Nucleic Acid Capture Assays
Streptavidin-coupled Dynabeads® are ideal for capture of low abundance DNA/RNA sequences from clinical samples (blood, stool, cerebrospinal fluid etc.). The method offers several advantages, including the removal of extraneous DNA/RNA and inhibitory substances as well as concentration of your diluted and precious target into a small volume for further analysis. Depending on the probe, target and specific application, the capture approach can be either direct or indirect.
Viral RNA, DNA from fastidious bacteria, mutated sequences and microsatellites and many other specific targets are captured from complex samples using streptavidin-coupled Dynabeads® and a biotinylated probe.
Dynabeads® show excellent reaction kinetics comparable to liquid-phase kinetics, and are particularly well suited for automated sample preparation and handling. Their high magnetic mobility and low sedimentation rate make them ideal for robotic handling.
Direct or indirect capture?
Depending on your target molecule and the specific application, the direct or indirect capture method can be applied.
For some applications, using a pre-coupled ligand for direct capture allows you to reuse the Dynabeads® and thus further reduce sample preparation costs.
An indirect approach can be of benefit when the concentration of your target is low, the specific affinity is weak or the binding kinetics is slow. In the indirect approach, the probe/ligand is allowed to bind to the target in suspension prior to addition of the beads.
A monolayer of streptavidin is covalently coupled to the Dynabeads®, ensuring negligible leakage that could otherwise disturb your assay.
- Meng Q. et al. (2001). Automated multiplex assay system for simultaneous detection of hepatitis B virus DNA, hepatitis C virus RNA and human immunodeficiency virus type 1 RNA. J.Clin.Microbiol. 39(8):2937-2945.
- Pollock GS. et al. (2001). Effects of early visual experience and diurnal rhythms on BDNF mRNA and protein levels in the visual system, hippocampus and cerebellum. J. Neurosci. 21(11):3923-3931.
- Miyashiro I. et al. (2001). Molecular strategy for detecting metastatic cancers with use of multiple tumor-specific MAGE-A genes. Clin. Chem. 47(3):505-512.
- Stevens SJC. et al. (1999). Monitoring of Epstein-Barr virus DNA load in peripheral blood by quantitative competitive PCR. J.Clin. Microbiol. 37:2852-2857.
- Mangiapan G. et al. (1996). Sequence capture-PCR improves detection of mycobacterial DNA in clinical specimens. J. Clin. Microbiol. 34(5): 1209-1215.
- Dong SM. et al. (2001). Detection of colorectal cancer in stool with the use of multiple genetic targets. J Natl Cancer Inst. 93(11): 858-865.
- Refseth UH. et al. (1997). Hybridization capture of microsatellites directly from genomic DNA. Electrophoresis. 18(9):1519-1523.