Pharmacology, activation analysis applications

The concept of impurity profiling is very important for antibiotics, since most of them are still produced by fermentation or by semisynthesis starting from fermentation products. Antibiotics are typically complex mixtures of several components and their composition depends on the fermentation conditions. Impurities due to degradation occur frequently. Commercial samples usually contain significant amounts of impurities with only minor structural differences among them, but differing widely in their pharmacological activities. These impurities can exhibit antibiotic activity, but in many cases they are inactive and sometimes even toxic. The applicability of CE in the analysis of antibiotics has been reviewed elsewhere. The use of CZE in impurity analysis of antibiotics is discussed in detail below. 

Extraction of Active Compounds from Plant Materials. A variety of natural products present in plant materials, especially high-value-added products, can be processed with supercritical fluids. Because many of these have pharmacological activity, a natural extension of this application is to the field of drug analysis. 

Determination of Element Species The determination of total element concentrations of PGM in various matrices is sufficient for a first understanding, but a more differentiated analysis is often necessary, in particular with regard to questions concerning bioavaUability, toxicology, pharmacological activity, and pharmacokinetics. The required determination of bonding types and/or bonding partners of the PGM (speci-ation) in environmental samples is rather difficult due to the often very small analyte masses of these elements that usually show intrinsically low natural concentrations. Moreover, the concentrations are further decreased by the limited sample amounts applicable for the separation procedure and the separation into different fractions. Therefore, despite the impressively low LODs of modem analytical methods, the speciation of PGM still often reaches the current analytical limits. 

Loveridge and Smales (560) were the first to publish an extensive paper about the applications of activation analysis to biochemistry. Their report covered the period 1944-1957. Since then many other review articles have been written about its capabilities as a methodology to analyze for trace substances in problems from medicine, veterinary medicine, forensic medicine, dental science, pharmacology, botany and agriculture. More specifically, these articles can be categorized in the following manner ... 

Ion-selective electrodes are widely used in pharmaceutical analysis. Numerous ion-selective electrodes based on poly(vinyl)chloride (PVC) have been constructed in order to determine various pharmacologically active substances in pharmaceutical preparations. The inherent advantages of ISE-s are simple design, construction and manipulation, reasonable selectivity, fast response time, low cost, adequate detection limit and adequate precision and accuracy. Therefore, the ISE potentiometric method is very attractive for pharmaceutical analysis. The first part of this chapter describes the properties and uses of PVC, as well as the general characteristics and preparation of the polymer membranes of ion-selective electrodes. The second part deals with the development of solid contact electrodes formed on non-crystal electrodes with a microporous matrix (e.g., vinyl polychloride dissolved in an appropriate modifier) selective for various nonsteroidal anti-inflammatory drugs (NSAlD-s) and their applications in pharmaceutical research. 

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