Oro-Sep Cartridges for Oligonucleotide Purification
Orochem has the following purification options available to remove the impurities generated during the synthesis of modified oligonucleotides. Which purification method is employed depends on how the oligonucleotide is modified and how it will be used
1) Desalting
Desalting procedures remove inorganic salts, traces of organic compounds, low molecular weight impurities, and short failure sequences. Desalting is accomplished by taking advantage of size (molecular weight) or solubility differences.
2)Gel Filtration
Gel filtration removes low molecular weight molecules, inorganic salts and very short failure sequences. Purification occurs by passing a sample through a Sephadex® column, which separates molecules based on size.
2)DMT Adsorption
These cartridge work on the principle of adsorption the dimethyltrityl (DMT) group of the trityl-on oligonucleotide while non-DMT bearing failure sequences, by-products, and other impurities wash through. The DMT group is removed with mild acid, allowing the purified, detritylated oligonucleotide to be eluted.
These cartridge not only eliminates salts and trace organic impurities from the crude oligonucleotide, but also provides pure oligonucleotides for sequencing primers, PCR primers, hybridization probes, and gene constructions.
Basic Protocol

• Loading of the ligonucleotide in a 0.1 M triethyl ammonium acetate (TEAA)
• Elution of trityl-off failures in 15% acetonitrile/ 85% 0.1MTEAA
• Detritylation using 0.5% trifluoroacetic acid (TFA)
• Elution of trityl-off oligo product using acetonitrile gradient
• Wash with 100% acetonitrile