HiSpeed Plasmid Kits

No. Ethanol is not recommended when using the QIAprecipitator module of the HiSpeed Plasmid Kits for DNA precipitation. The finer precipitates formed with ethanol are likely to clog the QIAprecipitator.

When using the QIAprecipitator module of the HiSpeed Plasmid Midi- or Maxi Kits, make sure to dry the membrane by pressing air through the QIAprecipitator at least twice. Dry the outlet nozzle of the QIAprecipitator with absorbent paper. This will prevent carry-over of alcohol into the eluate and enable optimal performance of the extracted DNA downstream.

Do not load eluate from from several columns on the QIAprecipitator, and be sure that the correct precipitator size is used for the corresponding HiSpeed Tip. Do not replace the isopropanol with ethanol for precipitation, since the use of ethanol will lead to a finer precipitate that can clog the module.

To prevent breakage and leakage of the module it is important to avoid excessive force, bending, or twisting while attaching the QIAprecipitator to the syringe. Do not stress the inlet by resting one edge of the QIAprecipitator on a hard surface (e.g., the edge of a sink) and depressing the syringe plunger. Always apply gentle, even, pressure perpendicularly to the QIAprecipitator.

When using the silica-based QIAprep Spin Miniprep Kit, a protocol is contained in the QIAprep Miniprep Handbook, in Appendix C: Special Applications. The protocol is called: 'Purification of plasmid DNA prepared by other methods'.

For our anion-exchange based Plasmid Purification Kits, a protocol can be accessed online at our Plasmid Resource Center, and is called 'Re-Purification of Plasmid DNA Prepared by Methods other than QIAGEN Tips'.

The composition of Buffer TE is:

• 10 mM Tris·Cl, pH 8.0
• 1 mM EDTA

Buffer TE is a commonly used DNA resuspension and storage buffer. It is supplied in QIAGEN's Endofree Plasmid Kits, and used for plasmid DNA resuspension in combination with other QIAGEN Plasmid Kits. Details on buffer preparation and storage are presented in Appendix B of the QIAGEN Plasmid Purification Handbook.

The lowest elution volume that should be used for both the QIAprecipitator Midi and the Maxi Module provided in the HiSpeed Plasmid Kits is 500 ul. The official elution volume for both modules is 1 ml. If a higher DNA concentration is desired and a reduction in yield of up to 10% is acceptable, the elution volume can be reduced. Elution volumes smaller than 500 ul will lead to incomplete wetting of the QIAprecipitator membrane and further reduced DNA yields.

A precipitate forming upon adding LyseBlue reagent to Buffer P1 is a normal observation. This precipitate will completely dissolve after addition of Buffer P2. Please be sure to shake Buffer P1 vigorously before use to completely resuspend LyseBlue particles.

The composition of Buffer P1 is:

• 50 mM Tris·Cl, pH 8.0
• 10 mM EDTA
• 100 µg/ml RNase A

After RNase A addition, the buffer should be stored at 2–8°C.

Buffer P1 is the resuspension buffer used in a variety of QIAGEN kits for plasmid DNA purification. Details on buffer preparation and storage are presented in Appendix B of the QIAGEN Plasmid Purification Handbook.

The composition of Buffer P3 is:

• 3.0 M potassium acetate, pH 5.5

Buffer P3 is the neutralization buffer used in QIAGEN's anion-exchange based Kits for plasmid preparation. Details of buffer preparation and storage are presented in Appendix B of the QIAGEN Plasmid Purification Handbook.

Buffer QC is the wash buffer used in QIAGEN Plasmid Kits for plasmid purification and in QIAGEN Blood & Cell Culture kits.

The composition of Buffer QC is:

• 1.0 M NaCl
• 50 mM MOPS, pH 7.0
• 15% isopropanol (v/v)

To make 1 liter of solution, dissolve 58.44 g NaCl, 10.46 g MOPS (free acid) in 800 ml distilled water. Adjust the pH to 7.0 with NaOH. Add 150 ml pure isopropanol. Adjust the volume to 1 liter with distilled water. Store at 15–25°C.

Buffer QBT is the equilibration buffer used in QIAGEN Plasmid Kits for plasmid purification and in QIAGEN Blood & Cell culture kits.

The composition of Buffer QBT is:

• 750mM NaCl • 50 mM MOPS, pH 7.0
• 15% isopropanol (v/v)
• 0.15 % Triton® X-100 (v/v)

To make 1 liter of solution, dissolve 43.83 g NaCl, 10.46 g MOPS (free acid) in 800 ml distilled water. Adjust the pH to 7.0 with NaOH. Add 150 ml pure isopropanol and 15 ml 10% Triton X-100 solution (v/v). Adjust the volume to 1 liter with distilled water. Store at 15–25°C