The PAXgene Blood miRNA System consists of the PAXgene Blood miRNA Kit for purification of total RNA, including RNA longer than approximately 18 nucleotides, and PAXgene Blood RNA Tubes (available from BD, cat. no. 762165) for collection, stabilization, and transport of blood. Purification is carried out using silica-based RNA purification technology in a spin-column format. Purification can be carried out manually, using a microcentrifuge, or automated on the QIAcube. Used with the tubes, the kit provides a complete preanalytical solution for collection and stabilization through to purification of high-quality total RNA, including miRNA, for molecular analysis.