The Serum/Plasma Circulating DNA Kit was created specifically for isolating circulating DNA from serum/plasma. The Kit offers high purity and stable quality DNA free of proteins and other organic compounds thanks to its unique silica membrane innovation and buffer solution. Its method of extraction does not include phenol or chloroform. Purified DNA can be utilized directly in molecular biological experiments like PCR, Southern Blot, and library building. Carrier RNA can help nucleic acids bind to the spin column membrane, especially if the sample contains a small number of target molecules. The sample volume required is between 100 and 200 µl.
Storage:
Store at room temperature (15-25℃)
Components:
Specifications:
| Sample amount | 100-200µl |
| Features | No phenol / chloroform extraction. Purified DNA can be used directly for PCR, Southern Blot and NGS. Carrier RNA can enhance binding of nucleic acids to the spin column membrane, especially if there are very few target molecules in the sample. |
| Application | The purified DNA can be used directly for molecular biological experiments such as PCR analysis, Southern Blot and library construction. |
| Sample type | Serum, plasma |
Ensure that ethanol (96-100%) has been added into Buffer GD and Buffer PW as indicated on the tag of the bottle before use.
- Transfer 100-200 µl of plasma/serum sample in a 2 ml tube (not supplied). If less than 100 μl, please make up with Buffer GA to 100μl.
- Add 20 µl Proteinase K and mix well by vortexing.
- Add 200 µl Buffer GB (optional: add 1µl Carrier RNA working solution), mix thoroughly by upsides and down. Incubate at 56°C for 10 min, vortex every 3 min. Briefly centrifuge the microcentrifuge tube to remove drops from the inside of the lid.
- Add 200µl ethanol (96%-100%). Mix thoroughly by upsides and down. Incubate at room temperature for 5 min. Briefly centrifuge the microcentrifuge tube to remove drops from the inside of the lid.
- Pipet the mixture from step 4 into the Spin Column CR2 (in a 2ml collection tube) and centrifuge at 12,000 rpm (~13,400 × g) for 30 s. Discard flow-through and place the spin column into the collection tube.
- Add 500 μl Buffer GD (Ensure ethanol has been added) to Spin Column CR2, and centrifuge at 12,000 rpm (~13,400 × g) for 30 s, then discard the flow-through and place the spin column back to the collection tube.
- Add 600 μl Buffer PW (Ensure ethanol has been added) to Spin Column CR2, and centrifuge at 12,000 rpm (~13,400 × g) for 30 s. Discard the flow-through and place the spin column back to the collection tube.
- Repeat step 7.
- Centrifuge at 12,000 rpm (~13,400 × g) for 2 min to dry the membrane completely. Open lid of CR2 and stay at room temperature for a while to dry the membrane completely.
- Place the Spin Column CR2 in a new clean 1.5 ml microcentrifuge tube, and pipet 20-50 μl Buffer TB to the center of the membrane. Incubate at room temperature (15-25°C) for 2-5 min, and then centrifuge for 2 min at 12,000 rpm (~13,400 × g).
- (Optional) For increased DNA concentration, add the solution obtained from step 10 to the center of membrane again. Incubate at room temperature (15-25°C) for 2-5 min, and then centrifuge for 2 min at 12,000 rpm (~13,400 × g).
Note: The volume of elution buffer should not be less than 20 μl, or it may affect the recovery efficiency. What’s more, the pH value of elution buffer has influence in eluting, we suggest use buffer TB or distilled water (pH 7.0-8.5) to elute DNA. For long-term storage of DNA, eluting in Buffer TB and storing at -20°C is recommended.
