Isolation of intact RNA is essential for many techniques used in gene expression analysis (eg. RT-PCR). The RNA extraction kit is a ready-to-use reagent for total RNA extraction from tissues. The RNA extraction kit outperforms standard RNA extraction reagents for RNA extraction from fresh or frozen tissues when used in combination with RNA extraction beads (included in RNA extraction kit) and Bioruptor® Plus sonication. Efficient disruption and homogenization of the starting material is an absolute requirement for all total RNA purification procedures. Disruption and homogenization of tissue samples can be carried out rapidly and efficiently using the Bioruptor® Plus.