CIRCULATING NUCELIC ACID ISOLATION
CBI offers a new system for the isolation of circulating nucleic acids (DNA and RNA) from liquid biopsies, cells and tissues. Our DNA isolation kit is based on a new DNA Binding Matrix that captures circulating DNA from biofluids (serum, plasma, urine, amniotic and cerebrospinal fluids) without addition of salts and/or chaotropic agents.
No Proteinase K digestion is required. Standard volume of liquid biopsy for DNA isolation is 2-5 ml. Scale up to 50 ml of liquid can easily be done.
We have developed a new method of cell-free DNA (cfDNA) isolation from plasma, serum, and urine samples based on a dual-functional substance that binds DNA under physiological conditions (e.g., directly from biological fluids) where it is absorbed to a solid phase matrix. Current commercial cfDNA isolation kits employ a traditional silica-chaotropic salt approach and often suffer from lot-to-lot surface differences of silica that result in low extraction efficiency of small DNA fragments. Our approach eliminates this problem.
Our circulating DNA isolation procedure includes three conventional steps:
• DNA binding: simply add SubX and Binding Matrix to your bioliquid sample and rotate for a few minutes;
• Washing: 3 brief vortex-spins;
• Elution: DNA is easily eluted in a small volume (30-50ul) of buffer.
cfDNA-isolation approach using bi-functional substance has three major innovative elements:
1- Fast and effective biding of exosomes and cell-free nucleic acids in physiological conditions (directly in bioliquids);
2- Unbiased isolation of both exosomes components and cfDNA fragments from the same sample;
3- No ultracentrifugation and dilution of the starting material is required, thus allowing to develop convenient single tube procedure.
Figure 1. cfDNA isolated from 4 ml urine samples. DNA was quantified using Qubit HS DNA Assay.
Figure 2. cfDNA isolation from 0.2 ml plasma. DNA yield was estimated by qPCR for single copy gene 36B4.