Products

COSMOSIL Cholester

Features

Column Image

  • Cholesterol bonded stationary phase
  • Usable under condition the same as C18
  • Increased stereoselectivity and improved resolution for geometric isomers
  • For separation of natural compounds

For information on COSMOCORE 2.6Cholester (2.6 µm Core Shell Particle)

Product Information

Column Specifications

Column Specifications

Hydrophobic Interaction

Figure shows the comparison of hydrophobic interactions with competitive C18 columns. Cholester provides the same hydrophobicity as alkyl group bonded types (C18, C30). It is not necessary to change the analytical conditions when replacing C18 or C30 columns with Cholester.

Chromatogram

Condition
Mobile phase Methanol/H2O = 80/20 Sample 
  1. Benzene (1.67μg)
  2. Toluene (1.67μg)
  3. Ethylbenzene (1.67μg)
  4. n-Propylbenzene (1.67μg)
  5. n-Butylbenzene (1.67μg)
  6. Amylbenzene (1.67μg)
Flow rate 1.0ml/min
Temperature 30°C
Detection UV 254 nm

Comparison of Molecular Shape Selectivity

The stationary phase of Cholester has very rigid structures and can distinguish different molecular shapes. Cholester offers improved separation for structurally similar compounds that are difficult to analyze with alkyl group bonded materials (C18 and C30). As in the following example Cholester retains planar Triphenylene longer than stereoscopic o-Terphenyl.

Figure. Comparison of molecular sharp selectivity

Comparison_of_molecular_charp_selectivity

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Molecular_shape_selectivity_data

Condition
Column Size 4.6 mm I.D. x 150 mm
Mobile phase Methanol : Water = 90 : 10
Flow rate 1.0 ml/min
Temperature 30 °C
Detection UV 254 nm
Sample 1. o-Terphenyl 0.10 µg
2. Triphenylene 0.01 µg

Improvement in Separation

COSMOSIL Cholester provides enhanced selectivity over traditional C18 columns and offers greater performance in separating isomers or other closely related compounds. COSMOSIL Cholester is ideal for method development and serves as an excellent alternative to traditional C18 columns. The figure below shows analytical data of chloroacetophenone isomers. These isomers are difficult to separate with C18 and C30, but they are well resolved by COSMOSIL Cholester.

Improvement-in-separation

Efficiency of Preparative Separation

The figure below shows the comparison of efficiency of preparative separation with a C18 column. Both columns show good separation. However, sample loading capacity for preparative separations can be affected by a slight difference in separation ability. COSMOSIL Cholester can load 4 times of sample volume compared with C18 columns.

Efficiency-of-preparative-s

Condition
Column Size 4.6 mm I.D. x 150 mm Detection UV 254 nm
Mobile phase Methanol : Water = 100 : 0 Sample
  1. Bibenzyl
  2. Anthracene
Flow rate 1.0ml/min
Temperature 30°C

Applications

Catechins

Condition
Column Size 4. 6mm I.D. x 150 mm Sample
  1. (-)‐Gallocatechin [(-)‐GC](0.80mg/ml)
  2. Caffeine (0.08mg/ml)
  3. (-)‐Epigallocatechin [(-)‐EGC](0.80mg/ml)
  4. (-)‐Catechin [(-)‐C](0.40mg/ml)
  5. (-)‐Epicatechin [(-)‐EC](0.40mg/ml)
  6. (-)‐Epigallocatechin Gallate [(-)‐EGCg](0 20mg/ml)
  7. (-)‐Gallocatechin Gallate [(-)‐GCg](0.40mg/ml)
  8. (-)‐Epicatechin Gallate [(-)‐ECg](0.20mg/ml)
  9. (-)‐Catechin Gallate [(-)‐Cg](0.20mg/ml)

Injection Vol. 1.0μl

Mobile Phase A: Acetonitrile/ 20mmol/l Phosphate buffer(pH2.5) = 10/90
B: Acetonitrile/ 20mmol/l Phosphate buffer(pH2 5) = 30/70
B conc. 0→100% 20min Linear gradient
Flow Rate 1.0 ml/min
Temperature 30°C
Detection UV280nm

Flavones

Condition
Column Size 4. 6mm I.D. x 150 mm Sample
  1. Fisetin (0.25μg)
  2. Myricetin (0.20μg)
  3. 7,8-Dihydroxyflavone (0.05μg)
  4. Luteolin (0 20μg)
  5. Quercetin (0.20μg)
  6. 7-Hydroxyflavone (0.10μg)
  7. Baicalein (0.05μg)
  8. 6-Hydroxyflavone (0.05μg)
  9. Flavone (0.05μg)
  10. Chrysin (0.05μg)
  11. 6-Methoxyflavone (0.05μg)
  12. 3-Hydroxyflavone (0.25μg)
  13. 5-Hydroxyflavone (0.05μg)
Mobile Phase A: Acetonitrile/ 20mmol/l Phosphate buffer(pH2 5) = 20/80
B: Acetonitrile/ 20mmol/l Phosphate buffer(pH2.5) = 70/30
B conc. 0→100% 20min Linear gradient
Flow Rate 1.0 ml/min
Temperature 30°C
Detection UV280nm

See more COSMOSIL Applications

Usage information

Column 5 µm Cholester
I.D. (mm) 2.0 3.0 4.6 10.0 20.0 28.0
Washing method 1. Remove buffer, salts and/or acid from column: wash for 10-15 min. using the mobile phase last used, without buffer, salts or acid. For example, if your mobile phase was 50:50 methanol/20 mmol/l phosphate buffer, wash with 50:50 methanol/water.

