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Chiral e-Times 2009 Volume 1


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  1. New chiral chromatography resources on the web
  2. Fast chiral LC-MS methods
  3. Unique selectivity of CYCLOBOND I 2000 DNP
  4. Updated LC-MS capabilities in our Chiral Services Laboratory
  5. Tradeshow Update - Pittcon, EAS and Chirality
  6. Tips and Tricks – Improving the ruggedness and repeatability of polar ionic methods
  7. Special Offers

1. New chiral chromatography resources on the web back to top

Developing a new chiral method typically involves perusing application databases, consulting the literature, screening columns or contracting with a chiral service lab. Supelco can help with all of these approaches.

Centralized location of chiral products, resources, services – via the new Chiral Chromatography portal
Visit www.sigmaaldrich.com/chiral-chromatography

“Chiral Chromatography” has been added to the left navigation bar for quick access to this page from any web topic under Analytical/Chromatography.
LC-MS screening protocol.


5. Tradeshow Update - Pittcon, EAS and Chirality back to top

Recent PittCon and EAS presentations

View all our chiral presentations, including those from PittCon-2009 and EAS-2008, using the Presentations link under the Learning Center of our chiral chromatography portal.

Chirality 2009 (July 12 - 15, 2009, Breckenridge, CO)

At this tradeshow, Supelco will offer three presentations:
"Significant Improvements in Chiral Method Development using an LC-MS-Based Screening Approach"
"Performance and benefits of macrocyclic glycopeptide-based CSPs in enantiomeric purification using bench-top simulated moving bed (SMB) technology"
"Effects of pi-base/pi-acid derivative chemistry on enantioselectivity of chiral stationary phases"

And one vendor seminar:
“Strategies for Chiral HPLC Method Development”

If you are interested in registering for the vendor seminar, please send an email to tracy.ascah@sial.com

To see our complete tradeshow schedule for 2009, visit www.sigmaaldrich.com/analytical-events


6. Tips and Tricks – Improving the ruggedness and repeatability of polar ionic methods back to top

Resolution of polar and ionic enantiomers is a unique and valuable feature of Astec CHIROBIOTIC CSPs. The mobile phases for these separations are quite simple: polar organic solvents, such as methanol or acetonitrile, containing volatile acids and bases or their corresponding salts. The concentrations of the acid and base or the acid:base ratio are varied to optimize retention and selectivity.

However, retention time variation and slow equilibration may occur when these additives are employed at high concentrations or when the solubility of the additive in the solvent is limited. We have found that the addition of a small amount of water to the mobile phase increases the additive’s solubility, reduces equilibration time and improves the stability of retention times if needed. Typically, the addition of 5 to 10% v/v water to the methanol mobile phase was sufficient to provide stable retention and maintain enantioselectivity, while also maintaining the same ionic mechanism.


7. Special Offers back to top

For a limited time --
30% off Astec CYCLOBOND I 2000 DNP

If you routinely screen chiral HPLC columns, or if your enantiomers possess pi-electron systems, then Astec CYCLOBOND I 2000 DNP should be in your toolkit.
This ß-cyclodextrin derivative has unique enantioselectivity toward compounds have pi-electron systems (e.g. aromatic rings, carbonyl groups) in the stereogenic environment. It also has the benefit of operating in familiar reversed-phase mobile phases.

Ordering Information
Part No. Description
25018AST Astec CYCLOBOND I 2000 DNP, 10 cm x 2.1 mm I.D., 5 µm particles
25019AST Astec CYCLOBOND I 2000 DNP, 15 cm x 2.1 mm I.D., 5 µm particles
25020AST Astec CYCLOBOND I 2000 DNP, 25 cm x 2.1 mm I.D., 5 µm particles
25021AST Astec CYCLOBOND I 2000 DNP, 5 cm x 4.6 mm I.D., 5 µm particles
25022AST Astec CYCLOBOND I 2000 DNP, 10 cm x 4.6 mm I.D., 5 µm particles
25023AST Astec CYCLOBOND I 2000 DNP, 15 cm x 4.6 mm I.D., 5 µm particles
25024AST Astec CYCLOBOND I 2000 DNP, 25 cm x 4.6 mm I.D., 5 µm particles
25034AST Astec CYCLOBOND I 2000 DNP, 25 cm x 10.0 mm I.D., 5 µm particles
25100AST Astec CYCLOBOND I 2000 DNP, guard cartridge, 2 cm x 4.0 mm I.D., 5 µm particles
(requires holder, 21150AST, sold separately)
25101AST Astec CYCLOBOND I 2000 DNP, guard 2 cm x 1.0 mm I.D., 5 µm particles

Specify Promotion Code 960 to receive a 30% discount on any CYCLOBOND column listed above.
Offer good through June 30, 2009.