OLIGONUCLEOTIDE SYNTHESIS ON POLYSTYRENE-GRAFTED POLY(TETRAFLUOROETHYLENE) SUPPORT

Supports consisting of a thin layer (2-10%) of polystyrene (PS) grafte d onto a poly(tetrafluoroethylene) (PTFE) core are an interesting alte rnative to controlled pore glass (CPG) carriers in oligonucleotide syn thesis. The beads are mechanically stable, do not show significant swe lling, and allow effective removal of substrates by short washing step s with organic solvents. PTFE-PS as an organic polymer has generally m ore hydrophobic properties than inorganic polymer supports and, theref ore, is well compatible with organic solvents such as anhydrous MeCN. We found PTFE with a content of 2-3% PS graft to be a very good suppor t for the synthesis of oligonucleotides of extended length. In compari son, PTFE with 5-10% grafted PS is especially useful for large-scale s yntheses. Functionalization procedures minimized in the extent of side reactions are described as well as examples for the use of the suppor ts in syntheses of oligonucleotides both on large scale and of extende d chain length.