Oligo synthesis was conducted under the same conditions using glass wool as support. The scale was 12.8 nmol, for which 50 mg glass beads were used. Deprotection and cleavage as well as CBP purification were also the same except that only 20 mg (theoretically 5.12 nmol oligo) glass beads were used. The quantity of the oligo obtained was determined to be 168 ng (0.68 pmol) for the synthesis involving 20 mg glass beads. The overall yield for the entire 800-mer synthesis and purification was 0.013% (Entry 8, Table ), which is much lower than the value 0.38% obtained for glass wool. The reason is unclear but may be attributable to the loss of materials in the synthesis, deprotection, cleavage and purification process probably due to the increased difficulty to handle much smaller quantities of oligos.