Due to their versatility and resolution, chromatographic separations of complex
mixtures of biologicals are used for many purposes in academia and industry. If
anything, recent developments in the life sciences have increased the interest
and need for chromatography be it for quality control, proteomics or the downstream
processing of the high value products of modern biotechnology. However,
the many “challenges”of present day chromatography and especially of the
HPLC of biomacromolecules such as proteins, are also present in the mind of
any practitioner. In fact, some of these latter were such hindrances that much
research was necessary in order to overcome and circumvent them. This book
introduces the reader to some of the recently proposed solutions. Capillary electrochromatography
(CEC), for example, the latest and most promising branch of
analytical chromatography, is still hindered from finding broader application by
difficulties related to something as simple as the packing of a suitable column.
The latest solutions for this but also the state of art of CEC in general are discussed
in the chapter written by Frantisek Svec. The difficulty of combining
speed, resolution and capacity when using the classical porous bead type stationary
phases has even been called the “dilemma of protein chromatography”.
Much progress has been made in this area by the advent of monolithic and related
continuous stationary phases. The complex nature of many of the samples to
be analyzed and separated in biochromatography often requires the use of some
highly specific (“affinity”) ligands. Since they can be raised in a specific manner
to many bioproducts, protein ligands such as antibodies have allowed some very
selective solutions in the past. However, they also are known to have some disadvantages,
including the immunogenicity (toxicity) of ligands contaminating
the final products, or the low stability of such ligands, which prevents repeated
usage of the expensive columns. This challenge may be overcome by “molecular
imprinting”, a techniques, which uses purely chemical means to create the
“affinity”interaction. Finally we were most happy to have two authors from
industry join us to report on their experience with chromatography as a continuous
preparative process. Readers from various fields thus will find new ideas
and approaches to typical separation problems in this volume. Finally, I would
like to thank all the authors for their contributions and their cooperation
throughout the last year.