DNeasy Blood and Tissue Kits for DNA Isolation

Please see the article High-throughput DNA purification with DNeasy 96 - more than just mouse tails for this data.

Dedicated QIAcube kits are the RNeasy Mini QIAcube Kit, QIAamp DNA Mini QIAcube Kit, the QIAamp DNA Blood Mini QIAcube Kit, and the QIAamp Viral RNA Mini QIAcube Kit. In addition to these kits are the QIAamp PowerFecal Pro DNA QIAcube Kit, the DNeasy PowerSoil Pro QIAcube Kit using Power technology, and the DNeasy Blood & Tissue QIAcube Kit.

Alcohol precipitation is commonly used for concentrating, desalting, and recovering nucleic acids. Since less alcohol is required for isopropanol precipitation, this is the preferred method for precipitation of DNA from large volumes. In addition, isopropanol precipitation can be performed at room temperature, which minimizes co-precipitation of salt that interferes with downstream applications.

Procedure

1. Adjust the salt concentration, for example, with sodium acetate (0.3 M, pH 5.2, final concentration) or ammonium acetate (2.0–2.5 M, final concentration).
2. Add 0.6–0.7 volumes of room-temperature isopropanol to the DNA solution and mix well.
3. Centrifuge the sample immediately at 10,000–15,000 x g for 15–30 min at 4°C
4. Carefully decant the supernatant without disturbing the pellet.
5. Wash the DNA pellet by adding 1–10 ml (depending on the size of the preparation) of room-temperature 70% ethanol. This removes co-precipitated salt and replaces the isopropanol with the more volatile ethanol, making the DNA easier to redissolve.
6. Centrifuge at 10,000–15,000 x g for 5–15 min at 4°C.
7. Carefully decant the supernatant without disturbing the pellet.
8. Air-dry the pellet for 5–20 min (depending on the size of the pellet).
9. Redissolve the DNA in a suitable buffer.

Tip: Use a buffer with a pH of 7.5–8.0, as DNA does not dissolve easily in acidic buffers. Often distilled water can have an acidic pH. The addition of EDTA protects the DNA from DNase digestion.

Tip: High-molecular-weight DNA, such as genomic DNA, should be redissolved very gently to avoid shearing. If the DNA pellet does not dissolve easily, heat at 55°C for 1–2 h with gentle shaking.

If you have optimized the lysis conditions for a specific sample type, you can lyse the sample in your lysis buffer, and follow the Supplementary Protocol 'Purification of total DNA from crude lysates using the DNeasy Blood & Tissue Kit' (DY15), or the corresponding protocol in the Appendix of the QIAamp DNA Mini Kit and QIAamp DNA Blood Mini Kit Handbook.

QIAGEN Proteinase K is stable for up to 1 year after delivery when stored at room temperature. To prolong the shelf-life of Proteinase K, storage at 2–8°C is recommended.

For plant-based foods, such as soy, tofu, and cookies, DNA isolation has been successfully carried out using the DNeasy Plant Mini Kit. The QIAamp DNA Stool Mini Kit has been used for isolation of genomic DNA from highly processed foods, and foods that contain high levels of PCR inhibitors, such as chocolate. For meat and processed meats, such as sausage, we suggest the DNeasy Blood & Tissue Kit.

See also the QIAGEN News article "Detection of genetically modified soybean and maize in raw and processed foodstuffs", and the accompanying editorial "Detecting genetically modified organisms in food."

Efficient DNA isolation requires thorough sample disruption and digestion.

Although the QIAamp and DNeasy procedures requires no mechanical disruption of the tissue sample, the lysis time will be reduced if the sample is ground in liquid nitrogen or mechanically homogenized in advance. For mechanical homogenization, a rotor–stator homogenizer, such as the QIAGEN TissueRuptor, or a bead mill, such as the QIAGEN TissueLyser, can be used.

To improve digestion of tough tissue samples, Proteinase K incubation at 56°C can be performed overnight. DNA yields may be improved by increasing the amount of Proteinase K or by adding additional proteinase K after several hours of digestion.  

The expected yield of genomic DNA isolated from bacteria with the DNeasy Blood & Tissue Kit or the QIAamp DNA Mini Kit is approximately 10 ug of DNA per 2x 10⁹ bacterial cells. Note that yields of genomic DNA will vary depending on bacterial strain, quality of the starting material, growing conditions, and the amount of material processed.

Small amounts of RNA and DNA may be difficult to measure spectrophotometrically. Fluorometric measurements, or quantitative RT-PCR and PCR are more sensitive and accurate methods to quantify low amounts of RNA or DNA.

Fluorometric measurements are carried out using nucleic acid binding dyes, such as RiboGreen® RNA Quantitation Reagent for RNA, and PicoGreen® DNA Quantitation Reagent for DNA (Molecular Probes, Inc.).

The composition of Buffer AE is:

• 10 mM Tris-Cl
• 0.5 mM EDTA; pH 9.0.

Yes, we have the following protocols:

• Isolation of genomic DNA from mosquitoes or other insects using the QIAGEN Genomic tip (QG06).
• Purification of total DNA from insects using the DNeasy Blood & Tissue Kit (DY14).

Yes, we have the following protocols:

• Isolation of genomic DNA from compact bone using the QIAamp DNA Mini Kit (QA02)
• Isolation of genomic DNA from compact bone using the DNeasy Blood & Tissue Kit (DY01)
• Purification of genomic DNA from bones using the QIAamp DNA Micro Kit (QA39)
• Purification of archive-quality DNA from bone fragments using the Gentra Puregene Tissue Kit (PG38).

Yes, we have the following protocols:

• Isolation of genomic DNA from sperm using the QIAamp DNA Mini Kit; protocol 1 (QA03), long procedure
• Isolation of genomic DNA from sperm using the QIAamp DNA Mini Kit; protocol 2 (QA04), short procedure
• Purification of total DNA from animal sperm using the DNeasy Blood and Tissue kit; protocol 1 (DY02), long procedure
• Purification of total DNA from animal sperm using the DNeasy Blood and Tissue kit; protocol 2 (DY03), short procedure
• Purification of DNA from epithelial cells mixed with sperm cells using the QIAamp DNA Micro Kit (QA40).

Yes, please follow either of the User-Developed Protocols:

• 'Acetyl Cysteine (NALC) treatment of viscous samples' (QA13). This protocol is for use with the QIAamp DNA Mini Kit.
• 'Acetyl Cysteine (NALC) treatment of viscous samples using the DNeasy Blood & Tissue Kit' (DY06).

Yes, we have the following protocols:

• Isolation of genomic DNA from saliva and mouthwash using the QIAamp DNA Mini Kit; vacuum procedure (QA19v)
• Isolation of genomic DNA from saliva and mouthwash using the QIAamp DNA Mini Kit; spin procedure (QA19s)
• Isolation of genomic DNA from saliva using the DNeasy Blood & Tissue Kit; spin procedure (DY07)

Yes, please follow either of the User-Developed Protocols:

• 'Isolation of DNA from soft tissues using the TissueLyser and QIAamp DNA Mini Kit' (QA31), for use with the QIAamp DNA Mini Kit
• Purification of total DNA from soft tissues using the TissueLyser and the DNeasy Blood & Tissue Kit' (DY11), for use with the DNeasy Blood & Tissue Kit

Yes, please follow the User-Developed Protocol 'Isolation of genomic DNA from saliva using the DNeasy Blood & Tissue Kit; spin procedure' (DY07).

Yes, please follow the Supplementary Protocol 'Purification of DNA from cultured animal cells using the DNeasy 96 Blood & Tissue Kit' (DY12).