RNAlater™ Stabilization Solution (Invitrogen™)

RNAlater RNA Stabilization Solution stabilizes and protects cellular RNA in intact, unfrozen tissue samples, eliminating the need to immediately process tissue samples or to freeze samples in liquid nitrogen for later processing. Tissue pieces can be harvested and submerged in RNAlater RNA Stabilization Solution for storage without jeopardizing the quality or quantity of RNA obtained after subsequent RNA isolation. Advantages of using RNAlater RNA Stabilization Solution:

• Effectiveness—stabilize RNA for 1 day at 37°C, 1 week at 25°C, 1 month at 4°C, or indefinitely at -20°C
• Simplicity—a single reagent that immediately inactivates RNases and stabilizes RNA within tissues or cells
• Convenience—no need to freeze samples in liquid nitrogen or rush samples back to the lab freezer
• Mobility—perfect for tissue collection 'in the field'
• Versatility—compatible with many RNA isolation procedures, including most RNA isolation kits

Applications
RNAlater RNA Stabilization Solution has been tested on a variety of mammalian tissues, plants, E. coli, Xenopus, fish, and Drosophila. It is ideal for:
• Protecting RNA integrity in tissues rich in RNases
• Collecting samples from different time points without having to process the samples from each time point immediately
• Archiving tissues for future microdissection
• Submerging animal cavities or organs to stabilize RNA during lengthy dissection procedures
• Collecting samples at locations (e.g., hospitals, field sites, the space shuttle) where immediate RNA isolation is not possible
• Shipping samples on wet ice or even at room temperature if shipped overnight

RNAlater RNA Stabilization Solution procedure
The dissected tissue (less than 0.5 cm in any one dimension) is simply submerged in approximately 5 volumes of RNAlater solution at room temperature. The solution permeates the cells, stabilizing the RNA. The sample can then be stored indefinitely at -20°C (the tissue does not freeze), at 4°C for up to a month, or at 25°C for up to a week. For RNA isolation, the tissue is simply removed from RNAlater solution and treated as though it had just been harvested. Most tissues can be transferred directly to a lysis buffer and homogenized. Samples treated with RNAlater solution and then frozen can be ground with mortar and pestle or thawed and processed like fresh tissue without concern for cell rupture and release of RNases since the RNases have already been inactivated. Cells can be spun out and then added to lysis buffer, or in some cases, RNAlater solution can be added along with the cells directly to the lysis buffer.

Compatible with a variety of procedures
RNAlater RNA Stabilization Solution is compatible with one-step RNA isolation methods, such as TRIzol Reagent; with glass binding methods, such as Qiagen's RNeasy or the Ambion RNAqueous kit; with acid phenol extraction methods, and with methods that use oligo(dT) selection of mRNA, such as the Ambion Poly(A)Purist kit. In-house research, as well recently published independent research, indicates that the use of RNAlater RNA Stabilization Solution for tissue storage does not affect the outcome of subsequent RNA expression analysis experiments compared to other processing methods.