kromega Select
The kromega Select range of HPLC columns use more than just another new generation of HPLC packing material. The packing material is manufactured using an entirely new process based on well established, tried and tested silica production techniques coupled with new refining technologies which ultimately leads to a superior material.Specification
The fact that high purity kromega Select packing is manufactured using well established silica engineering techniques means that a wide range of specifications are possible. As a result, the range accommodates pore sizes of 120Å and 600Å.ODS-H is the most generally applicable of the kromega Select phases, with a carbon loading of 18%, and can be used for both specialist applications involving acid and basic compounds or mixtures of both.
ODS-H is also particularly well suited to general purpose method development. Buy ODS-H Columns| ODS-H Example 1. | |
 | The absence of active silanols in kromega Select is illustrated by this standard test mixture which includes both pyridine and phenol. The lack of peak tailing clearly demonstrates the absence of metallic impurities. |
| 1. Pyridine, 2. Phenol | |
| COLUMN | kromega Select ODS-H 5µm |
| DIMENSIONS | 15cm x 4.6mm |
| MOBILE PHASE | 40:60 Acetonitrile:Water |
| TEMPERATURE | 40°C |
| FLOW RATE | 1 ml/min |
| DETECTION | UV at 254nm |
| ODS-H Example 2 | |
 | Neutral silanol groups can still occasionally cause problems with certain classes of compound. Theobromine, theophylline and caffeine are particularly prone to this effect. In kromega Select this effect is elimated by full end capping. |
| 1. Theobromine, 2. Theophylline, 3. Caffeine, 4. Phenol |
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| COLUMN | kromega Select ODS-H 5µm |
| DIMENSIONS | 15cm x 4.6mm |
| MOBILE PHASE | 25:75 Methanol:Water |
| TEMPERATURE | 30°C |
| FLOW RATE | 1 ml/min |
| DETECTION | UV at 254nm |
| ODS-H Example 3. | |
 | Many compounds such as polyphenols interact irreversibly with the active sites on silica based reversed phase materials. In the case of kromega Select ODS-H this problem does not occur, which makes it possible to analyse problematic compounds such as in the ODS-H Example below. |
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| COLUMN | kromega Select ODS-H 5µm |
| DIMENSIONS | 15cm x 4.6mm |
| MOBILE PHASE | THF:Water:Formic Acid (35:60:5) |
| TEMPERATURE | 40°C |
| FLOW RATE | 0.65 Sl/min |
| DETECTION | UV at 254nm |
ODS-L has a slightly lower carbon loading (15%) than the ODS-H and is useful for the analysis of a wide range of hydrophilic compounds which are normally not retained by other C18 based packing material.
kromega Select ODS-L is also as useful for analyzing hydrophobic samples which are currently chromatographed on competitor C8 materials. Like ODS-H, this packing material is also fully end-capped. ODS-L is also based on the same high purity silica as the kromega Select ODS-H material which ensures the high degree of inertness and lack of peak tailing. Buy ODS-L Columns| ODS-L Example 1. | |
 | One particular advantage is that even pure water can be used as the eluent without the need for any organic modifier. Highly polar samples only soluble in water may be separated by this packing material, e.g. sugars and other saccharides. |
| 1. Pyridine, 2. Phenol | |
| COLUMN | kromega Select ODS-L 5µm |
| DIMENSIONS | 15cm x 4.6mm |
| MOBILE PHASE | 100% Water (HPLC Grade) |
| TEMPERATURE | 40°C |
| FLOW RATE | 1 ml/min |
| DETECTION | Refractive Index |