C18 HPLC Analytical

C18 HPLC Analytical is available in porosities of 100Å, 150Å, 200Å, and 300Å and particle sizes of 2µm, 3µm, 5µm, and 10µm.

C18 HPLC Analytical is manufactured on Sorbtech’s Premium Pure™ Spherical Silica Gel which boasts very narrow pore and particle distributions, ensuring optimal selectivity, capacity, efficiency, low operating pressure, shorter processing time; and are therefore, the best balance between high performance and value.

Premium Pure Spherical Silica Gel is manufactured to a very high chemical purity standard (>99.99% SiO₂). Organics and trace metals content are controlled within stringent limits. Each production batch has undergone extensive quality control testing to ensure reliable lot-to-lot performance. This rigid control of chemical purity, surface area and pore size, ensure our silica will yield reproducible separation results and allow for direct scale-up without requiring time-consuming method redevelopment.

Our spherical silicas are mechanically robust and can, therefore, be repacked multiple times in either analytical or preparative scale columns.

The example below compares a C18 Silica Gel to a C18 Aqueous Silica Gel. Both phases were applied to the same base silica gel. All conditions are the same. The retention times of the C18 Aqueous are reduced due to the shielding of silanol groups on the silica surface by the endcapping reagent that introduces highly polar terminal groups. The result is shorter retention times.

The example below compares a C18 Silica Gel to a C18 Silica Gel with high endcapping. Both phases were applied to the same base silica gel. With all conditions equal, the increase of shielded silanol groups with highly non-polar terminal groups on the silica surface resulted in higher retention times.

The example below compares a C18 Aqueous Silica Gel to a C18 Aqueous II Silica Gel. Both phases were applied to the same base silica gel. With all conditions equal, the higher carbon loading resulted in higher retention times.

The example below compares a C8 Silica Gel to a C18 Aqueous Silica Gel. Both phases were applied to the same base silica gel. Even though the two adsorbents have comparable carbon loading percentages, the result was a difference in selectivity. By something as simple as changing the stationary phase while keeping all conditions the same, the end user can solve or improve chromatographic results.