The gateway to difficult separations, selectivity or efficiency? part ii

Separations Scientists are facing an increasing number of alternative HPLC Columns that are offering either orthogonal selectivity or extremely high plate numbers (efficiency) compared to those available say, 5 years ago. When faced with new separations that need to be performed, and in many cases these are getting more complex, which route do they opt to pursue at the method development stage. Much recent commercial activity has seen the promotion of ultra high efficiency columns, either by virtue of small particle sizes or use of elevated temperature (or both) as an option but we also have some unique novel chemistry, which are designed to offer alternate selectivity to the ‘traditional’ end-capped C18 (L1 designation in the US Pharmacopoeia). In the first part of the article [1] the benefits of utilising the selectivity route were discussed, here we examine the issues surrounding the ‘plate count’ route.