VDS

VDSpher PUR and VDSpher

Classic VDSpher phases by optilab are based on two different basic silica gels: VDSpher Classic & PUR, which differ mainly in their purity. The purity of the basic silica gel has a significant impact on the chromatographic separation because the metal content changes the properties of the silica gel and the surface. Hence, the interactions between the metal parts and the electron-rich analytes need to be considered. Due to the higher metal content of the VDSpher Classic 100 C18-E phase the analytes were retarded much stronger as compared to VDSpher PUR 100 C18-E.

All VDSpher Classic & PUR silica gels are suitable for analytical, semi-preparative and preparative scale. To achieve the best possible column packing, VDSpher PUR phases are recommended for analytical issues and VDSpher Classic phases for preparative purposes.

Normally, the standard phase VDSpher PUR 100 C18-E is a good starting point for many separations, e. g. for the isolation of natural substances, for the determination of caffeine in coffee or tea and even for the determination of amino acids. VDSpher PUR 100 C18-E is of medium hydrophobicity and shows a low silanophilic activity.

VDSpher MS Phases

Columns of smaller dimensions are usually preferred in LC/MS analysis. To profit from a high resolution, silica gel with a small particle size is recommended for the column. Generally, any VDSpher column can be used for LC/MS. Mass spectrometry is a particularly sensitive detection method and displays very low impurities, e.g. carry-overs from previous runs (“carry-over effect“). VDSpher MS phases are designed specially to avoid these effects.

VDSpher OptiAqua and VDSpher OptiAqua PUR

VDSpher OptiAqua phases are ideally suited for very hydrophilic applications. A special polar endcapping makes it possible to use 100% water as a solvent while still maintaining reversed phase properties.

On the basis of VDSpher Classic & PUR, six VDSpher OptiAqua phases with different modifications as well as pore sizes and particle diameters have been developed. With these phases, numerous applications can be performed in preparative as well as analytical HPLC. Also, analytes of different sizes can be handled optimally. Thus, different molar mass ranges can be covered, depending on the pore size of the modified silica gel.

VDSpher OptiAqua phases can be used e.g. to separate polar substances. Typical analytes are antibiotics, biomolecules, drugs, nucleobases, organic acids, parabens, pesticides, sulfonamides, water-soluble vitamins and xanthines.

All VDSpher OptiAqua phases are pH-stable in a range of 2 to 7.5 and can be used without any problem up to a temperature of 60 °C.

VDSpher OptiBio and VDSpher OptiBio PUR

VDSpher OptiBio have been developed for biochemical analysis such as protein and peptide separation. Numerous separation phases with different modifications, pore sizes and particle diameters are available. With VDSpher OptiBio columns e. g. antibodies, oligo-nucleotides, peptides and proteins as well as other biomolecules can be examined.

All VDSpher OptiBio modifications are pH-stable over a large range and can be used without any problem up to a temperature of 65 °C.