Qiagen Buffers

Formulas for Qiagen Kit Buffers

Do not autoclave solutions containing isopropanol or MOPS; use sterile filtration if necessary.

Buffer P1

• 50 mM Tris-HCl pH 8.0
• 10 mM EDTA
• 100 μg/ml RNaseA

The buffer and RNaseA can also be ordered from Qiagen separately (catalog numbers 19051 and 19101).

Buffer P2

• 200 mM NaOH
• 1% SDS

Buffer P3 (not for spin columns, but for Qiatips, midi, maxi, giga kits)

• 3.0 M potassium acetate pH 5.5

Buffer N3

• 4.2 M Gu-HCl
• 0.9 M potassium acetate
• pH 4.8

Buffer PB

• 5 M Gu-HCl
• 30% ethanol
• (maybe add 10mM Tris-HCL PH 6.6, and that is better)

Buffer PE

• 10 mM Tris-HCl pH 7.5
• 80% ethanol

Buffer QBT equilibration buffer

• 750 mM NaCl
• 50 mM MOPS pH 7.0
• 15% isopropanol
• 0.15% triton X-100

Buffer QC wash buffer

• 1.0M NaCl
• 50 mM MOPS pH 7.0
• 15% isopropanol

Buffer QF elution buffer

• 1.25M NaCl
• 50 mM Tris-HCl pH 8.5
• 15% isopropanol

Buffer QN

• 1.6M NaCl
• 50 mM MOPS pH 7.0
• 15% isopropanol

Buffer FWB2

• 1M potassium acetate, pH 5.0

(Source: [1], US Patent 6,383,393)

The LyseBlue indicator dye added to some of the buffers is Thymophthalein, pH shift from colorless to blue at pH 9.3

Recycling Qiagen Columns

The blue and purple Qiagen columns are identical in formulation. They are interchangeable and can be reused multiple times after treatment with hydrochloric acid, re-equilibration, and wash. Very likely this protocol can be used with other similar columns. Unused columns can be cheaply purchased in bulk from Epoch Biolabs.

The reuse protocol is:

• Save the collection tubes and columns after elution of DNA
• Fill the column with 700 μl of 1 M HCl
• Cap and store in an airtight container for at least 24 hours (less than a month)
• Wash the columns and collection tubes in a large beaker of water
• Assemble the column and collection tube and wash the column with 700 μl of DI water, discarding the water
• Repeat
• Fill the column with 700 μl of buffer QBT and spin down, discarding the buffer
• Place the columns in an airtight plastic bag for storage
• Wash the collection tubes, air dry, and store them for reuse

References: PMID 17373483 Davidson Column Recycling instructions