The resin used in these columns, Sephadex G-50 DNA Grade, can be used for 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 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.

Sephadex G-25 DNA Grade, Sephadex G-50 DNA Grade, and Sephadex G-100 are all sold separately.