PowerPrep™ HP Plasmid Purification Kits

Mini, midi and maxipreps employ gravity flow columns. Marligen now offers midi and maxiprep kits with a convenient integrated prefilter in the columns for even greater convenience and speed (Figure 1B).

Neutralized lysates can be added directly to columns containing the prefilters, thereby combining lysate clarification and column loading into one simple step. Marligen’s PowerPrep™ HP Plasmid Megaprep and Gigaprep Kits use the same patented anion-exchange resins found in our other PowerPrep™ HP Purification products. They employ vacuum-actuated filter cartridges that dramatically improve throughput.

Technology

The procedure employs modified alkaline lysis and neutralization followed by ion exchange chromatography using a patented resin designed to provide excellent capacity, resolution and endotoxin removal. The resin has uniform particles with small pores that provide a large surface area to ensure reproducible performance, fast flow rates and high yield. Long spacer arms and high charge density ensure excellent separation from other cellular contaminants, including RNA and endotoxin. The resulting DNA is ultrapure and optimal for all applications, including those requiring the highest purity such as transfection into sensitive cell lines, automated sequencing and in vitro transcription.

Performance Characteristics

DNA purified with Marligen’s PowerPrep™ HP Kits is suitable for all applications, including even the most sensitive transfections. Figure 2 demonstrates that plasmid DNA purified with Marligen’s kits can be cut with EcoRI and completely religated. The unique design of these products results in DNA with exceptionally high yields and low levels of endotoxin, without additional steps or expense (Table 1.) Figure 3 demonstrates that high quality DNA prepared with these kits performs exceptionally well in transfection experiments, even with difficult cell lines such as Huh1. Each lot of product is routinely tested to verify purity, integrity, and column flow rate and binding capacity.

Fig. 2 Plasmid DNA (pBluescript IIKS) was prepared using the Marligen PowerPrep™ HP Plasmid Purification Kits. The DNA was digested with EcoR1 and ligated with a 1.65 kb DNA fragment. Lane 1: 1 kb Ladder Lane 2: DNA before ligation Lane 3-5: Ligation with 0.02, 0.05 and 0.1 units of T4 DNA ligase.

Table 1 Three independent laboratories performed studies comparing the yields and endotoxin levels obtained from Marligen’s PowerPrep™ HP MaxiPrep Kit and the Maxiprep kit from Competitor Q. All three studies determined that there were significantly higher yields of purified DNA using Marligen’s kits compared to Competitor Q. In addition, these researchers showed that endotoxin levels were lower in DNA purified using Marligen’s kits.

Fig. 3 This comparison of transfection efficiency with several cell lines using DNA prepared by various methods demonstrates that Marligen’s Prep yields DNA that offers superior performance in transfection.