COSMOSIL 3C18-EB
Features
- Excellent for Basic compounds
- Suitable for Drug Analysis
Product Information
Column Specifications
Analysis of Basic Compounds
Conventionally end-capped C18 columns still have many residual silanol groups on the silica surface of stationary phase that can form ionic bonds with basic compounds. The resulting peak tailing makes accurate quantification of analytes difficult, especially in trace analyses. COSMOSIL 3C18-EB with a better end-capping treatment offers improved peak shape and separation particularly for basic compounds.
Comparison (Basic Compounds)
COSMOSIL 3C18-EB | Company A C18, 3 µm |
Company B C18, 3 µm |
Company C C18, 3 µm |
---|---|---|---|
Condition | ||||
---|---|---|---|---|
Column Size | 4.6 mm I.D. x 75 mm | |||
Mobile Phase | Acetonitrile/ 20mmol/l Phosphate Buffer(pH7.0) = 60/40 |
|||
Flow Rate | 1.0 ml/min | |||
Temperature | 40°C | |||
Detection | UV 254 nm | |||
Sample |
|
|||
Inj. Vol | 2.0 µl |
Synthesis Reproducibility
If you use insufficiently end-capped C18 columns for basic compound analyses, you may need to spend much time adjusting mobile phase conditions. You may need
- more than 3 or more organic solvents or buffers
- ion-pair reagents or additives
- buffers in different pH
In addition, the complexity of the mobile phase often is detrimental to reproducibility. COSMOSIL 3C18-EB with a new end-capping treatment allows good peak shape and separation using simple mobile phase conditions.
Analysis with Simple Condition
Complicated Condition | Simple Condition |
---|---|
Methanol/ Acetonitrile/ 20mmol/l KH2PO4, 0.2%Triethylamine(pH3.0 with H3PO4) = 35/15/50(*) | Acetonitrile/ 20mmol/l Phosphate Buffer(pH2.5) = 30/70 |
(*): USP 38(1) Amlodipine and Benazepril Hydrochloride Capsules, Performance Tests |
Condition | |||
---|---|---|---|
Column Size | 4.6 mm I.D. x 100 mm | ||
Flow Rate | 1.0 ml/min | ||
Temperature | 40°C | ||
Detection | UV 237 nm | ||
Sample |
|
||
Inj. Vol | 50 µl |
Routine Analysis
3C18-EB has excellent synthesis reproducibility and column-to-column reproducibility, so it is applicable in routine analysis such as quality control of drugs.
Excellent Synthesis Reproducibility
COSMOSIL 3C18-EB |
---|
Condition | |
---|---|
Column Size | 4.6 mm I.D. x 150 mm |
Mobile Phase | Acetonitrile / H2O = 60/40 |
Flow Rate | 1.0 ml/min |
Temperature | 40°C |
Detection | UV 254 nm |
Sample |
1. Acetophenone (0.05 mg/ml) 2. Methyl Benzoate (0.5 mg/ml) 3. Benzene (2.0 mg/ml) 4. Toluene (2.0 mg/ml) |
Inj. Vol | 1.5 µl |
COSMOSIL 3C18-EB |
---|
Condition | |
---|---|
Column Size | 4.6 mm I.D. x 150 mm |
Mobile Phase | Acetonitrile/ 20mmol/l Phosphate Buffer(pH7.0) = 60/40 |
Flow Rate | 1.0 ml/min |
Temperature | 40°C |
Detection | UV 254 nm |
Sample |
1. Amitriptylin 0.2 mg/ml 2. Propylbenzene (I.S.) 2.0 mg/ml |
Inj. Vol | 2.0 µl |
Analysis under Ammonium Acetate Buffer
COSMOSIL 3C18-EB produces sharp peaks using ammonium acetate buffer in LC-MS.
Acetonitrile/ 20mmol/l Phosphate buffer(pH7.0) = 60/40 | Acetonitrile/ 10mmol/l CH3COONH4 = 60/40 |
---|---|
Condition | ||||
---|---|---|---|---|
Column Size | 4.6 mm I.D. x 75 mm | |||
Flow Rate | 1.0 ml/min | |||
Temperature | 40°C | |||
Detection | UV 254 nm | |||
Sample |
|
|||
Inj. Vol | 1.0 µl |
Applications
Analysis of standards in USP
COSMOSIL 3C18-EB |
---|
Condition | |
---|---|
Column Size | 4.6 mm I.D. x 100 mm |
Mobile Phase | A; Acetonitrile/ 36.7mmol/l Phosphate Buffer(pH7.6) = 10/90 B; Acetonitrile/ 36.7mmol/l Phosphate Buffer(pH7.6) = 80/20 B conc. 0→ 20%(0→ 10min), 20→ 100%(10→ 30min) |
Flow Rate | 1.0 ml/min |
Temperature | 40°C |
Detection | UV302 nm |
Sample |
1. Omeprazole related compound A (0.001mg/ml) 2. Omeprazole(0.001mg/ml) |
Inj. Vol: | 20 µl |
USP 37(3) Esomeprazole Magnesium Delayed-Release Capsules, Impurities |
Usage information
Column | 3 µm 3C18-EB | |||
---|---|---|---|---|
I.D. (mm) | 1.0 | 2.0 | 3.0 | 4.6 |
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 | pH 2-10 (pH 2-7.5 recommended) | |||
Max. pressure | 30MPa | |||
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 30 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 0.45 µm or finer filter before use. |
Downloads
Brochures
- COSMOSIL 3C18-EB (1.7 MB)
Ordering Information
* Validated Columns (available in 3 different lots)
**Cartridge Holder is required.
For more information on COSMOSIL 3.0 mm I.D. columns
Other size may be available. Please enquire.
(Storage) RT: Room temperature, A: Cool and dark, R: Refrigerator, F: Freeze