YMC Analytical Columns: YMC-Pack J'Sphere ODS

General

The demand for higher resolution and enhanced selectivity in modern HPLC analysis has a strong impact on the development of novel HPLC packings and stationary phases. For these reasons, YMC created a series of novel packing materials, namely J'sphere ODS series, with graduated properties with respect to hydrophobicity and hydrogen bonding (H-bonding) capacity to meet the needs for sophisticated HPLC methods. 

Physico-Chemical Properties

J’sphere ODS packings are based on a spherical, ultra pure, high surface area silica with a mean pore diameter of 80 Å and a mean particle diameter of 4 µm.
J’sphere silica has a very homogeneous surface providing additional siloxane groups. These are almost of the same as ether groups and they are able to form H-bonding which is of great importance for the retentivity and selectivity of J’sphere ODS bonded phases.

Graduated Properties 

Alkyl chains of various length, such as C18, C8 and C4 for example, are commonly used for bonding during the synthesis of reversed phase materials of different polarity. YMC however, applies another approach for creating divergent polarities and improving the consistency in the synthesis of reversed phase packings. YMC keeps the C18-alkyl chain length constant, but specifically changes content of C18 groups at the silica surface, yielding three different J´sphere ODS packings with graduated hydrophobicity (fig. 1).  

Selectivity Data 
The exclusive use of C18 groups makes the hydrophobic interaction identical for all three types of J´sphere ODS packings; only the degree of hydrohobicity, i.e. the polarity, is varied. 

In addition to the hydrophobic interaction, the surface siloxane groups of J’sphere ODS packings
provide a pronounced H-bonding capacity contributing additional selectivity. The ability to interact
strongly via H-bonding creates the opportunity to make use of an additional degree of freedom in
selectivity. The “controlled hydrogen bonding capacity" of YMC J’sphere ODS packings represents
an efficient tool for the chromatographic discrimination of closely related compounds presenting
only minor molecular differences.

Conclusion
By using the graduated properties of J’sphere ODS columns, a great variety of chemical and pharmaceutical applications can be achieved. YMC J’sphere ODS analytical columns are a good choice for the analysis of pharmaceuticals, organic intermediates, metabolites etc., due to their concept of fine-tuned approach by using different H-bonding capacities.

Quality Specifications
Based on the experience in high performance analytical selectivities and large scale silicas synthesis and bonded phases, the long term availability of high quality analytical J’sphere ODS columns is guaranteed. Sophisticated selectivity tests for quality control ensure reproducible separations.
These quality control tests guarantee the customer long term reproducible performance, which is
essential for the validated analytical HPLC methods.

Column care
The recommended pH range of using YMC J’sphere ODS-M80 and -L80 columns is pH 2-7.5 and pH 1-9 for J’sphere ODS-H80. Remove acid and buffer salts before storage. Store the column in methanol/water = 50/50. Clogged inlet frits often can be cleaned by changing the flow direction or replacement.
For detailed information please refer to the “Column Care and Use Instructions”, which are shipped with each analytical column