QIAamp Circulating Nucleic Acid Kit (50)

This QIAGEN kit is designed for efficient isolation of free-circulating DNA and RNA from human plasma and serum, as well as other cell-free body fluids such as urine. Purification uses selective binding to a silica-based membrane and is carried out manually on a vacuum manifold using QIAamp Mini Columns, in four steps — lyse, bind, wash, and elute. Up to 24 samples can be processed in less than 2 hours, with no phenol–chloroform extraction required, and the workflow can be automated on the QIAcube Connect.

Starting sample volumes of 1–5 ml are supported, with flexible elution volumes between 20 µl and 150 µl for concentration of low-abundance nucleic acids. The kit isolates free-circulating DNA, RNA and miRNA, as well as viral DNA and RNA. RNA can be purified without co-purification of DNA using the RNase-Free DNase Set, and methylated DNA is recovered while preserving methylation status for downstream bisulfite conversion. PCR inhibitors such as divalent cations and proteins are removed in three wash steps, leaving nucleic acids suitable for PCR and real-time PCR. Typical circulating DNA concentration in human plasma ranges from 1–100 ng/ml.

QIAGEN specifies storage at 2–8 °C for QIAamp Mini Columns (stable for at least one year after delivery), 15–25 °C for buffers (up to one year), and dissolved carrier RNA in Buffer AVE at 2–8 °C for up to 48 hours.