Qiagen, 768536, QIAsymphony PAXgene Blood ccfDNA Kit (192)

The PAXgene Blood ccfDNA System consists of a blood collection tube (PAXgene Blood ccfDNA Tube) and a ccfDNA purification kit for the QIAsymphony (QIAsymphony PAXgene Blood ccfDNA Kit).
The fully automated QIAsymphony PAXgene Blood ccfDNA Kit procedure generates ccfDNA yields comparable to the manual QIAamp Circulating Nucleic Acid Kit procedure (see figure High performance, comparable to QIAamp Circulating Nucleic Acid Kit). Since yield is strongly dependent of donor, individual yields may vary. Onboard measures of the QIAsymphony SP minimize cross-contamination.
Apoptosis and lysis of white blood cells in unstabilized whole blood releases genomic DNA into plasma, which dilutes naturally occurring ccfDNA. PAXgene Blood ccfDNA Tubes contain an additive that prevents blood coagulation and immediately stabilizes blood cells via a non-crosslinking stabilization solution (see figure PCR results from blood collected in PAXgene Blood ccfDNA Tubes remain stable over storage time). This impedes the release of intracellular DNA and maintains constant ccfDNA levels in plasma. When used with PAXgene Blood ccfDNA Tubes, the proven magnetic particle technology of the QIAsymphony PAXgene Blood ccfDNA Kit provides a rapid, automated procedure to isolate ccfDNA of high quality and purity (see figure Isolated ccfDNA is compatible with methylation-specific downstream applications).
The workflow begins with a centrifugation step that separates plasma from the cellular fraction of the whole blood collected into PAXgene Blood ccfDNA Tubes. The plasma is then carefully transferred into a second tube. A second centrifugation step can be carried out optionally to remove any traces of buffy coat. The pure plasma is then transferred to a third tube which is loaded into the QIAsymphony SP. In the QIAsymphony SP, plasma proteins are digested by proteinase K while ccfDNA binds to the surface of magnetic beads (see figure The QIAsymphony SP processes samples containing magnetic particles). Depending on the chosen protocol line, predominantly small ccfDNA fragments (STA protocol line) or small and large ccfDNA fragments (LAF protocol line) are isolated. Three wash steps ensure contaminant removal. Finally, ccfDNA is eluted from the magnetic particles and is ready for use in downstream applications (see figure Two protocol lines of the QIAsymphony PAXgene Blood ccfDNA Kit for different research needs).