HiPure Plasmid EF Midi Plus Kit

HiPure Plasmid EF Midi Plus Kit is the core product within the Magen high-concentration plasmid preparation branch. Designed for high-copy plasmids, the kit processes 25–50 mL of bacterial culture and recovers up to 500 µg of plasmid DNA. Its workflow combines cation-mediated selective plasmid precipitation with compact filter-column purification, reducing dependence on conventional silica-membrane binding capacity. Elution in 100–300 µL produces concentrated plasmid DNA, while centrifugation and vacuum formats accommodate different laboratory setups. The workflow supports transfection-grade DNA below 1 EU/µg and injection-grade DNA below 0.1 EU/µg.

Within the high-concentration branch, P1231 is the core choice when final DNA concentration is as important as total yield. HiPure Low Copy Plasmid EF Kit (P1230) uses an LN4 high-salt binding system for low- and ultra-low-copy plasmids, whereas HiPure Plasmid EF Maxi Plus Kit (P1233) extends concentrated recovery to 100–200 mL cultures with yields up to 1.5 mg. Laboratories prioritizing broad vector compatibility in a routine maxi-scale workflow should instead select P1156.

Specifications

Engineering Characteristics

High-concentration midi-scale recovery

The optimized silica-membrane system is designed to purify up to 500 µg of plasmid DNA from 25–50 mL bacterial cultures. A selectable elution volume of 100–300 µL supports DNA concentrations of up to 3 µg/µL, providing concentrated plasmid DNA for transfection and other concentration-sensitive workflows.

Spin and vacuum configurations

Two operating formats are available using the same purification chemistry. P1231 uses vacuum-assisted column loading and washing, while P1231B provides a centrifugation workflow for laboratories without a vacuum manifold. Both routes use the same final membrane-drying and concentrated elution structure.

Integrated lysate clarification

The dedicated Lysate Clear Midi Syringe removes suspended precipitates and cellular debris from the neutralized lysate before column loading. This clarification step reduces particulate loading on the silica membrane and supports stable processing of 25–50 mL bacterial cultures.

Two endotoxin-purity levels

The standard workflow produces low-endotoxin plasmid DNA with an endotoxin level below 1 EU/µg for direct use in cell transfection. The Additional Protocol uses ER2-mediated endotoxin binding and micellar aggregation followed by isopropanol recovery to reduce the endotoxin level to ≤0.1 EU/µg, producing endotoxin-free plasmid DNA suitable for animal injection and transfection of sensitive cells.

Technical Validation

The performance of the HiPure Plasmid EF Midi Plus Kit (P1231) was evaluated using medium- and high-copy plasmid cultures across input volumes ranging from 10 mL to 100 mL. Plasmid DNA was purified using the manual workflow in approximately 60 minutes and assessed by spectrophotometry, agarose gel electrophoresis and restriction digestion.

For the medium-copy plasmid, total yield increased from 22 µg with 10 mL culture to 78–80 µg with 50 mL and 192–195 µg with 100 mL. For the high-copy plasmid, P1231 recovered 63–65 µg from 10 mL, 264–270 µg from 50 mL and 532–564 µg from 100 mL. A260/A280 values remained between 1.80 and 1.90 across the tested culture volumes.

P1231 was further compared with a leading European-brand plasmid midi kit under matched conditions using three different plasmids. With 30 mL culture input and a 200 µL elution volume, P1231 recovered 99–116% of the plasmid DNA yield obtained with the reference kit.

P1231 produced 112.7–311.5 µg across the three plasmids, compared with 97.2–291.6 µg using the reference workflow. Both methods produced comparable purity, with A260/A280 values of 1.91–1.92 and A260/A230 values of 2.21–2.34 for P1231.Plasmid DNA purified with P1231 was compatible with HindIII restriction digestion across four different plasmid preparations. Repeated extractions performed at different culture volumes produced consistent digestion profiles, and no visible plasmid degradation was observed by agarose gel electrophoresis after storage at room temperature for five days. These results support P1231 as a scalable, high-concentration plasmid purification workflow for medium- and high-copy plasmids.

Kit Contents

Storage and Stability

The kit components can be stored dry at room temperature (15–25°C) and are stable for 24 months under these conditions. Buffer E2 and Buffer E4 may precipitate at low temperatures. Warm at 55°C until the precipitate is completely dissolved before use. After addition of RNase A, Buffer E1 is stable for 6 months when stored at 2–8°C.

For guidance on selecting between standard and low-endotoxin plasmid workflows based on copy number, culture input and processing format, please refer to the Plasmid DNA Kits Purchase Guide.