Hi, maybe RNAlater is a good choice: http://de-de.invitrogen.com/site/de/de/home/brands/Product-Brand/rnalater.html

Cheers, Nadine

I agree. I always use RNAlater.

Thanks both for your answer. Personally my experience with RNAlater is not a very good one when working with fungal material. Fungal cells are very tough and you need mechanical force to break them. Somehow, RNAlater interferes with this decreasing the yield. My samples are extremely small so I need my RNA extraction to be as efficient as it can be.

Then try ethanol (96% not 70%). I worked with tiny insects and storage in 96% ethanol was better than 70%. All the best, Nadine

Thanks Nadine

we use dry shippers for that purpose. They hold -140C for about 21 days and can go on airplanes. They are expensive to get but once you have them they pay off

http://www.cryoport.com/solutions/dry-vapor-shippers/

RNAlater is probably the good choice for solid samples thicker than 5 mm, otherwise we have to cut them. The storage temperature is very important. You can choose -70°C (or dry ice) removing the RNALater after the first incubation or -20°C in the RNA later. The second method is the best to wait at the border, even at room temperature. However, this method prohibits temperature lower than -20°C otherwise you lose the RNA during the defrost of the sample.

For cell samples, RNAlater leads to an important loss of RNA during centrifugation due to the viscosity of RNA Later. In my hands, I have the best results whith guanidine thiocyanate (QiagenRLT buffer, ......) and dry ice for the transport.

I agree with the guys that suggested RNAlater. I am working on placenta biopsies for RNA preservation. I am looking at nutritional availability and transport from mother (supplemented with micro-nutrients before conception) to fetus using immunohistochemical analysis. The RNAlater use has been providing us with good RNA yield. Its optimal performance is dependent on the quantity of tissue to be preserved. I chop them into a 3mm diameter and 2mm height. We use a 2ml sarstedt tubes and add 6 of the small tissues in 1ml RNAlater and we do this as fast as possible as RNA is not stable outside a living body. I hope this helps

Qiagen RNAprotect reagent

http://www.qiagen.com/products/rnastabilizationpurification/rnalaterrnaprotectsystems/rnaprotectbacteria.aspx

RNAlater is very good choice for transport or for long storage you can keep RNA pellet itself in - 80oC or your field sample is tissue, then it is better to store them as such in -80oC till you process for RNA

RNA later worked really well for me

It would also depend on the process that you will later use to isolate the RNA from the tissues but my choice for storage of tissues, prior to extraction or after homogenisation, would be TRIzol (or analogous Guanidinium thiocyanate-phenol-chloroform TRI reagent) to ensure the stability of the RNA.

See "Cancer Epidemiol Biomarkers Prev. 2010 Oct;19(10):2445-52

Effect of long-term storage in TRIzol on microarray-based gene expression profiling".

RNAlater was also recommended to us by our microarray core.

I agree with Anthony, we also store our samples at -80°C in TRizol or Qiazol.

Qiagen RNAlater RNA Stabilization Reagent works really well.

I would also grind the tissue and keep in in Trizol or similar at -80ºC. If you need to ship them, then is not a good idea to send them in Trizol since is so dangerous. I have done that in the past, and what we decided was to perform the full RNA extraction in our lab and send the final RNA sample in dry ice.

RNAlater is fine, but as your samples are already frozen there might be a problem. the qiagen manual says:

"Only fresh, unfrozen tissues can be stabilized using RNAlater RNA Stabilization

Reagent. Previously frozen tissues thaw too slowly in the reagent, preventing the

reagent from diffusing into the tissues quickly enough to prevent RNA degradation."

you could use trizol (add the trizol to the samples on dry ice without letting them thaw, then grind them thoroughly). but as claudio mentioned, you might have problems shipping that.

but i think this is the solution for you:

http://products.invitrogen.com/ivgn/product/AM7030

"RNAlater®-ICE transitions frozen tissue to a consistency that is compatible with

homogenization [...] Soaking frozen tissue samples overnight in RNAlater®-ICE at –20°C [...] changes the physical state of the tissue from brittle to pliable at –20°C, minimizing RNA degradation."

RNA later is a good choice

in TRIzol, if that is the extraction method you will use later