According to the following paper Trizol performs comparable to column purification kits and is a method allowing to isolate RNA and miRNA from the same sample (if this is the limiting factor).

MicroRNA isolation and stability in stored RNA samples. Biochem Biophys Res Commun. 2009: http://www.sciencedirect.com/science/article/pii/S0006291X09018634

Best.

Hey Ryan,

if you avoid columns and use 80%EtOH to wash your RNA sample, Trizol works perfectly well for miRNA isolation.

Best

Franziska

i realy do not suggest to use a standard Trizol extraction protocol to isolate microRNA. Many kits you can use from MARKET. it can make a short time and good results. good luck

I agree with AM, you should really opt for a specialized kit, such as miRVana. A study has been published saying that Trizol favors some miRNAs and fails to isolate those low in G and Cor those with few secondary folding structures. You might introduce a bias into your sample.

http://www.sciencedirect.com/science/article/pii/S1097276512004819

http://retractionwatch.com/2012/07/13/group-retracts-microrna-paper-after-realizing-reagent-was-skewing-results/

Hi Ryan, The trizol extraction protocol, as rightly communicated by some of the responses, is best used for total RNA extraction from tissues and cells.

I have been successful in isolating miRNA from total RNA using kits purchased from Illumina TruSeq. It involves using oligonucleotide adapters, which will ligate to every small RNA present in your total RNA sample and constructing libraries. 

I have attached a link to the protocol from illumina.

All the best.

http://support.illumina.com/content/dam/illumina-support/documents/documentation/chemistry_documentation/samplepreps_truseq/truseqsmallrna/truseq-small-rna-library-prep-guide-15004197-g.pdf

A kit offered via Qiagen can extract both RNAs, the long and the small. 

According to the following paper Trizol performs comparable to column purification kits and is a method allowing to isolate RNA and miRNA from the same sample (if this is the limiting factor).

MicroRNA isolation and stability in stored RNA samples. Biochem Biophys Res Commun. 2009: http://www.sciencedirect.com/science/article/pii/S0006291X09018634

Best.

We do total RNA extractions with trizol looking specifically for mirna levels. The samples you have will work fine.