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µm
5 Frequently Asked Question About Lux®
Chiral Columns
phenomenex.com/Lux
GR
6796
0419
How can I reverse enantiomeric elution order?
Frequently Asked Chiral Questions
Q1:
App
ID 2
5337
OO
H3C
Cl
NH
Amylose
Batch A
0 5 10 15 20 min
mAU
0
100
200
300
400
NEW Lux i-Amylose-3
App
ID 2
5366
Cellulose
OO
CI
CI
NH
0 5 10 15 20 min
mAU
0
200
400
600
800
OO
H3C
CH3
NH
Amylose
App
ID 2
5367
0 5 10 15 20 min
mAU
0
100
200
300
400
Lux i-Amylose-1
Enantiomers of Diniconazole
Cl
Cl
H
OH
N N
N
CH3
CH3
CH3
E
S
Cl
Cl
H
OH
N N
N
CH3
CH3
CH3
E
R
Columns: Lux 5 µm i-Amylose-3Lux 5 µm i-Cellulose-5Lux 5 µm i-Amylose-1
Dimensions: 250 x 4.6 mm Part No.: 00G-4779-E0
00G-4756-E000G-4762-E0
Mobile Phase: Water with 0.1 % Diethylamine/Acetonitrile (35:65)Flow Rate: 1.0 mL/min
Injection Volume: 10 µL (2 mg/mL) Detection: UV @ 254 nm
Sample: 1. Diniconazole 2. Diniconazole
Because of the intrinsic nature of enantiomers, it is difficult to predict selectivity and therefore the relative analyte elution order. However, the Lux® polysaccharide chiral column portfolio contains a wide range of chiral stationary phases that can easily be screened for complementary or orthogonal selectivity. For instance, Lux i-Amylose-3 and i-Cellulose-5 have complementary but distinct selectivity in comparison to each other. In addition, the phase immo-bilization affords greater solvent flexibility, increasing the potential for enantioselectivity.
Lux i-Cellulose-5
Why does Phenomenex use DEA over TEA as the primary basic modifier in application notes?
Frequently Asked Chiral Questions
Q2:
Need a chiral method right now?Start your chiral method search by an analyte
name or structure search in seconds here:
www.phenomenex.com/lux
Both DEA (diethylamine) and TEA (triethylamine) are widely published as good basic modifiers for improving peak shapes on polysaccharide-type chiral columns. We chose DEA for our initial screening data and have continued with it routinely to maintain consistency. TEA is also just as effective and commonly used by many customers successfully on our Lux® polysaccharide chiral columns.
min0 2 4 6 8 10 12 14 16 18
mAU
123456789
min2 4 6 8 10 12 14 16 18
min2 4 6 8 10 12 14 16 18
App
ID 2
5342
Columns: Lux 5 µm i-Amylose-3Dimensions: 250 x 4.6 mm
Part No.: 00G-4779-E0Mobile Phase: Acetonitrile with 0.1 % Diethylamine
Flow Rate: 1.0 mL/min Injection Volume: 10 µL (2 mg/mL)
Detection: UV @ 254 nm Sample: 1. Thalidomide
2. Thalidomide
Enantiomers of Thalidomide
N
NH
O
OCH2
CH2
S N
NH
O
OCH2
CH2
R
Batch B
Batch C
Batch D
min0 2 4 6 8 10 12 14 16 18
mAU
2
4
6
8
10
12
0
min2 4 6 8 10 12 14 16 18
min2 4 6 8 10 12 14 16 18
App
ID 2
5340
Enantiomers of Econazole
Cl
O
Cl
Cl
H
N
N
S
Cl
O
Cl
Cl
H
N
N
R
Batch A
Batch B
Batch C
Columns: Lux® 5 µm i-Amylose-3Dimensions: 250 x 4.6 mm
Part No.: 00G-4779-E0Mobile Phase: Water with 5 mM Ammonium Acetate + 0.05 %
Formic Acid/Acetonitrile (65:35) Flow Rate: 1.0 mL/min
Injection Volume: 10 µL (2 mg/mL) Detection: UV @ 254 nm
Sample: 1. Econazole 2. Econazole
How does the aromaticity of chiral compounds affect selectivity?
