Introduction

• Strategy
  (Acrobat pdf 7KB)
• Highly Sulfated  Cyclodextrins
• Alphabetical by drug
  (Acrobat pdf 343KB)
• Neutral compounds
  (Acrobat pdf 135KB)
• Basic compounds
  (Acrobat pdf 158KB)
• Zwitterions
  (Acrobat pdf 57KB)
• Amino acids
  (Acrobat pdf 123KB)

Free CD-ROM tutorial

Instrumentation

The Cure for Chiral Headaches

Separation of Amphetamine Enantiomers

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Since the colligative properties of chiral enantiomers are identical, typical measurements and separation techniques cannot be used to identify one from the other. The key to separating enantiomers is to first create diastereomers from these enantiomers. Diastereomers may be created through chemical derivatization with a "chiral" reagent, or they may be formed transiently through interactions with chiral selectors. The latter of course is usually the most desirable as it is the easiest to employ. These chiral selectors have historically been introduced in the form of chromatographic media using HPLC, SFC or GC as the separation technique. Although chromatography has been a very effective methodology for chiral separations, the process of developing the methodology tends to be very expensive as development time is long, column lifetimes are short and costs of chiral reagents are prohibitively high. Sometimes of course the task may seem insurmountable.

Capillary electrophoresis has proven the most ideal analytical tool for this purpose, as it is simple to construct and modify a chiral environment within a capillary. The use of cyclodextrins for differential host-guest complexation of enantiomers is by far the most common "solution-based" chiral selector and is the basis of the chiral separation strategy that we propose.  Beckman Coulter's primary strategy focuses on the use of highly sulfated cyclodextrins (HSCDs), which are a family of three chiral reagents. This strategy first involves screening the compound for separation using all three (a b and g) HSCD's and then optimizing on the reagent, which yields the best resolution. This initial screen involves the use of a single method and has been successful in greater than 97% of the compounds that Beckman Coulter has analysed.

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Highly Sulfated Cyclodextrins

The HSCDs are a proprietary distribution of cyclodextrins with an average number of 12 sulfates for the b-CD, 11 for the a-CD and 13 for the g-CD. This distribution was "designed in" to provide increased resolution under defined separation conditions. These products perform well for the analysis of many neutral, basic and weakly acidic compounds of pharmaceutical and biological interest. To ensure batch to batch consistency we have developed a process which generates the final product as a 20% w/v solution of the HSCDs. Our processes in combination with a very rigorous quality control program ensure consistent matching of all lots to a Gold Standard.

149869 Highly Sulfated Cyclodextrin Trial Kit (consists of):

• HS a Cyclodextrin (5mL) 20% w/v
• HS b Cyclodextrin (5mL) 20% w/v
• HS g Cyclodextrin (5mL) 20% w/v
• HS Cyclodextrin Test Mix
• PTS Marker (1 mL @ 10mMolar)
• Capillary Conditioning Solution and Phosphate Buffer, pH 2.5 (50mL)

713348 HS a Cyclodextrin (5mL) 20% w/v
713349 HS a Cyclodextrin (100mL) 20% w/v
713331 HS b Cyclodextrin (5mL) 20% w/v
713347 HS b Cyclodextrin (100mL) 20% w/v
713350 HS g Cyclodextrin (5mL) 20% w/v
713351 HS g Cyclodextrin (100mL) 20% w/v
713330 HS Cyclodextrin Test Mix
713328 PTS Marker (1 mL @ 10mMolar)
713333 Capillary Conditioning Solution (10mL)
477422 Phosphate Buffer, pH 2.5 (50mL)

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