BeaverBeads Circulating DNA Kit

Product Overview

The BeaverBeads™ Circulating DNA Kit isolates cell-free DNA from serum or plasma using superparamagnetic silica microspheres and pre-made buffers. Circulating DNA is present at very low concentration — the manufacturer reports roughly 10 ng per mL from normal human serum — and is fragmented, so the method is built around recovering as much of it as possible and concentrating it into the smallest workable volume.

Performance

Recovery above 85% across all sample volumes tested; elution to as little as 20 µL. The buffer system removes the PCR inhibitors and protein carry-over that otherwise limit downstream sensitivity, and the manufacturer reports consistent qPCR Ct values across replicates. Sample input is flexible from 0.2 to 5 mL of serum or plasma; the 100-reaction configuration listed here is set up for a 1 mL sample, with a scaling table in the manual for other volumes. Purified cfDNA is suitable for PCR amplification, sequencing and detection.

Workflow

Proteinase K and lysis buffer digest the sample for 10 minutes at 55 °C with intermittent vortexing. Isopropanol and beads are added, mixed at maximum speed and left 10 minutes at room temperature to bind. Beads are then washed once with washing buffer and twice with 75% ethanol, air-dried on the magnet for 10 minutes, and eluted in 50 µL of elution buffer pre-warmed to 55 °C (the manual notes elution can go as low as 20 µL when maximum concentration matters, at some cost in efficiency). Eluted cfDNA can be stored at −20 °C.

Kit contents

Supplied: BeaverBeads™ magnetic beads · Lysis Buffer · Washing Buffer · Elution Buffer · Proteinase K (dry powder) · Solution A (for dissolving the Proteinase K). Not supplied, prepared by the user: isopropanol (AR grade), approximately 0.5 mL per sample, and 75% (v/v) ethanol, approximately 3.8 mL per sample.

Equipment required

A 55 °C dry bath or water bath, a magnetic separator (BEAVER Cat. 60201 fits 1.5 mL, 2 mL and 15 mL tubes), a vortex mixer, 200 µL and 1000 µL single-channel pipettes, and one 1.5 mL and one 15 mL tube per sample. BEAVER's dry bath incubator (Cat. 2016C) with the 1.5 mL 6-well aluminum module (Cat. 90103) covers the heating step.

Handling and safety

Before first use, dissolve the Proteinase K powder in the specified volume of Solution A, tick the box on the bottle label, and store the reconstituted enzyme at 2–8 °C, or at −20 °C after aliquoting. Do not freeze the magnetic beads. Prepare 75% ethanol fresh — it should not be stored for more than 2 days. If precipitate appears in the Lysis Buffer, incubate 2 minutes at 37 °C before use. During the drying step, remove any residual liquid with a small-volume pipette; carry-over ethanol inhibits downstream enzymatic reactions.

For Research Use Only. Not for use in diagnostic or therapeutic procedures. Specifications and protocol are those published by the manufacturer, BEAVER Biomedical Engineering Co., Ltd.