Capital HPLC

Cyclodextrins

Cyclodextrins

 

These macrocyclic carbohydrate compounds
are widely used as buffer additives to obtain
chiral separations in CE. However, the can
also be used to adjust the selectivity in nonchiral
applications. There are three naturally
occurring forms, a, b and g which have 6, 7
and 8 glucose units respectively. The structure
of b-cyclodextrin is shown below. The hydroxyl
units on the top of the cyclodextrin are chirally
positioned and have different interactions with
solute enantiomers when they are included
into the cyclodextrin cavities. The hydroxyl
groups can be chemically derivatised to give
a range of neutral and ionic derivatives which
give different chiral separations and are more
water soluble that the naturally occurring forms.



Neutral cyclodextrin derivatives most
frequently used in CE are:

O- dimethyl-cyclodextrin
O- trimethyl-cyclodextrin
O- hydroxypropyl-cyclodextrin

The most commonly used ionic forms are:

O- cyclodextrin sulphonic acid
O- carboxymethyl-cyclodextrin
O- amino-cyclodextrin

Structure of b-cyclodextrin                             Schematic Representation

                                                                                                          The shape of cyclodextrins is often
                                                                                                          represented as a cone shaped cavity as
                                                                                                          shown below.


In order to obtain high efficiency separations
it is necessary that the cyclodextrins used as
CE additives are extremely pure.
Electrokinetic technologies offers a wide range
of both natural and derivatised cyclodextrins
at CE grade purity. In addition to the
cyclodextrins listed below, other derivatives
are available on request. Please contact our
sales office for details. 

 

 

Cyclodextrins (continued)

EKT Cyclodextrins

EKT has a full range of many types of
cylclodextrins too numerous to list in full.
If the cyclodextrin you require is not listed
below please contact our technical sales
office.

 
       

Cyclodextrin Starter Kit

0.1g each of a, b and g cyclodextrins
0.1g methyl-b−cylcodextrin
0.1g 2-hydroxypropyl-b−cyclodextrin
0.1g caboxymethyl-b−cyclodextrin
0.1g monoamino-b−cyclodextrin
Cat. No. EKT540             £ 275.00
 
Natural Cyclodextrins

 

Cat.No.

Description

Quantity

Price/£

EKT522

EKT523

EKT524

EKT525

EKT526

EKT527

α-cyclodextrin99%α--cyclodextrin99%β-cyclodextrin99%

β-cyclodextrin 99%γ-cyclodextrin 99%γ-cyclodextrin99%

5g

25g

5g

25g

1g

5g

 

Modified Neutral Cyclodextrins

Cat.No.

Description

Quantity

Price/ £

EKT528

EKT529

EKT530

EKT531

EKT532

EKT533

β-dimethyl cyclodextrin β-dimethyl cyclodextrin β-trimethyl cyclodextrin β-trimethylcyclodextrin

β-2-hydroxypropylcyclodextrin

β-2-hydroxypropylcyclodextrin

1g

5g

1g

5g

1g

5g

 


Ionic Modified Cyclodextrins

Cat.No.

Description

Quantity

Price/£

EKT534

EKT535

EKT536

EKT537

EKT538

EKT539

β-cyclodextrinphosphate

β-cyclodextrinphosphate

β-carboxymethyl cyclodextrin β-carboxymethyl cyclodextrin β-aminocyclodextrin

β-aminocyclodextrin

1g

2.5g

1g

5g

1g

5g