The PicoPure RNA Isolation Kit from Arcturus was developed to efficiently isolate total RNA from a small number of cells - using this kit it is possible to recover total RNA from as few as ten cells. This kit is also flexible enough to be used for isolations from samples containing up to 100 ug RNA. The procedure involves passing cell extracts through affinity spin columns, which bind and immobilize the RNA. The bound RNA is then washed and total RNA can be eluted to a final volume of 10 ul. The kit is especially good for RNA recovery from cellular samples isolated by laser microdissection technology. The quality of the recovered total RNA is good enough that it can be directly used in downstream applications such as reverse transcription and amplification by in vitro transcription. The total time necessary to complete the isolation process is less than 1 hour.
Together with collaborators from the clinic, our lab started a project to identify genes responsible for hypertension in the kidney glomerulus. In order to obtain glomeruli samples, it was necessary to use laser microdissection technology to isolate glomeruli tissue away from surrounding kidney tissue. One of the challenges we encountered was that we could only recover extremely small cell numbers from these tissue sections. Since our ultimative goal was to perform genome-wide gene expression analysis using DNA microarrays, the recovered RNA had to be amplified. We tried several protocols and kits for the isolation of RNA from small amounts of tissue, however PicoPure turned out to be the most efficient one. The whole isolation procedure was fast (it takes us less then an hour), which is in our case very advantageous. We usually dissect a lot of samples per experimental session, therefore we require a robust RNA isolation system so that we can be finished in a minimal amount of time. Another feature that we appreciated was the fact that using the PicoPure system, we could elute the RNA in as little as 10ul. Thus we avoided the need for concentrating RNA by vacuum centrifugation. This allowed us to proceed directly to reverse transcription for later RNA amplification. While processing larger samples of cells, we checked the RNA quality several times using an Agilent Bioanalyser, and we consistently obtained high quality total RNA.
Taken together the PicoPure RNA Isolation kit is the product of choice for those who have to deal with extremely small cell numbers. I would especially recommend this product to those researchers who plan to use their RNA preparations for microarray gene expression studies.
Michal Janitz, M.D.
Max Planck Institute for Molecular Genetics
Berlin, Germany