● High-purity: The purified plasmid DNA can be directly used in high-precision experiments such as transfection.

● Large sample amount: 5-15 ml of bacteria culture medium can be processed in one practice, so that the efficiency of the experiment is improved.

● Fast: Simple procedure with minimal steps to minimize the operation time.

● High efficiency: More than 85% of plasmid DNA can be purified from E.coli.

The TIANpure Midi Plasmid Kit adopts a specific designed Filtration CS in addition to the spin column-based extraction kit, which can remove trace proteins and other impurities during the plasmid DNA extraction. The purified high-purity plasmid DNA yield can be up to 70 μg, and can be applied in high-precision molecular biology experiments such as the transfection of large amount of plasmids into animal culture cells.

TIANpure Midi Plasmid Kit can be stored dry at room temperature (15-30°C) for up to 15 months without showing any reduction in performance and quality. If any precipitate forms in the buffers, it should be dissolved by warming the buffers to 37°C before use. RNase A (10 mg/ml) can be stored for 15 months at room temperature (15-30°C). After adding RNase A, Buffer P1 is should be stored at 2-8°C and is stable for 6 months.

● Add the provided RNase A solution to Buffer P1 before use (use 1 vial RNase A per bottle Buffer P1), mix, and store at 2-8°C.

● Check Buffer BL, P2 and P3 before use for salt precipitation. If necessary, dissolve the buffer by warming at 37°C.

● Avoid direct contact of Buffer P2 and P3, immediately close the lid after use.

● All centrifugation steps are carried out at 12,000 rpm (~13,400 ×g) in table-top centrifuge at room temperature.

● The amount of extracted plasmid is related to cells concentration and plasmid copy. If working with low copy vectors or large plasmid (>10 kb), it may be beneficial to increase culture volume and to increase Buffer P1, P2, and P3 in proportion. Warm the Buffer TB to 65-70°C before use. Prolong adsorption and elution time properly to increase extraction efficiency.

● Use Buffer BL to treat spin columns could activate silica membrane at maximum degree and higher yield.

● After treated with Buffer BL, use the Spin Column soon, since long-term placement may affect the purifying effect.

The recovered DNA fragments can be detected by agarose gel electrophoresis and ultraviolet spectrophotometer. DNA should have a significant absorption peak at OD₂₆₀. OD₂₆₀ value of 1 is equivalent to about 50 μg/ml double stranded DNA and 40 μg/ml single stranded DNA. The OD₂₆₀/ OD₂₈₀ ratio should be 1.7-1.9. If ddH₂O is used for the elution instead of the elution buffer, the ratio will be lower, because the pH value and the presence of ions will affect the light absorption value, but it does not mean the purity is low.