Frequently Asked Chiral Questions
Q3: In chiral compounds, the proximity of aromatic groups to the stereocenter is typically linked to the ease of enan-tiomeric resolution. For instance, the separations of enantiomers in which the aromatic functionality is 4 or more atoms away from the stereocenter can be challenging and chromatographically uncommon. Enantioselectivity is most effective when the distances between the aromatic group and stereocenter are equivalent in both chiral conformations. If the aromatic group of the compound has electron withdrawing groups like halogens or oxygen it will be more electron deficient and will interact more effectively with electron-rich aromatic groups of the chiral stationary phase.
What is the difference between Amylose and Cellulose polysaccharide backbones?Q4:
Both backbones form 3-dimensional helical structures that are well suited to provide grooves and cavities for po-tential steric interactions, Hydrogen bonding, dipole-dipole, and π-π based interactions. However, the structure for amylose is considered more tightly coiled in comparison to the looser cellulose structure which may accommodate interactions differently. Practically, this difference can result in distinct selectivity for amylose and cellulose even if with an identical chiral selector, as the 3-dimensional orientation around the CSP will differ.
App
ID 2
5368
3
min0 5 10 15 20 25 min 35 40 45
mAU
0
10
20
30
40
50
60
App
ID 2
5369
5
min0 5 10 15 20 25 min 35 40 45
mAU
01020304050607080
mAU
App
ID 2
5370
min0 5 10 15 20 min 35 40 45
mAU
0
20
40
60
80
100
Enantiomers of Napropamide
O
CH3N
O
CH3
CH3
S
O
CH3N
O
CH3
CH3
R
Columns: Lux® 5 µm i-Amylose-3Lux 5 µm i-Cellulose-5 Lux 5 µm i-Amylose-1
Dimensions: 250 x 4.6 mm Part No.: 00G-4779-E0
00G-4756-E000G-4762-E0
Mobile Phase: Water with 5 mM Ammonium Acetate + 0.05% Formic Acid/Acetonitrile (53:47)
Flow Rate: 1.0 mL/min Injection Volume: 10 µL (2 mg/mL)
Detection: UV @ 254 nm Sample: 1. Napropamide
2. Napropamide
Frequently Asked Chiral Questions
What separation modes can Lux® polysaccharide chiral col-umns operate in?Q5:
Frequently Asked Chiral Questions
Lux chiral columns can be used in reversed phase, normal phase, polar organic, polar ionic and SFC conditions. However, the immobilization and bonding technology used within the Lux i-Amylose-3, i-Cellulose-5 and i-Amy-lose-1 columns promotes stability in strong organic solvents, which affords you the ability to expand your chiral separation success with even more solvent systems.
5µm
Column: Lux 5 µm i-Amylose-3Dimensions: 250 x 4.6 mm
Part No.: 00G-4779-E0Mobile Phase: Hexane/Isopropanol with 0.1 %
Diethylamine (80/20)Flow Rate: 0.5 mL/min
Injection Volume: 10 µL (2 mg/mL) Detection: UV @ 220 nm
Sample: 1. Trans-Stilbene Oxide 2. Trans-Stilbene Oxide
*Aggressive solvent stability was tested by flushing columns with DCM followed by THF before rerunning in the mobile phase.
Before Exposure to Strong Solvents (DCM & THF)*After Exposure
App
ID 2
5392
0 2 4 6 8 10 12 14
0
20
40
60
80
100
mAU
min
Terms and Conditions - Subject to Phenomenex Standard Terms & Conditions, which may be viewed at www.phenomenex.com/TermsAndConditions • Trademarks - Lux is a registered trademark, SecurityLINK, and SecurityGuard are trademarks of Phenomenex. • Disclaimer - Comparative separations may not be representative of all applications. SecurityGuard is patented by Phenomenex. U.S. Patent No. 6,162,362. • CAUTION: this patent only applies to the analytical-sized guard cartridge holder, and does not apply to SemiPrep, PREP or ULTRA holders, or to any cartridges. • FOR RESEARCH USE ONLY. Not for use in clinical diagnostic procedures. • © 2020 Phenomenex, Inc. All rights reserved.