The MagNA Pure LC Cartridge Seal is an adhesive film used for sealing the MagNA Pure LC Sample Cartridge for storage purposes. The Cartridge Seals can be used at -80°C to +37°C. To obtain a single sample without exposing others, simply cut through the cartridge seal of the desired well, then reseal the cartridge with a new Cartridge Seal.
The disposable plastics for the MagNA Pure LC Instrument meet stringent requirements: they are free of nucleases and amplification inhibitors (for PCR/RT-PCR), and are guaranteed to be inert to most chemicals used in life-science laboratories.
The purification of a target protein is often required to elucidate scientific questions about the function, structure, and interaction of a protein of interest. Protein purification is a series of procedures intended to isolate a single type of protein from a complex mixture. The starting material is usually a microbial culture or biological tissue. Protein purification is based on differences in protein size, physicochemical properties, and binding affinity. The most common technique in affinity purification involves engineering a sequence of 6 to 14 histidines into the N- or C-terminal (or even on an exposed loop) of the protein. Such polyhistidine stretches bind strongly to divalent metal ions such as nickel and cobalt. This effect can be used to separate proteins. Metal ions can be immobilized on a matrix using a chelator, which still allows the ion to interfere with the polyhistidine tag of the protein. When these his-tagged proteins are passed through a column containing immobilized metal ions, the proteins bind via the tag to the column. Nearly all untagged proteins pass through the column. The protein is released from the column by elution with either imidazole, which competes with the polyhistidine tag for binding to the column, or by a decrease in pH, which decreases the affinity of the tag for the resin. While this procedure is generally used for the purification of recombinant proteins with an engineered affinity tag, it can also be used for natural proteins with an inherent affinity for divalent cations.