Synthesis of bonded phase materials

1 Stationary phase considerations. The retention mechanism(s) by which bonded phases retain solutes is complex and not fully understood [71-73]. It may be that it is comparable in behaviour and function to conventional partitioning in liquid-liquid phase systems or there may be competition between eluant and solute molecules for position on the stationary phase. It is likely that there are several mechanisms operating however it is adequate to regard the stationary phase as a conventional, physically retained liquid with which analytes interact by the conventional sorption processes. 

In reverse phase chromatography, retention times increase with increase in chain length of the bonded phase. Longer solute retention generally provides for enhanced resolution and thus varying chain length of bonded phase is a further aid to optimising the resolution. 

The percentage carbon loading is not so important a consideration as is the percentage coverage of the silica. The degree of surface coverage greatly 

Packing material Phase Particle shape and size (pm) Pore size (A) Pore volume (ml g ) 

Packing material Phase Particle shape and size (pm) Pore size (A) Pore volume (ml g ) Surface area (m g- ) Carbon load (%) Bonded phase coverage (pmolm ) End capping 

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