Problem solving instrumentation technique

J. Mitchell (ed.), Applied Polymer Analysis and Characterization Recent Developments in Techniques, Instrumentation, Problem Solving, Hanser Publishers, Munich (1987). 

As in the case of all NMR problem-solving, the issue is always one of using the most appropriate tool for the job. The two techniques are in no way mutually exclusive. Too much data is not a bad thing if the instrument time is available but taking a chance on insufficient data can be a costly mistake in the long run. 

When the problem has been defined and needed background information has been studied, it is time to consider which analytical methods will provide the data you need to solve the problem. In selecting techniques, you can refer back to the other chapters in this book. For example, if you want to measure the three heavy metals (Co, Fe, and Ni) that were suspect in the Bulging Drum Problem, you might immediately think of atomic absorption or inductively coupled plasma atomic emission spectroscopies and reread Chapter 8 of this book. How would you choose between them Which would be more accurate More precise Does your lab have both instruments Are they both in working order What if you have neither of them What sample preparation would be needed ... 

NMR offers many unique advantages that other methods cannot provide in spite of some limitations. Biopharmaceutical product development will certainly benefit from including NMR as an option for solving analytical problems. NMR instrumentation and methodology are constantly being improved. As better and more sensitive NMR techniques become available, the use of NMR as a standard analytical tool in biopharmaceutical process development and validation is expected to increase. 

J. G. Grasselli, S. E. Mocadlo, and J. R. Mooney, in Applied Polymer Analysis and Characterization Recent Developments in Techniques, Instrumentation, Problem Solving (J. Mitchell, Jr., ed.), Chap. III-A, Hanser Publishers, New York, 1987. 

Background. As an analytical technique, tandem mass spectrometry is just entering its second decade of development. The variety of reported applications belies its relative youth. Tandem mass spectrometry (MS/MS) grew out of early work which used metastable ion transitions in order to establish ion structures and interrelationships. After extensive applications to ion structural studies, its usefulness in direct catplex mixture analysis became apparent with the early work of Cooks (1-3). Its successes in problem solving are summarized in a recent book edited by McLafferty (4). New, with several ccnmercial instruments available, MS/MS is being evaluated for application in several new areas, including biochemical analysis, forensic chemistry, and food and flavor analyses. The principles of MS/MS will be surmarized in the first part of this chapter. The second part of the chapter will deal with the reported applications of MS/MS to flavor analysis. 

Hyphenated techniques refer to the combination of one or more analytical techniques for problem solving and fundamental research. Numerous types have been reported in the scientific journals. Frequently the FTIR spectrometer is coupled with chromatographic instruments for the structural characterization of a column eluent. These systems are designed to monitor the eluent or to obtain its spectrum. Much of the development has been focused on the sampling technique and the design of the interface between the chromatographic system and the FTIR spectrometer to improve the performance of the system. 

ICP-OES continues to dominate the market because of its ease of use and relatively low maintenance cost. Inductively coupled plasma mass spectrometry (ICP-MS) is a very powerful state-of-the-art technique used for metal analysis of all kinds of samples but requires highly skilled operators. A vast amount of information is received that is not necessarily required as part of problem-solving or routine support. The cost difference and relative freedom from maintenance problems would favour ICP-OES. This book is aimed at practitioners requiring multi-elemental analysis in industrial, environmental, pharmaceutical and research laboratories, where information on identification and quantification is required on a regular basis. The main focus of this book will be on sample preparation, a topic overlooked in most books on atomic spectroscopy. It is aimed at most ICP-OES and ICP-MS users to show that the instrument is useless unless the sample is prepared in a suitable state that can be used to accurately and precisely quantify the metals present. 

Regardless of the analytical instrumentation mix, the art of problem-solving remains. A person or team must make the decisions about analysis what, when, and how. There must be an analytical "ejqpert" be it man or computer, who can make choices of appropriate technique. 

Even though technological advances might Improve the resolution of some of our Instrumentation, miniaturization itself will only complicate our ability to characterize devices In the future. Artificial intelligence and expert systems appear to have an excellent potential for enhancing our problem solving ability. It Is expected that with proper development, this tool could become an essential Item In the microanalyst s repertoire of techniques In tomorrow s technology. 

In many industrial laboratories, the analytical chemist is often viewed as a valuable resource for solving manufacturing, research, and development problems. Samples requiring analysis enter the laboratory and results and solutions for problems are generated. To complete this task, the analytical laboratory must possess a wealth of resources, both in instrumentation and in experienced personnel, so that a number of assays may be conducted to generate the data that are required to solve a particular problem. As the techniques in an analytical laboratory are enumerated, each provides data that are unique to that assay. Often, it is only after the initial characterization... 

Volume 37 of Metkods of Biochemical Analysis focuses on the application of special instrumental techniques to problems in biology. Focusing selected volumes of this series on instrumentation is particularly appropriate because advances in instrumentation often times provide new vistas in science. The development of the pH meter, spectrophotometer, radioactivity and the associated measuring devices early in this century had a significant impact on research in many areas of biology and biochemistry. Likewise the instrumentation reviewed in this volume have and will continue to have a significant affect on the rate in which we solve problems. 

It is becoming more and more desirable for the analytical chemist to move away from the laboratory and into the field via in-field instruments and remote, point of use, measurements. As a result, process analytical chemistry has imdeigone an offensive thmst in regard to problem solving capabiUty (77—79). In situ analysis enables the study of key process parameters for the purpose of definition and subsequent optimization. On-line analysis capabiUty has already been extended to gc, Ic, ms, and ftir techniques as well as to icp-emission spectroscopy, flow injection analysis, and near infrared spectrophotometry (80). 

In 1990, Chemical Abstracts Service listed over 10 million substances in their Registry. Moreover, the growth of new compounds is exponential, leading to a doubling of known chemicals every eleven years. Thus there is an ever increasing need to efficiently identify substances and quantitate material with high confidence. Hyphenated instruments, combinations of accepted instrumental techniques where the sample is passed from one instalment direcdy into another, were developed to aid in solving this problem (1). 

The strength of an instrumental technique relies on its ability to solve analytical problems efiectively. This gen ization is certainly true for LCEC methodology, where the whole of analytical methodology in neurochemistry, for example, was revamped in its favor. Well over 800 publications in the journal literature have employed LCEC to solve neurochemical problems which would otherwise have been more time-consuming or otherwise impossible to attack. There exist another 300-400 papers on applica-... 

A. Lee Smith,. Applied Infrared Spectroscopy Fundamentals, Techniques, and Analytical Problem-Solving. New York Wiley, 1979. Comprehensive treatment of IR spectroscopy. Includes history, instrumentation, sampling techniques, qualitative and quantitative applications. 

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