2. (If you used a buffer, always do step 1 first!) Remove adsorbed compounds and fix unstable baselines by washing with methanol and/or THF.
Storage conditions Short-term (up to a week):
Remove buffer, salts and/or acid from column: wash for 10-15 min. using the mobile phase last used, without buffer, salts or acid. For example, if your mobile phase was 50:50 methanol/20 mmol/l phosphate buffer, wash with 50:50 methanol/water.

Long-term:
Remove buffer, salts and/or acid from column: wash for 10-15 min. using the mobile phase last used, without buffer, salts or acid. Then, replace the solvent with 70% methanol or acetonitrile : 30% water.

In either case, tightly plug the column, and store in a cool and dry place.
Usable pH range pH2~pH7.5
Max. pressure 20MPa 15MPa
Temperature range The maximum usable temperature is 60°C. However. for regular use, please use at a constant temperature between 20°C and 50°C.
Usable solvents Any solvent that will not dissolve the silica gel (such as alkaline solutions) or cleave the stationary phase (such as very acidic solutions) is usable.
Note: For solvents with high viscosity, please watch the system pressure and keep it below 20 MPa. Also, please wash the column after using acidic mobile phases or solvents with high freezing points.
Other instructions - Buffer concentration is usually sufficient at 0.005 - 0.02 mol/L.
- Always filter mobile phases using a 0.5 µm or finer filter before use.

Downloads

Brochures

  • COSMOSIL Cholester pdf (640 KB)
  • COSMOSIL 2.5Cholester pdf (1.2 MB)
  • Analysis of Natural Compounds by 2.5Cholesterpdf (390 KB)
  • Analysis of New Antimycotic Substances (5aTHQs) by COSMOSIL Cholester pdf (1 MB)
  • COSMOSIL/COSMOCORE Cholester Series Application Notebook and Reference List pdf (14 MB)

Posters

  • Identifying Vitamin D2 and D3 and their 25-OH Metabolites and C3 Epimers in a Single LC-MS Run (Poster from Food Science 2016, Singapore)
    pdf (0.2 MB)
  • Simultaneous Separation of Fat-Soluble Vitamins by Reversed-Phase HPLC Using a Cholesteryl Group Bonded Stationary Phase (Poster from AOAC Annual Meeting & Exposition 2013, Chicago, IL USA)
    pdf (0.2 MB)
  • Rapid HPLC Method Development with C18 and Phenyl Columns
    (Poster from HPLC2013, Amsterdam, the Netherlands)
    pdf (0.2 MB)
  • Simultaneous Separation of Fat-Soluble Vitamins by Reversed-Phase HPLC Using a Cholesteryl Group Bonded Stationary Phase
    (Poster from AOAC Annual Meeting 2012, Las Vegas, Nevada USA)
    pdf (0.2 MB)

References

Reference list

Ordering Information

Analytical Column (Particle Size : 5 µm)
COSMOSIL Cholester

Product Name Size Product No. Price
COSMOSIL Cholester Guard Column
4.6 mm I.D. x 10 mm 05975-71 e-Nacalai
10 mm I.D. x 20 mm 05978-41
20 mm I.D. x 20 mm 05980-91
20 mm I.D. x 50 mm 05981-81
28 mm I.D. x 50 mm 05983-61
COSMOSIL Cholester Packed Column
1.0 mm I.D. x 150 mm 05968-71 e-Nacalai
1.0 mm I.D. x 250 mm 05969-61
2.0 mm I.D. x 150 mm 05971-11
2.0 mm I.D. x 250 mm 05972-01
3.0 mm I.D. x 150 mm 05973-91
3.0 mm I.D. x 250 mm 05974-81
4.6 mm I.D. x 50 mm 06359-21
4.6 mm I.D. x 100 mm 06591-61
4.6 mm I.D. x 150 mm 05976-61
4.6 mm I.D. x 250 mm 05977-51
10 mm I.D. x 150 mm 08011-91
10 mm I.D. x 250 mm 05979-31
20 mm I.D. x 150 mm 06088-71
20 mm I.D. x 250 mm 05982-71
28 mm I.D. x 250 mm 05985-41

Ultra-High Performance Column (Particle Size : 2.5 µm)
COSMOSIL 2.5Cholester

Product Name Size Product No. Price
COSMOSIL 2.5Cholester Packed Column
2.0 mm l.D. x 50 mm 09000-01 e-Nacalai
2.0 mm l.D. x 75 mm 09047-11
2.0 mm l.D. x 100 mm 09048-01
3.0 mm l.D. x 50 mm 09049-91
3.0 mm l.D. x 75 mm 09050-51
3.0 mm l.D. x 100 mm 09051-41

For information on COSMOSIL 2.5Cholester (Ultra-High Performance Column)

(Storage) RT: Room temperature, A: Cool and dark, R: Refrigerator, F: Freeze