Benefits of our Plasmid Miniprep Kit

ChargeSwitch Pro Plasmid Miniprep Kit
  • Exceptionally robust performance—100% ethanol-free, guanidinium-free, organic solvent-free, aqueous protocol
  • Improved downstream performance data—faster enzyme kinetics, higher transformation efficiency, and higher degree of supercoiling
  • Fast, hassle-free set-up—complete kit with no ethanol required and elution tubes provided

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ChargeSwitch technology developed to overcome current limitations of Plasmid Minipreps

Researchers have been performing plasmid minipreps for years—but they could be using an easier, faster, safer method and getting better results. Today, the majority of the plasmid miniprep methods in use require a silica membrane for DNA binding and purification. While generally effective, this technology suffers from a number of limitations, including the possible introduction of contaminants into downstream applications, compromising your results (Table 1). Other methods employ anion exchange to purify plasmid DNA. This method is effective but is expensive, slow, and requires a precipitation step during which you may lose sample. But, there is a better way—ChargeSwitch® pH-dependent technology. Now you can purify plasmids without introducing inhibitors such as ethanol and chaotropic salts and obtain a cleaner purified plasmid for optimal downstream performance in PCR, sequencing, and transformation experiments.

Table 1. ChargeSwitch Pro Plasmid Miniprep Kits overcome the limitations of traditional plasmid purification

LimitationImplicationHow this affects you
Ethanol and guanidinium HCl are required to facilitate binding and removal of contaminantsBoth reagents are difficult to remove from sample once introducedAdditional steps such as centrifugation or "smack and dab" methods are required, but typically not 100% effective
Both reagents are known to inhibit enzymatic activity in low concentrationsReduced enzymatic activity and overall poorer enzymatic performance in common applications such as PCR, restriction digestion, and cloning
Both reagents are hazardous or require proper disposal in common applications
Binding mechanism is nonspecific adherence; ion exchange is the preferred format for quality performanceThe ability to selectively purify the plasmid DNA is limitedReduced purity and performance in common applications
Delicate glass-fiber membranesThe shear forces involved in centrifugation can result in release of small glass-fiber particulatesOptical density shifts affects quantitation
Fibers can damage microcapillary instrumentation
Plasmid integrity is compromisedSupercoiled plasmid forms are generally preferred for optimal performance


ChargeSwitch-Pro Plasmid Miniprep protocol

The ChargeSwitch protocol retains the ease and familiarity of common silica spin-column protocols with binding, washing, and elution steps (Figure 1, Table 2), making adapting to the ChargeSwitch method effortless.

Just add your sample to the Plasmid Miniprep Kits

The ChargeSwitch-Pro Plasmid Miniprep Kit provides all reagents and components required to process your sample. There is no need to add ethanol to any buffers or search for additional collection tubes. All you need to supply is your E. coli culture.

The easy-to-follow ChargeSwitch-Pro Plasmid Miniprep Kit protocol

Figure 1. The easy-to-follow ChargeSwitch-Pro Plasmid Miniprep Kits protocol.

Table 2. ChargeSwitch Pro Plasmid Miniprep Kits specifications.

TechnologyChargeSwitch-Coated membrane
Culture Volume1–5 mL (LB or TB)
Speed<30 min
Purity (A260/A280)1.7 – 2.0
YieldUp to 20 ug
Plasmid SizeUp to 20 kb
Plasmid Copy NumberHigh or low copy
ProcessingCentrifugation or vacuum

Improve the downstream performance of your Plasmid Miniprep Kits

Since ChargeSwitch Technology does not require the use of ethanol, chaotropic salts, or organic solvents for nucleic acid purification, the resulting DNA is free of potentially inhibitory compounds, improving DNA integrity for better downstream PCR performance (Figure 2). Expect to see improved cloning due to higher transformation efficiencies (Figure 3), faster restriction enzyme digestions (Figure 4), sequencing reads in excess of 800 base pairs with Phred scores >20, and a higher degree of supercoiling (Figure 5).

The ChargeSwitch-Pro Plasmid Miniprep kit vs a competitor

Figure 2.  ChargeSwitch-Pro reagents do not contain inhibitory components that may interfere in downstream PCR reactions. The inhibitory reagents used in most plasmid purification techniques are difficult to detect when measuring DNA quality on gels or by UV spectrophotometry. They can, however, inhibit PCR. The action gene was amplified by PCR from human placental DNA, in a 50-µL reaction spiked with varying volumes of ethanol, isopropanol (IPA), competitor wash buffers, guanidinium isothiocyanate (GTC) and ChargeSwitch wash buffer. Ten microliters of amplified product run on a 1% agarose gel and stained with ethidium bromide.


ChargeSwitch-Pro Plasmid Miniprep Kit

Figure 3. Higher transformation efficiencies with plasmid purified using the ChargeSwitch-Pro Kit. The ChargeSwitch-Pro Plasmid Miniprep Kit and a competitor silica prep kit (Q) were used to purify pUC19 plasmid DNA from 5 mL of LB culture. One Shot® TOP10 Chemically Competent E. Coli was transformed using 10 pg of the purified pUC19 plasmid DNA, or OneShot TOP10 Electrocomp E. Coli was transformed with 5 pg of the purified pUC19 plasmid DNA. pUC19 plasmid DNA supplied with the competent cells was used as a control. Error bars represent 1 SE (n=12).

ChargeSwitch-Pro Plasmid Miniprep kit vs a competitor silica prep kit

Figure 4.  Improved restriction enzyme digestion kinetics with plasmid purified using the ChargeSwitch-Pro Kit. ChargeSwitch-Pro Miniprep column-purified DNA (C) can be digested faster than DNA purified using a silica column from a competitive kit (Q), pUC19 (A) or pLadder (B) purified with the ChargeSwitch-Pro kit were completely digested in about 30 min, whereas the silica-purified sample was only partly digested after 90 min.


ChargeSwitch-Pro Plasmid Miniprep Kit offers high quality supercoiled plasmid DNA

Figure 5.  Higher quality of supercoiled plasmid DNA. Supercoiled plasmid DNA represents a measure of both purity and how greatly a sample is treated during purification. ChargeSwitch-Pro purified plasmid exhibits a higher degree of supercoiling versus a silica-based prep from Competitive Q, which displays both supercoiled and nicked species of plasmid DNA.

For Research Use Only. Not for use in diagnostic procedures.