Chiral e-Times 2010 Volume 1


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  1. Calling All Chiral Chromatographers: Participate in New CSP Developments!
  2. Web Focus: Chiral Chromatography Resources
  3. Application Focus: Enantiomers of Amphetamine and Methamphetamine
  4. Kromasil® Chiral Phases (CelluCoat™, AmyCoat™, DMB and TMB) from Supelco
  5. Chiral Services Update: Newly-expanded Chiral Screening Services
  6. Partner Update: Aldrich ChemFiles, New Format
  7. Tips and Tricks: Quick Regeneration of CHIROBIOTIC Columns; When to Add Water to Mobile Phases
  8. Seminar & Tradeshow Update: Innovations in Chromatography & Sample Prep; ASMS, HPLC, etc.
  9. New Literature: Brochure on Sample Prep for Chiral LC-MS
  10. Special Offer: Kromasil Chiral Columns

1. Calling All Chiral Chromatographers: Participate in New CSP Developments! back to top

Get involved in the development of new CSPs by becoming part of our beta-test community. Customer input early in the development process is an integral part of successful product design. If you screen chiral columns and are looking for phases with different selectivity or other performance variables, we would like to include you in our development efforts for new CSPs. You have the opportunity to give feedback early in the development process, and be at the forefront to publish and present your results.

If you are interested in becoming part of our beta-test community, please send an email to tracy.ascah@sial.com. Put “beta-test” in the subject line. I hope to hear from you!


2. Web Focus: Chiral Chromatography Resources back to top

Our technical resources to assist our customers who perform chiral separations are continually updated and focused under one convenient URL: sigmaaldrich.com/chiral-chromatography.

Applications: A growing list of hundreds of enantiomer separations is available on our web site. You can either browse through the chiral applications in the online catalog; or, just type in the compound of interest within the search box from any page within our site, then look under the ‘Applications’ tab of the search results. You can view the application chromatogram, conditions and all related products (standards, columns, etc.).

Bibliography: Our chiral bibliography is accessed through the Learning Center of the chiral chromatography page. Here we have compiled over 600 citations relating to our chiral HPLC and GC columns published in refereed journals. The references have been organized by phase and by analyte class. There are also purely mechanistic papers, as well as papers published by Prof. Daniel Armstrong – the inventor of Astec CYCLOBOND and CHIROBIOTIC phases.

Technical literature, handbooks and presentations: Through the Learning Center, you can access technical literature and method development information to help you find and use a chiral column.


3. Application Focus: Enantiomers of Amphetamine and Methamphetamine back to top

The CNS stimulants amphetamine and methamphetamine are among the most widely used and abused pharmaceutical substances. They are also chiral compounds. Like most bioactive compounds, the enantiomers exhibit different biological activity. They are also basic and polar, which makes analysis by most chiral stationary phases difficult. We have developed a reliable, simultaneous separation of d- and l- forms of amphetamine and methamphetamine. The separation uses a macrocyclic glycopeptide-based CSP, Astec CHIROBIOTIC V2, and a simple mobile phase of methanol containing volatile salts. The vancomycin molecule that comprises the stationary phase (CHIROBIOTIC V2) possesses ionic groups that are integral for enantioselectivity. This is an important feature, unique to CHIROBIOTIC phases. The ratio of the acid and base in the mobile phase is adjusted to control ionization and retention. In this separation, a 1:1 ratio of acid:base was used. The mobile phase also provides good MS-compatibility. Should enhanced sensitivity be desired, 2.1 mm or 1 mm I.D. columns could be used. (View this application)


4. Kromasil Chiral Phases (CelluCoat, AmyCoat, DMB and TMB) from Supelco back to top

(Please see our limited-time, special offer on Kromasil Chiral Columns)
Supelco is now the sole distributor of Kromasil products in USA, Puerto Rico and Canada. This relationship gives us access to the highly regarded Kromasil chiral HPLC line. Developed for analytical to process scale liquid chromatography, there are currently four members of the Kromasil chiral family:

Kromasil AmyCoat and CelluCoat: The functionalized amylose and cellulose chiral selectors are coated onto a super-wide pore silica (> 1000 Å) matrix. This silica has a low surface area, which reduces the number of achiral interaction sites and thus increases the chiral selectivity. High resolution, excellent selectivity, high-pressure stability, and stable performance when switching between compatible mobile phases are some important benefits.

  • AmyCoat: The chiral selector is tris-(3,5-dimethylphenyl)carbamoyl amylose.
  • CelluCoat: The chiral selector is tris-(3,5-dimethylphenyl)carbamoyl cellulose.

