QIAzol Lysis Reagent

Organic extraction of tissues with QIAzol effectively removes genomic DNA and improves the efficiency of extracted RNA in downstream applications. QIAzol is optimized for lysis of fatty tissues, allowing recovery of high-quality RNA from adipose tissue, especially when used in combination with RNeasy silica membrane technology (see figure "High-quality RNA").

Phenol/guanidine-based QIAzol Lysis Reagent can be used to lyse all classes of tissues but is optimized for lysis of fatty tissues, such as brain and adipose tissues. The combination of organic extraction and chaotropic disruption contributes to efficient lysis and higher yields of total RNA. The organic extraction step removes both proteins and DNA, improving the efficiency of further purification steps, for example, precipitation or spin columns. QIAGEN provides several solutions for efficient RNA purification, which integrate QIAzol lysis and RNeasy silica membrane purification technologies in single, streamlined protocols (e.g., RNeasy Plus Universal Kits for any type of tissue).

The standard QIAzol protocol provides an easy-to-follow procedure, combining QIAzol lysis with standard homogenization methods and isopropanol precipitation. Tissue samples are homogenized in QIAzol Lysis Reagent. After addition of chloroform, the homogenate is separated into aqueous and organic phases by centrifugation. RNA partitions to the upper, aqueous phase while DNA partitions to the interphase and proteins to the lower, organic phase. RNA is precipitated from the aqueous phase by addition of isopropanol. The pellet is then washed with ethanol and redissolved in RNase-free water. For high performance in downstream applications, subsequent purification of the RNA is recommended using the RNeasy MinElute Cleanup Kit to remove any contaminating phenol and to concentrate the RNA.

Phenol/guanidine-based QIAzol Lysis Reagent is suitable for all tissues and is optimized for lysis of fatty tissues, such as brain and adipose tissues. We recommend purification of the RNA product with an RNeasy Plus Universal Kit, or the RNeasy MinElute Cleanup Kit, for high performance in any downstream application.