Table 1.
Commercial kits and main characteristics of six kits designed for cfDNA isolation and purification from biofluids.
| Kit name | Manufacturer | Additional and optional steps |
Advantages | Disadvantages | Protocol time |
|---|---|---|---|---|---|
| QIAamp® circulating nucleic acid kit | Qiagen | Proteinase K digestion treatment Recommended DNase I treatment for RNA downstream studies |
Allows purification and concentration of free-circulating DNA, RNA, miRNA, and viral nucleic acids from human plasma, serum, urine, or other cell-free body fluids (4–8 ml) exist in format DSP for IVD use | Requires 4ml of plasma | 3 h |
| NucleoSpin® Plasma XS kit | Macherey-Nagel | Proteinase K digestion treatment | Allows nucleic acid purification and concentration from serum, plasma, and bronchial lavage (up to 240 μl), also it allows to purify DNA from buccal swabs and dried blood spots specially designed purification column allowing elution volumes as low as 5 μl | - | 30min-1h |
| FitAmp™ plasma/serum DNA isolation kit | Epigentek | Proteinase K digestion treatment | Allows DNA isolation from plasma, serum and other body fluids (500 μl) | Low efficiencies compared with other kits [39] | 15-30 min |
| QIAamp DNA blood mini kit | Qiagen | Protease or proteinase K digestion treatment | Allows nucleic acid purification from serum, plasma and urine (from 200 μl), also it allows to purify DNA from buccal swabs and dried blood spots exist in format DSP for IVD use | - | 2-3 h |
| Maxwell 16 blood DNA kit | Promega | Allows nucleic acid purification from 500 μl. It can be used with the Maxwell® 16 Blood DNA purification system (IVD) which compiles with EU directive for in vitro diagnostic medical devices. |
The original protocol is designed for whole blood DNA isolation but not for plasma or serum. | 30 min-1h | |
| Automated QIAsymphony DSP circulating DNA kit | Qiagen | Allows purification of free-circulating DNA, from human plasma, serum, and urine (2-4 ml) 96 simultaneous samples in 6 h | Requires the QIAsymphony SP instrument | 6h |
QIAamp circulating nucleic acid kit (Qiagen, Hilden, Germany), the NucleoSpin® Plasma XS kit (Macherey Nagel, Düren, Germany), the FitAmp™ plasma/serum DNA isolation kit (Epigentek, Farmingdale, NY); QIAamp DNA blood mini kit (Qiagen, Hilden, Germany), and Maxwell 16 blood DNA kit (Promega, Madison, WI).