Plasmid Miniprep
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Materials
Solution II: 0.2N NaOH/1% SDS
Solution III: 3 M KOAc, pH4.8
RNAseA (DNAse free) 10 µg/mL
Chloroform/Isoamyl alcohol (1/25 v/v)
Isopropanol
70 % ethanol
13% PEG8000
Procedure
1) Culture 5 mL of bacteria o.n. in LB + 100 mg/mL ampicillin.
2) Spin down 1.5 mL of each culture (5,000 rpm x 3 min.) Discard supernatant. Add additional 1.5 mL of cell suspension and spin a second time.
3) Resuspend pellet in 100 µL of H2O.
4) Add 300 µL of Solution II. Mix, incubate on ice for 5 min.
5) Add 300 µL of Solution III. Mix, incubate on ice for 5 min.
6) Spin 5 min at maximum speed, 4°C. Save supernatant in a fresh tube.
7) Add 10 µL of RNAseA, incubate at 37°C x5 min.
8) Extract with 1 volume of chloroform x1, spin 2 min. Transfer aqueous phase to a new tube.
9) Add 1 volume of isopropanol, mix. Spin at max. speed x 2 min.
10) Rinse with 70% ethanol. Dry pellet. Resuspend in 80 µL of T.E.
Optional (for DNA sequencing)
11) Add 20 µL of 4 M NaCl, mix. Add 100 µL of 13% PEG, mix. Incubate on ice x20 min.
12) Spin at max speed, 4°C x15 min. Rinse pellet with 70% ethanol. Dry pellet.
13) Resuspend in 50 µL H2O.