Reversed phase Octadecyl group
Acid Resistance
COSMOSIL 5C18-AR-II packed column features a polymeric type of C18 reversed phase material. The acidic resistance of COSMOSIL 5C18-AR-II is much improved compared with commercially available monomeric type octadecyl stationary phases. It retains high performance even in case of acidic mobile phases commonly used to separate acidic compounds and peptides.
Specifications
| Packing Material | 3C18-EB | C18-MS-II | C18-AR-II | C18-PAQ |
|---|---|---|---|---|
| USP Code | L1 | L1 | L1 | L1 |
| Silica Gel | High Purity Porous Spherical Silica | |||
| Average Particle Size | 3 µm | 3, 5, 15 µm | 5, 15 µm | |
| Average Pore Size | approx. 120 Å | |||
| Specific Surface Area | approx. 300 m2/g | |||
| Stationary Phase |  |
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| Octadecyl Group | ||||
| Bonding Type | Monomeric | Polymeric | ||
| Main Interaction | Hydrophobic Interaction | |||
| End Capping Treatment | Near-perfect Treatment | |||
| Carbon Content | approx. 14.5% | approx. 16% | approx. 17% | approx. 11% |
| pH Range | 2-10* | 1.5-7.5* | 2-7.5 | |
| Feature | This phase with a better end-capping treatment offers improved peak shape and separation particularly for basic compounds. |
This phase is recommended for most applications but particularly effective for basic compounds. | This phase is recommended for separations requiring acidic mobile phase conditions. It also shows superior molecular shape selectivity to monomeric type C18columns. | This phase is designed to offer superior retention of polar compounds and excellent reproducibility in highly aqueous mobile phases, even in 100% aqueous. |
Optimum pH range of columns based on silica gel is between 2 and 7.5.
