Mobile phase options
Normal Phase
YMC Chiral NEA consists of polymeric 1-naphthylethylamine bonded to a wide pore spherical silica.
The R and S columns differ in the optical rotation of the CSP; the R column being formed from R-(+)1-
naphthylethylamine and the S column from S-(-)1-naphthylethylamine. This results in the two column
types having the effect of reversing the elution order of enantiomeric pairs of compounds.
Reversed Phase
YMC-Chiral NEA columns are as well suitable for reversed phase separation of polar, water soluble
compounds particularly pharmaceutical compounds.
Recommended eluents include aqueous eluents containing organic modifiers in the range 0-100% or
aqueous buffers with pH 2.0-6.5. At the pH limits the minimum organic modifier concentration should be not less than 10%. Typical organic modifiers include acetonitrile, methanol and ethanol. Buffer concentrations
should be less than 1 mol/l and must be rinsed from the column with water/modifier solutions (80-100%
water) before storage of the column. The columns should be stored in salt-free water/modifier solutions
with a minimum 40% modifier. Used under these conditions excellent column stability will be achieved.
Mobile Phase Composition Effects
 |
| Column: |
YMC Chiral NEA (R) 250 x 4.6 mm i.d. |
Flow:
Temperature:
Detection:
Sample: |
0.8 ml/min
ambient
UV at 235 nm
1,1'-Bi-2-naphthol |
1.0 ml/min
ambient
UV at 235 nm
1,1'-Bi-2-naphthol |
1.0 ml/min
ambient
UV at 254 nm
Propanolol |
Chiral Separation Mechanism
 
- π-π interactions
- hydrogen bonding
- dipole interactions
- steric effects
|
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