Do you know the chemistry of your stationary phase?

In this seminar, the chemistry of RP HPLC stationary phases will be unveiled. Recent history of development of advanced sorbents and bonded phases will be explained, with intention to assist in RP HPLC methods development and right choice of stationary phases.

When the question is asked, which stationary phase is used in an HPLC method, the answer is almost always:

• The manufacturers name (Agilent, Phenomenex, Thermo, Waters, YMC, etc.) and
• The phase brand name (Zorbax, Luna, Hypersil, Inertsil, Discovery, Symmetry, etc.) and sometimes
• The phase chemistry (C18, C8, CN, etc.), but usually only when the bonded phase is an alkyl silica

When the phase is anything other than a conventional alkyl silica, the fashion is to know the phase by its trade name — for example, Agilent Zorbax Bonus-RP

But what is the chemistry of this phase?

What are the mechanisms of interaction with the analyte and hence how is retention and selectivity gained from this phase?

How can we troubleshoot separation problems or develop suitable methods without a good knowledge of the bonded phase chemistry?

It’s also very important to realize that, even if the bonded phase chemistry is known, a significant contribution to retention and selectivity will be made by the underlying silica and any surface treatments which are carried out after the stationary phase is bonded

The following topics will be comprised:

• Mechanism of interaction and retention in RP HPLC
• Chemistry of silica gel
• Bonded organic phases
• Problems of silica-based stationary phases
• High purity “Type B” and “Hybrid” (organic – inorganic) silica
• Non-silica based phases
• Phases with embedded polar groups
• “Equivalent columns”? Alternative columns?