Samples and Sample Preparation

In order to obtain reliable results, three steps are involved in the analysis sampling and sample preparation carotenoid extraction, separation, identification. 

Zeisler R, Wise SA (1985) Quality assurance and protocols in sampling and sample preparation of biological samples. In Wolf WR, ed. Biological Reference Materials Availability, Uses and Need for Validation of Nutrient Measurement, pp. 257-279. John Wiley and Sons, New York. 

J. Pawliszyn (ed.), Sampling and Sample Preparation for Field and Laboratory, Elsevier, Amsterdam (2003). 

Analyte dilution sacrifices sensitivity. Matrix matching can only be applied for simple matrices, but is clearly not applicable for complex matrices of varying composition. Accurate correction for matrix effect is possible only if the IS is chosen with a mass number as close as possible to that of the analyte elements). Standard addition of a known amount of the element(s) of interest is a safe method for samples of unknown composition and thus unknown matrix effect. Chemical separations avoid spectral interference and allow preconcentration of the analyte elements. Sampling and sample preparation have recently been reviewed [4]. 

J. Begerow and L. Dunemann, in Sampling and Sample Preparation (M. Stoeppler, ed.), Springer-Verlag, Berlin (1997), pp. 155-66. 

Mass spectrometry combines exquisite sensitivity with a precision that often depends more on the uncertainties of sampling and sample preparation than on those of the method itself. Mass spectrometry is a supreme identification and recognition method in polymer/additive analysis through highly accurate masses and fragmentation patterns quantitation is its weakness. Direct mass spectrometry of complex polymeric matrices is feasible, yet not often pursued. Solid probe ToF-MS (DI-HRMS) is a breakthrough. Where used routinely, mass spectrometrists are usually still in charge. At the same time, however, costs need to be watched. 

In some cases the object under study has to be continuously monitored. Then on-line analytical methods are applied by which the system can be directly measured. The analytical process then runs without sampling and sample preparation, as can be seen in Fig. 2.3a. The analytical process is shortened even more in the case of in-line analysis where measurement and... 

A comprehensive review of compositional and failure analysis of polymers, which includes many further examples of analysis of contaminants, inclusions, chemical attack, degradation, etc., was published in 2000 [2], It includes details on methodologies, sampling, and sample preparation, and microscopy, infrared spectroscopy, and thermal analysis techniques. 

In municipalities where the water supplies are from deep-bored wells, samples of household water were collected for Rn-222 analyses. The water samples were analysed by liquid scintillation counting. The method for sampling and sample preparation were adopted from Partridge et al (1979). 

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