Page 18 - Tandem Techniques

Page xi

PREFACE

Among the plethora of investigative procedures that are available to the contemporary scientist, it is
clear that the most important and frequently used techniques are concerned with analytical chemistry.
The majority of modern analyses embody two essential parts. The first isolates the substances of
interest from the matrix of the sample, the second identifies and quantitatively estimates them. In the
past the two stages have been carried out sequentially, as separate and independent procedures.
Complex, high efficiency instruments are available to separate the components of interest from the
matrix and each other, and equally complex spectroscopic devices are available to unambiguously
identify them However, in order to cope with the high sample load experienced by many analytical
laboratories today, the speed of analysis had to be increased by combining the separating device with
the identifying spectrometer in a single tandem instrument.

The combination of two complex measuring systems must be achieved with neither instrument
degrading the performance of the other. This combination is difficult but, nevertheless, has been
successfully achieved by the use of some cleverly designed interfaces. There are many diverse
separating procedures and many different identifying instruments, and each particular combination
demands a unique interface. This book has been written to acquaint the reader with the many different
tandem systems that have been devised and the details of the interfaces with which they have been
employed. A wide range of spectroscopic techniques are discussed together with the many forms of
chromatographic and electrophoretic separating procedures with which they can be used. Application
examples of most tandem combinations are included. This book, is intended to introduce the reader to
the wide range of tandem techniques that are now available, to provide a basic understanding of their
function and operation, and to help in the selection of the appropriate instrumentation for any chosen
application.

RAYMOND P. W. SCOTT OCTOBER 1996
BIRKBECK COLLEGE, LONDON
GEORGETOWN UNIVERSITY, WASHINGTON, DC.