HydroBond HPLC columns from MAC-MOD Analytical are available in two unique bonding chemistries, each designed to give excellent peak shape and increased retention of polar analytes.
HydroBond AQ is a non-endcapped C8 with an ether linkage near the point of attachment to the silica surface. This ether group is sufficiently polar to allow water to penetrate and hydrate the silica surface preventing "pore de-wetting" even in 100% aqueous mobile phases. HydroBond AQ can retain highly water soluble compounds such as organic acids, water soluble vitamins and low molecular weight polar compounds without the use of ion-pairing reagents. HydroBond AQ also offers excellent hydrophobic retention due to its high surface area and high carbon loading.
HydroBond PS is available in both a C18 and C8 bonded phase. HydroBond PS columns use "polar shielding" to further deactivate the silica surface assuring excellent retention and peak shape of poorly retained basic compounds. This polar end-capping also allows water to better hydrate the silica surface. HydroBond PS is compatible with highly aqueous mobile phases and is also a good general purpose reversed phase HPLC column.
Which do I choose?
Both HydroBond AQ and HydroBond PS are designed to give increased retention of polar analytes and both can function in highly aqueous mobile phases. If your sample consists of all polar compounds that can be eluted isocratically, choose HydroBond AQ. If your sample is more complex, containing both polar and non-polar analytes, gradient elution is recommended on either HydroBond PS C18 or PS C8.