RNeasy Plus Universal Kits

The RNeasy Plus Universal procedure allows high, reproducible RNA yields from any type of tissue, including fatty tissues and difficult-to-lyse tissue (see table). Yields can vary due to factors such as species and developmental stage, especially with adipose tissues.

The RNeasy Plus Universal procedure enables purification of RNA from any type of tissue, including fatty or difficult-to-lyse tissues. RNeasy Plus Universal Kits integrate phenol/guanidine-based sample lysis and silica-membrane purification of total RNA. QIAzol Lysis Reagent, included in the kits, is a monophasic solution of phenol and guanidine thiocyanate, designed to facilitate lysis of all kinds of tissues and to inhibit RNases. The highly efficient lysis and the subsequent removal of contaminants by organic phase extraction enable the use of larger amounts of tissue with RNeasy spin columns. gDNA Eliminator solution effectively removes genomic DNA contamination and significantly improves separation of DNA into the interphase.

The RNeasy Plus Universal procedure is easy to follow and, compared to phenol/chloroform treatment with a subsequent cleanup procedure, much faster and more efficient with better RNA purity and yield (see flowchart "RNeasy Plus Universal Mini and Midi procedures"). Total RNA is purified from up to 50 mg tissue using the RNeasy Plus Universal Mini Kit or up to 250 mg tissue using the RNeasy Plus Midi Kit.

Tissue samples are homogenized in QIAzol Lysis Reagent using the TissueRuptor, TissueLyser LT, or TissueLyser II. After addition of gDNA Eliminator Solution and chloroform, the homogenate is separated into aqueous and organic phases by centrifugation. The upper, aqueous phase with RNA is collected, mixed with ethanol, and RNA is purified using RNeasy spin columns. Total RNA binds to the spin column membrane, and phenol and other contaminants are efficiently washed away. High-quality RNA is eluted in RNase-free water.

The procedure provides an enrichment for mRNA since most RNAs <200 nucleotides (such as rRNAs and tRNAs) are excluded. The RNeasy Plus Universal procedure can be modified to allow the purification of total RNA containing small RNAs, such as miRNA, from cultured cells. 

RNA purified using the RNeasy Plus Universal Kits is ideally suited for downstream applications that are sensitive to low amounts of DNA contamination, such as quantitative real-time RT-PCR. The purified RNA can also be used in other applications.