Anal Bioanal Chem (2008) 390:1225–1226 DOI 10.1007/s00216-007-1786-x

EDITORIAL

Chemometrics in analytical chemistry Jürgen W. Einax

Published online: 10 January 2008 # Springer-Verlag 2007

Analytical chemistry is a science growing and developing at a tremendous rate. There are different main streams of development. One is the increasing use of multicomponent and multielement analytical methods. Another trend is the development and introduction of highly sophisticated new principles of instrumental analysis in routine analysis. A third topic is given by the necessity to investigate very complex problems, for example, in life sciences. Another driving force of the development in analytical chemistry is the need for fast (and cheap) analyses, which, for example, is aimed at with high-throughput analytical techniques. All these developments not only cause more information to be acquired about what we analyze but also some new inherent difficulties which we are faced with in the further treatment, evaluation, and interpretation of the analytical results obtained. Important problems which may arise are: – –

An enormous flood of data, often very badly arranged, is “produced.” The analytical data obtained—sometimes at the lower limit of efficiency of the particular analytical method used—not only contain the analytical information but also contain variability and uncertainty.

J. W. Einax (*) Lehrbereich Umweltanalytik, Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Lessingstr. 8, 07743 Jena, Germany e-mail: [email protected]

–

–

Different causes and origins influencing both the samples to be analyzed and the entire analytical process imply the multidimensional and, thus, very complex character of the analytical results. Economic limitations and practical obstacles often cause limited sample sizes and even missing values.

A powerful way to overcome these serious problems, to solve them, or, at least, to reduce their influence on the reliability of the analytical results, and to make them more objective is the application of chemometric methods. Chemometrics, according to the pragmatic definition by Massart, is the chemical discipline that uses mathematical, statistical, and other methods employing formal logic to design or select optimal measurement procedures and experiments and to provide maximum relevant chemical information by analyzing chemical data. Chemometrics is strongly connected with the development of analytical chemistry, getting impulses from it, and giving impulses back. So, chemometrics also has an impressive development in treating new mathematical and statistical principles as well as in applying itself in an increasingly broader range of very different branches of sciences, not only in analytical chemistry. In 2004 Analytical and Bioanalytical Chemistry reflected the importance of that particular development by publishing a first special issue dedicated to the problems of chemometrics at that time (Anal. Bioanal. Chem. 380:368–514, 2004). Since then interesting and important new developments in fundamentals have taken place and new fields of

1226

application have been opened. The logical consequence is to present the reader of Analytical and Bioanalytical Chemistry with a collection of current papers written by leading experts in chemometrics as a new special issue in 2008. The initial and starting point of this special issue are contributions on chemometrics from the ANAKON conference which was held in Jena on 27–30 March 2007. This collection of publications widely reflects the situation of chemometrics nowadays. There is to a smaller extent the development of the fundamentals of new methods of chemometrics, exemplified in this special issue by fuzzy clustering techniques, the test of cross-validation for multivariate statistical methods, new plans to design experiments, and considerations of the influence of the sample size on the stability of chemometric models. The dominating part of modern chemometrics is application; application in a broad range of fields, often far away from chemistry. Several contributions in the special issue describe the advantages of the application of chemometric methods in environmental monitoring and research. Others deal with the advantageous application of principles for the design of experiments, multivariate curve resolution, and other multivariate statistical methods for newer analytical principles, like liquid chromatography–tandem mass spectrometry, and force microscopy. The articles published will help to inform the readers of this journal about current trends and applications in chemo-

Anal Bioanal Chem (2008) 390:1225–1226

metrics and, thus, to bring chemometrics closer to the daily working life of the practitioner, not only in the field of analytical chemistry.

Jürgen W. Einax is Professor of Analytical Chemistry at the Friedrich Schiller University of Jena and Head of the Department of Environmental Analysis. His main areas of research include not only trace analysis problems in the environment, but also the application of chemometrics to environmental research. He is a member of the executive board of the Analytical Chemistry Division of the German Chemical Society and is Chairman of the Working Group for Chemometrics and Laboratory Data Processing in that division.