUOTE
COMPOSITION:
In general, the term "RNAlater.TM." is employed to denote the formulation disclosed in Example 2, which is composed of 25 mM Sodium Citrate, 10 mM EDTA, 70 g ammonium sulfate/100 ml solution, pH 5.2.

RECIPE:
Preparation of an Exemplars RNAlater.TM. RNA Preservation Medium

The description in this example provides one manner in which RNAlater.TM. can be prepared. First, one should prepare or obtain the following stock solutions and reagents: 0.5 M EDTA disodium, dihydrate (18.61 g/100 ml, pH to 8.0 with NaOH while stirring); 1M Sodium Citrate trisodium salt, dihydrate (29.4 g/100 ml, stir to dissolve); Ammonium Sulfate, powdered; Sterile water.

In a beaker, combine 40 ml 0.5 M EDTA, 25 ml 1M Sodium Citrate, 700 gm Ammonium Sulfate and 935 ml of sterile distilled water, stir on a hot plate stirrer on low heat until the Ammonium Sulfate is completely dissolved. Allow to cool, adjust the pH of the solution to pH5.2 using 1M H2SO4. Transfer to a screw top bottle and store either at room temperature or refrigerated.
END QUOTE

Information taken from patent information: US Patent 6,204,375

Link:
http://patft.uspto.gov/netacgi/nph-Parser?...5&RS=PN/6204375

Or, go to:
http://patft.uspto.gov/netahtml/search-bool.html
and type 6204375 in the field 1 box, then select “patent number” from drop-down menu & search.
Thanks

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Hi,

That is cool!! Now I know why I hated RNAlater!!!! All those salts... I have said before, but for most protocols you are in an environment where you are able to lyse the cells immediately, and i think you should go straight to GITC/Trizol/TriReagent... I tried RNAlater, but my cells seemed to lyse in it and then it was impossible to get good RNA preps... besides, you can store cells lysed in tri-Reagent at -80C for a long time, and It is just as quick and easy as resuspending them in RNAlater...

I am glad to have seen that You know, if the company would tell you what is going on it would be easier to troubleshoot... oh well, so much for "proprietary"

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Thanks for the info nmkr - very interesting

The following to patents are also worth looking at

http://patft.uspto.gov/netacgi/nph-Parser?...S=REF/6,204,375

http://patft.uspto.gov/netacgi/nph-Parser?...S=REF/6,204,375

http://patft.uspto.gov/netacgi/nph-Parser?...S=REF/6,204,375

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Very very interesting find!

So now comes this question... does "proprietary" actually mean anything if you have to include the components in a patent claim?

-Hank

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It does, in that although anyone can make their own solutions following info in patents, you are not allowed to sell products that are subject to the patent. Therefore you can make your own RNAlater as long as it is for research use only and you do not try and sell it or pass it on to any customer or client

Patents are like chess. You need to block your competitors from copying your innovation

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My experience from using homemade Taq in PCR, is that when you publish, you will get a letter claiming that you have violated the patent by using the technology without a license. Noone ever cared however, and I have not heard about any scientist actually beeing sued - so go ahead, make your own mixes, - it saves a lot of shipment (good for environment, at least).

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