Glen Report 11.23: New Columns for Expedite and LV Applications

Expedite Synthesizer

PE Biosystems has announced that the Expedite 8909 synthesizer and the 16-column add-on MOSS unit will continue to be produced and enhanced. The Expedite synthesizer currently uses Biosearch crimped columns which have not changed since the mid-1980s, despite some clear design shortcomings:

• The sealing surfaces are small, making occasional liquid leaks almost inevitable.
• The polypropylene fabric filter at each end may be a little frayed and a stray fiber could cause very occasional leaks of powder.
• The aluminum crimped seals may relax with time, compromising the seal.
• The crimps are difficult to remove when necessary.

Radical improvements are clearly overdue and we are happy to present the Glen Research version of the Expedite column.

• A single-piece body removes the need for seals and guarantees that liquid leaks can not occur.
• Polyethylene frits are precision-molded for accurate fit to ensure that no powder leaks can occur and for reproducible porosity to give accurate flows.
• For those researchers who wish to open the column, guide rings are provided to slice the end off the column with a tubing cutter (Cole Palmer Part No. 06438-90), allowing access to the frit for easy removal.

Our testing of these columns over many syntheses has confirmed that their performance is at least equal to that of the previous columns while column to column reproducibility is considerably improved. Both 1 µmole and 0.2 µmole/40 nmole versions are available in the new format.

Low Volume (LV) Columns

The Expedite synthesizer is extremely frugal in its use of reagents, enjoying a well-deserved reputation for providing low-cost oligos. This situation allows efficient use of monomers, especially expensive, unusual bases. In addition to use on the Expedite, testing of the new columns on ABI 394 synthesizers has allowed us to recommend the use of the 0.2 µmole and 40 nmole columns on the LV200 and LV40 cycles, respectively. It has been our conclusion for some time that the best synthesis cycle is the LV200 cycle and we are happy to now offer our unusual supports in columns which allow use of this cycle.

Catalog Numbers

Effective immediately, our regular Biosearch columns will be replaced with the new columns. Catalog numbers and pricing of the regular support columns will remain the same. Pricing remains the same for empty columns and replacement frits. New catalog numbers are shown below:

For accurate ordering of unusual supports in these new columns, we will add the letter E (for Expedite) to the regular catalog numbers. For example,

1 µmole and 0.2 µmole dabcyl columns would have catalog numbers as shown:

Pack of four 3'-Dabcyl-CPG columns (1µm) 20-5911-41E

Pack of four 3'-Dabcyl-CPG columns (0.2µm) 20-5911-42E

Product Information

Empty Synthesis Columns & Frits