*****Glen Research Glen Report*****

New products: Glen-Pak™ DNA Cartridge 3g and DNA 30mg 96-Well Plates

Since their launch in 2007, the Glen-Pak™ cartridges have been extremely well received. So well, in fact, that some of our customers have reported that they are omitting HPLC and PAGE purifications!

While the existing Glen-Pak DNA and RNA formats are capable of use in 96 well formats from 40 nmole through 1.0 µmole scale, many customers have asked for both a larger scale option (10-20 µmole) to be used in either one time or pre-purification DNA applications, as well as an integrated smaller scale (10 – 50 nmole) DNA purification filter plate that can be used in more standardized, robotic high throughput settings. We are happy to introduce two new products to meet these demands.

Glen-Pak™ Cartridge 3g:

The Glen-Pak DNA Cartridge 3g is a 20 mL syringe-type tube compatible with luer-type vacuum manifolds. This cartridge enables DMT-ON oligo purification on a scale up to 20 µmoles, as shown in Figure 1. These cartridges may also be used in a pre-purification step before proceeding to HPLC purification. The injection of such a pre-purified product usually results in better separation, as a higher concentration of full-length product is injected on the preparative HPLC column. Assuming the DMT is removed during Glen-Pak processing, the second purification step would ideally be ion-exchange purification, but the option to elute the product DMT-ON is also available if second step RP-HPLC is more desirable.

The Glen-Pak 3g cartridge utilizes the same reagent set and basic protocol as the standard Glen-Pak cartridge but with a 10 fold linear increase in volume for each step. A full protocol for use, including suggestions for oligonucleotide work up, is located in the latest version of the Glen-Pak purification booklet on our website: http://www.glenresearch.com/Technical/GlenPak_User_Guide.pdf

FIGURE 1: IEX HPLC of 20 MIcromole synthesis purified on Glen-Pak 3g - crude and purified

IEX HPLC Column: Dionex DNAPac PA200 250 x 4mm Buffers: A - 25mM Tris, pH 8, 5% ACN; B - 25mM Tris, pH 8, 5% ACN, 1.0M NH4Cl, pH 8 Gradient: 0-90% Buffer B at a flow rate of 1mL/min.

Glen-Pak™ 30mg 96-Well Plates:

The Glen-Pak DNA 30mg 96-well plate is designed for those customers looking for true high throughput, small scale, DMT-ON purification of oligos via either a stand-alone manifold or with their currently installed SPE robotics-based vacuum systems. Each well in the standardized 96-well filter plate is filled with 30mg of Glen-Pak DNA purification resin, which is enough to purify up to a 50 nmole scale synthesis, as shown in Figure 2.

For stand-alone use, the 96-well plate can be coupled to a vacuum source, a collar-based manifold and a waste tray for loading or rinse steps. The standard sample load and rinse volumes are 500 µL with final elution volumes of 250 µL, which are collected into a 96-well deep well plate. These volumes are only suggestions based on our experience and could be lower with specific methods development. The plate is also compatible with previously installed 96-well filter plate and SPE manifold systems.

The advantages of using the 96-well format include:

• Lower cost processing (less labor and unattended operation if using a robot).
• Less processing time per oligo when using a whole plate.
• Less solvent usage for every purification step.
• Less final elution volume to dry in preparation for analysis or use.
• Both products offer the same benefits that are expected from the standard Glen-Pak DNA Cartridges:
• No need to dry down a deprotected oligo prior to purification.
• High affinity for DMT-ON fragments.
• Lack of length restrictions that usually hamper more classical SPE purification methods.

FIGURE 2: RP HPLC of 50 Nanomole synthesis purified on Glen-Pak 96-well plate - crude and purified

RP HPLC Column: Waters Spherisorb 5.0µm ODS2 4.6 x 150mm Buffers: A – 100% Acetonitrile; B – 0.1M TEAA; Gradient: 3-40% Buffer A at a flow rate of 1mL/min.