ChargeSwitch Nucleic Acid Purification Technology

Easy on Your Sample. Easy on You.

Invitrogen ChargeSwitch nucleic acid purification technology is the simplest, cleanest, and most effective means of purifying both DNA and RNA, and can be configured in a range of product formats including simple manual purification methods as well as high-throughput automated applications. ChargeSwitch technology is based on a simple ion-exchange mechanism that uses a surface ligand that is positively charged at low pH, and neutral at pH 8.5 to bind and elute plasmid.

Learn about ChargeSwitch nucleic acid purification technology

How ChargeSwitch Technology Works

ChargeSwitch nucleic acid purification technology (CST) takes advantage of a unique ionizable (switchable) coating that can be covalently affixed to the surface of magnetic or nonmagnetic beads, membranes, or even plastic tubes and plates. ChargeSwitch-based kits require just four simple steps (Figure 1) to extract nucleic acids from a wide variety of sources, including bacteria, tissues, cells, blood, forensic sample and buccal cells.

ChargeSwitch-based protocols

Figure 1. Protocol. The ChargeSwitch Technology features a charged nucleic acid–binding surface that is “switchable” by changing the pH of the surrounding buffer. At low pH, the surface is positively charged and binds the negatively charged nucleic acid backbone, allowing easy removal of proteins and other contaminants using a simple wash step.

ChangeSwitch technology formats

ChargeSwitch technology can be used in a variety of formats—from magnetic beads to coated plates to spin columns. Initially ChargeSwitch technology was available in the format of magnetic beads. All are water-based and do not employ the use of harsh reagents such as chaotropicsalts , ethanol, or organics and isopropanol precipitation.



ChargeSwitch technology was also developed to coat a membrane for use in a column format for plasmid minipreps and PCR clean-up. The ChargeSwitch-Pro Plasmid miniprep and PCR Clean-up protocols retain the ease and familiarity of the common silica spin column protocol with a binding, washing, and elution step, making adapting to the ChargeSwitch method effortless.

Improved DNA and RNA integrity for downstream applications

Unlike classic ion exchange or silica-based nucleic acid purification technologies, ChargeSwitch-based DNA and RNA purification is 100% water-based and does not require the use of ethanol, chaotropic salts, organic solvents or time consuming precipitation steps. Purified, the resulting nucleic acid lacks these potentially inhibitory compounds—improving DNA or RNA integrity for downstream performance in applications such as PCR (see Figure 2), qPCR, RT-PCR, Restriction Enzyme digestion, STR analysis, sequencing, whole genome amplification (WGA), and other similar applications. As a result, ChargeSwitch-based protocols can offer significant performance benefits. Additionally, it excels at extracting DNA from forensic samples and buccal scrapes.

ChargeSwitch technology comparison for plasmid purification

Figure 2. ChargeSwitch technology for plasmid purification. The inhibitory reagents used in most plasmid purification techniques are difficult to detect when measuring DNA quality on gels or by UV spectophotometry. They can, however, inhibit enzymatic reactions. The actin gene was amplified by PCR from human placental DNA in a 50 µL reaction spiked with varying volumes of ethanol, isopropanal (IPA) and a 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.

Product Selection Guide

Nucleic Acid SpeciesApplicationProduct
Genomic DNAAnimal tissues and cellsChargeSwitch gDNA Mini Tissue Kit
Genomic DNABacteriaChargeSwitch gDNA Mini Bacteria Kit
Genomic DNAPlant tissues and cells, and fungiChargeSwitch gDNA Plant
Genomic DNABuccal cellsChargeSwitch gDNA Buccal Cell Kit
Genomic DNAForensic samplesChargeSwitch Forensic DNA Purification Kit
Genomic DNABlood and blood-derived samplesChargeSwitch gDNA 50–100 µL Blood Kit
Plasmid DNAMiniprep ColumnsChargeSwitch Pro Plasmid Miniprep Kit
DNAPCR reaction clean-upChargeSwitch PCR Clean-Up Kit