Description
ProbeQuant G-50 Micro Columns use spin-column chromatography to provide a fast and reliable method for purifying labeled probes from unincorporated labeled nucleotides. In addition, a portion of the eluted DNA can be counted in a scintillation counter and compared to an unpurified sample to give an approximation of percent incorporation. The columns are designed for use in a microcentrifuge, come prepacked with Sephadex G-50 DNA grade and are pre-equilibrated in STE, which means that they are ready to use. They can accommodate samples ranging in volume from 25 μL to 50 μL. The resin used in these columns, Sephadex G-50 DNA Grade , can be used in a wide range of applications, including desalting DNA, buffer exchange, and removal of unincorporated nucleotides from end-labelled oligonucleotides. MicroSpin columns packed with Sephadex G-50 DNA Grade are ideal for the rapid purification of DNA for use in a wide range of applications, including desalting DNA, buffer exchange, and removal of unincorporated nucleotides from end-labelled oligonucleotides . Sephadex G-50 is one of five different G-types ranging from G-10 for small molecules to G-75 for larger molecules. Sephadex G-50 is a well-established size exclusion chromatography resin for desalting and buffer exchange of biomolecules > 30 000 molecular weight, and with a spin protocol can be used for DNA and oligo purification of molecules greater than 20 bases in length. Alternatively, Sephadex G-25 or Sephadex G-100 can be used. Sephadex G-25 has an exclusion limit of approximately Mr 5000, and with a spin protocol this means it can be used for any DNA greater than 10 bases in length. Sephadex G-100 DNA Grade has an exclusion limit of 25bp ds DNA. All these Sephadex types are therefore suitable for the purification of oligonucleotides or small DNA fragments following synthesis or a labeling reaction.
