Reversed Phase (ODS)
|Usable pH range||:||2.0-8.0|
The combination of ultra pure silica and unique selectivity leads to a stationary phase that fulfills the relevant requirements of HPLC users. Minimal metal content and very low concentrations of residual silanols make this an ideal phase for the analysis of basic pharmaceuticals and chelating compounds even under LC-MS conditions (e.g. separation in non-phosphate buffered systems). In addition the possibility to separate polar compounds under highly aqueous mobile phase conditions without loss in retention, plate counts and peak performance greatly enhances the versatility of Hydrosphere C18. These characteristics will allow Hydrosphere C18 to be used for a wide range of applications of compounds with polar functional groups.
- Based on highly inert, ultra pure, pH neutral silica
- "Hydrophilic" C18 surface for enhanced polar selectivity
- Extremely rigorous physical and chemical specification
- suitable for conventional reversed phase and highly aqueous application
- Pharmaceutical method development
After the operation, the column was stored overnight (about 15 hours)
Retention time of nucletic acid bases is compared before and after one night standing in 100% water. Hydrosphere C18 provides stable retention and remarkable reproducibility while conventional ODS has declining retention when we compare retention time of adenine in the initial chromatograms with that of chromatograms generated the next day.
Exceptional chromatographic behavior
The separation of polar compounds under highly aqueous mobile phase conditions is not reproducible with conventional reversed-phases materials. A proprietary derivertization procedure enables Hydrosphere C18 to be penetrated by water without losing its brushlike C18 chains. This behavior has the effect that members of this group of very polar compounds can be separated from each other with excellent peak shape and remarkable reproducibility. Typical applications where no organic modifier is required including nucleic acid bases, nucleotides, organic acids,catecholamines, vitamins, peptides, etc.
|Eluent||:||20mM KH2PO4-K2HPO4 (pH 6.9)/methanol (35/65)|
|Flow Rate||:||1.0 mL/min|
|Detection||:||UV at 220 nm|
Chromatograms of Hydrosphere C18 and conventional ODS are compared by using a test mixture containing compounds that have different properties.
The chromatograms show that Hydrosphere C18 has a different separation profile of elution sequence or retention time or resolution etc. from conventional ODS.
1. Nordihydroguaiaretic acid(NAGA)
Hydrosphere C18 allow us to shorten the analysis time by 20% compared with conventional ODS for the separation of highly hydrophobic compounds.