RNA Isolation: Does Trizol Reagent contain water? If not, where does water in the 'aqueous phase' come from?

Question

Madeline Andrews · Accepted Answer

My guess: TRIzol® contains water.

TRIzol® is a "monophasic" solution of phenol, guanidine isothiothiocyanate, and other proprietary components.

Nowhere in the company literature, patents, or MSDS sheets are the words "water" or "aqueous" found.

Yet, the reagent is buffered, so there is probably an aqueous component.

Furthermore, recipes for homemade "TRI" use components such as pH 7.0 buffer, water-saturated phenol, and aqueous solutions of guanidinium thiocyanate, sodium citrate, laurylsarcosine, and mercaptoethanol.

As you say, where does the water in the aqueous phase come from, if not from the reagent?

Connor Abernathy · Answer

undefined Trizol Reagent breaks down cells and tissues, releasing the contents of the cells, including RNA, into the aqueous phase. This phase then separates from the organic phase, which contains RNA, DNA, and proteins, with the addition of chloroform and centrifugation. Trizol Reagent does not contain water; the water in the 'aqueous phase' during RNA isolation comes from the sample itself.