Kromasil DMB and TBB: These bonded chiral phases separate a broad range of racemates and complement each other in selectivity. The chiral monomers are polymerized with a hydrosilane to yield a network polymer, which incorporates the bifunctional C2-symmetric chiral selector and is covalently bonded onto 100 Å silica.

  • Chiral DMB: The chiral monomer is O,O'-bis (3,5-dimethylbenzoyl)-N,N'-diallyl-L-tartar diamide.
  • Chiral TBB: The chiral monomer is O,O'-bis (4-tert-butylbenzoyl)-N,N'-diallyl-L-tartar diamide.

We also offer a Kromasil chiral column test kit (K08971081) that includes one each of the above four Kromasil columns. Click here to view our chiral column test kits that also include CHIROBIOTIC and CYCLOBOND phases. The complete Kromasil offering can be found at sigma-aldrich.com/kromasil.

Please see our limited-time, special offer on Kromasil Chiral Columns in this newsletter.


5. Chiral Services Update: Newly-expanded Chiral Screening Services back to top

With the addition of normal phase screening and purification, Supelco is distinct in offering chiral separation products, chiral method development and chiral purification services that cover a wide range of analyte types (including highly-polar compounds), separation modes, solvent systems, and assay requirements. Our comprehensive screening package is intended to assist customers in their method development efforts, no matter what the needs of the assay are.

Our semi-automated HPLC chiral screening protocol includes a combination of 12 different stationary phases and 6 different elution systems. The highly effective protocol includes normal-phase, polar organic, polar ionic, and reversed-phase modes of elution. Stationary phases range from cellulosic/amylosic chemistries to the more polar CHIROBIOTIC phases, each exhibiting unique separation qualities for a wide range of analyte structures. We offer detection by UV, ELSD, fluorescence, refractive index and mass spectrometry.

The GC protocol involves the manual exploration of at least three selected chiral columns and employs a thermal gradient. Once the stationary phase chemistry has been identified, an isothermal system is generated to further optimize the separation. Mass spectrometry detection is used to confirm derivatization, if needed.

Output is provided in the form of a full report including acquired data, spectral analysis (if performed) and recommendations.

Stationary phase screening is a necessary and integral part of chiral method development. Data obtained from the screening protocols provide a comprehensive picture of the possible solutions. Methods intended for analytical separations as well as preparative efforts can be derived from this screening data.

Example of Report from Supelco Chiral Services

In short, Sigma-Aldrich/Supelco offers comprehensive HPLC and GC screening services. At a cost of less than the price of a single analytical column, employment of the program makes sound financial sense.

To learn more about our Chiral Services, please visit www.sigma-aldrich.com/chiral_services


6. Partner Update: Aldrich ChemFiles, New Format back to top

ChemFiles provides a forum to highlight the latest products and services from Aldrich Chemistry for the advancement of chemical research. The primary focus areas are Building Blocks, Catalysis and Inorganic Reagents, Chemical Biology, Organometallic Reagents, Specialty Synthesis, Synthetic Reagents, Stockroom Reagents, Labware, Chemistry Services and – especially relevant to Chiral eTimes readers – Asymmetric Synthesis. In contrast to earlier versions where a single issue was dedicated to a specific topic, from now on all of the Aldrich Chemistry products, including those for asymmetric synthesis, will be included in every issue. This means a quarterly update on what is going on in Aldrich’s Chemistry innovations.

ChemFiles Volume 9, No. 2Pertinent to this eNewsletter, the edition ChemFiles, Vol. 9, No. 2  includes asymmetric synthesis topics – including asymmetric epoxidation of allylic alcohols, asymmetric epoxidation of homoallylic alcohols, asymmetric transfer hydrogenation, and asymmetric ketone hydrogenation.

View and subscribe to ChemFiles by visiting sigma-aldrich.com/chemfiles.

7. Tips and Tricks: Quick Regeneration of CHIROBIOTIC Columns; When to Add Water to Mobile Phases back to top

The ionic functional groups present in CHIROBIOTIC phases means you can use polar additives (salts, water) to improve method development, method reproducibility and column performance.

Quick regeneration of Astec CHIROBIOTIC columns:
To keep your columns in top performance and maximize lifetime and method reproducibility during operation, macrocyclic antibiotic-based Astec CHIROBIOTIC columns should be cleaned once a week with 20 column volumes of a 1:1 acetonitrile:50mM ammonium acetate mobile phase, followed by 20 column volumes of 100% methanol. Before storing the column, we recommend that you run a quick QA test using 5-methyl-5-phenylhydantoin (40095-U) with methanol as the mobile phase. Refer to the QA test report that is included with the column for full details.

