Bio-Rad Quantum Prep Plasmid Kits - Manual (Page 11)

2.3 Helpful Hints
1. It is recommended that the cells do not sit longer than five
minutes at step 3 (lysis) before proceeding to step 4.
Additionally, it is recommended that the cells do not sit longer
than ten minutes at step 4 (neutralization) before proceeding to
step 5.
2. Due to the fixed angle for most microcentrifuges, the matrix may
pellet against the side of the spin filter. For optimal elution of
DNA from the matrix in step 10 of the protocol, the elution
liquid (water or TE) should be applied at the highest portion of
the matrix near the side of the spin column.
3. The use of strains deficient in the endonuclease I gene product,
such as DH5αF', is recommended for improving the quality of
plasmid DNA prepared from minipreps.
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