COSMOSIL C18-PREP
Reversed Phased Chromatography
Particle Size, Flow Rate, and Theoretical Plate Number
Because reversed phase chromatography employs eluents of high viscosity such as methanol and water, the flow rate is lower than that of normal phase chromatography, which uses solvents of low viscosity such as hexane and ethyl acetate. In general, higher theoretical plate numbers can be obtained with lower flow rates.
Packing Material by Column Size
Column size and required amount of C18-PREP packing material
| Column I.D. (mm) | Bed height (mm) | Column volume (ml) | Amount of C18-PREP (g) |
|---|---|---|---|
| 8 | 300 | 15 | 9 |
| 500 | 25 | 15 | |
| 10 | 300 | 25 | 15 |
| 500 | 40 | 25 | |
| 20 | 300 | 95 | 55 |
| 500 | 160 | 95 | |
| 30 | 300 | 210 | 125 |
| 500 | 350 | 220 | |
| 50 | 300 | 560 | 350 |
| 500 | 980 | 600 |
Packing Method
- Use a standard open glass column, close the stopcock, pack a small amount of absorbent cotton in the bottom of the column and add solvent to approximately 1/3 of the column length.
- Add a thin layer (5 mm) of sea sand to the surface of the absorbent cotton.
- Prepare a slurry solution of the packing material (30% w/v) with solvent right before packing. (Make sure to prepare enough slurry solution to form a column bed sufficient to separate the compounds of interest.)
- Simultaneously open the stopcock and add the slurry solution to the column to form the column bed.
- After packing the column, wash the newly packed column bed with 5-10 column volumes of solvent. Allow the bed to stabilize overnight in solvent.
- Add a thin layer (5 mm) of sea sand to the top of the bed in order to prevent disturbance of the top of the column bed during sample or solvent addition.
Application Data
| Vitamin E | Natural Compounds |
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Basic Compounds
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Highly Polar Compounds
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Reproducibility and Washing Methods
Wash the COSMOSIL C18-OPN packing material with tetrahydrofuran, chloroform or other solvents to remove the impurities. This packing material has excellent reproducibility and can be used repeatedly.
“CAUTION” Do not wash with basic solvents of pH 7 or more which will dissolve the silica gel or pH 2 or less which will cleave the C18 stationary phase. Dry the packing material at 50°C or less. See end of this chapter for packing method.
Ordering Information
COSMOSIL 140C18-PREP
| Product | Cat.No. | PKG Size | Price(US$) | |
|---|---|---|---|---|
| COSMOSIL 140C18-PREP | 12063-04 | 100G | 189.00 | Buy |
| COSMOSIL 140C18-PREP | 12063-75 | 500G | 683.00 | Buy |
| COSMOSIL 140C18-PREP | 12063-91 | 1KG | 1,050.00 | Buy |