Addition of small amounts of water to POM (PIM) - when to do this.
When developing a method for ionizable analytes (acids, bases, zwitterions) on Astec CHIROBIOTIC columns, the polar ionic mode (PIM) is a good starting point. The polar ionic mode mobile phase is methanol containing 0.1% w/v ammonium formate. Vary the NH4OH:formic acid ratio, or try other ammonium salts (e.g. trifluoroacetate or acetate) for optimization. In LC-MS applications, a small amount of water (3-5%) can be added to the mobile phase to improve sensitivity and reproducibility of the method. The addition of water helps to improve the solubility of salts in the methanol.


8. Seminar & Tradeshow Update: Innovations in Chromatography & Sample Prep; ASMS, HPLC, etc. back to top

Innovations in Chromatography & Sample Prep - Seminars
In recognition of 2010 as the Year of Education in Separation Science, Supelco is presenting chromatography and sample prep seminars at various locations within the US and Canada over the year. These seminars describe the fundamental principles of chromatography and position recent product innovations within the context of these principles. The seminars are being presented by Supelco R&D chemists and invited guest speakers from academia and industry. Complete details and registration instructions can be found at www.sigma-aldrich.com/analytical-seminars.

Regional Tradeshows and Chromatography Discussion Groups
Supelco participates in many tradeshows throughout the year, across many industries and around the globe. Take the time to visit our dedicated tradeshows web page to see where you can find us. Some upcoming shows we will be attending:

  • Triangle Chromatography Symposium (May 20)
  • Minnesota Chromatography Forum (May 12 – 13)
  • ASMS (May 23 – 27)
  • HPLC (June 19 – 24)
  • Chirality (July 12 – 15)

9. New Literature: Brochure on Sample Prep for Chiral LC-MS back to top

Removing matrix components that suppress ionization is important to maximizing MS sensitivity. How does this relate to chiral separations? If you are looking at enantiomers in biological fluids, it is very important. We have developed a unique and very successful analytical tool to remove two major matrix components: phospholipids and proteins.

Phospholipids (PLs) are the primary constituent of cell membranes and are present in extremely high (mg/mL) concentrations in biological matrixes. PLs are a major cause of ion-suppression in mass spectrometry (MS), especially in the positive ion electrospray mode (+ESI), and, like proteins, they foul HPLC columns, shorten column life, and cause baseline drift and noise.

Supelco has developed a technology, HybridSPE-PPT, which effectively removes both proteins and phospholipids in a single method, producing samples ready for LC-MS analysis. A great deal of information about HybridSPE-PPT can be found on our web site, where you can also download new literature.


HybridSPE-PPT “In-Well” 96-well Precipitation Method and Phospholipid Removal
hybrid spe ppt

View the details for each step in this process

  1. Precipitate Proteins
  2. Mix
  3. Apply vacuum
  4. Results

10. Special Offer: Kromasil® Chiral Columns back to top

For a limited time, take 10% off Kromasil Chiral HPLC columns and kits!
Specify Promotion Code 267 to receive a 10% discount on the columns listed below.
Limit one of each part number per customer. US customers only. Offer good through May 31, 2010.
Many more Kromasil chiral column dimensions, prep, guards and bulk material, are available. Please go to  sigma-aldrich.com/kromasil.


Ordering Information
Part No. Description Regular Price Special Price Savings
Chiral HPLC Columns
K08670374 Kromasil® CelluCoat™, 25 cm x 4.6 mm I.D., 5 µm particles $1,536 $1,382 $169
K08670370 Kromasil® CelluCoat™, 15 cm x 4.6 mm I.D., 3 µm particles $1,536 $1,382 $169
K08670348 Kromasil® AmyCoat™, 25 cm x 4.6 mm I.D., 5 µm particles $1,536 $1,382 $169
K08670346 Kromasil® AmyCoat™, 15 cm x 4.6 mm I.D., 3 µm particles $1,536 $1,382 $169
K08670375 Kromasil® Chiral DMB, 25 cm x 4.6 mm I.D., 5 µm particles $1,536 $1,382 $169
K08670376 Kromasil® Chiral TBB, 25 cm x 4.6 mm I.D., 5 µm particles $1,536 $1,382 $169
Test Kit
K08971081 Kromasil® Chiral Test Kit (one each K08670370, K08670346, K08670375 and K08670376) $3,756 $3,380 $375