Analytical methods novel approaches

Evaluation of a new method may include comparison of results obtained by the analysis of reference materials using established procedures. The purpose is to demonstrate that the novel approach provides results that are at least as reliable as an accepted technique. This same approach may also be used to discover which, of a number of techniques, are preferred. Comparison of analytical techniques and/or methods is considered further in the discussion of external quality assessment, below. 

Liquid-liquid partitioning of the analytes from the soil extract is now being replaced by SPE in many cases to reduce solvent use (Wachob, 1984 Huang, 1989 Wenheng et al., 1991 Redondo et al., 1993 Weil and Haberer, 1991 Mills and Thurman, 1992 Turin and Bowman, 1993 Watts et al., 1994 Ramos et al., 1999). In these methods, the organic component of the extraction solvent is evaporated to leave an aqueous phase for SPE. A novel approach that eliminates the solvent extraction step altogether involves the use of a nonpolar resin placed in contact with water extracts from soil for 5 days, followed by elution. This approach compared well with C18 extraction (Basta and Olness, 1992). 

Wade et al. reported the use of a novel statistical approach for the comparison of analytical methods to measure angiotensin converting enzyme [peptidyl-dipeptidase A] activity, and to measure enalaprilat and benazeprilat [8]. Two methods were used to measure peptidyl-dipeptidase A, namely hippuryl histidyl leucine (HHL-method) [9], and inhibitor binding assay (IBA method) [10]. Three methods were used to measure enalaprilat, namely a radioimmunoassay (RIA) method [11], the HHL method, and the IBA method. Three methods were used to measure benazeprilat (then active metabolite of benazepril) in human plasma, namely gas chromatography-mass spectrometry (GC-MS method) [12], the HHL method, and the IBA method, and were statistically compared. First, the methods were compared by the paired t test or analysis of variance, depending on whether two or three different methods were under comparison. Secondly, the squared coefficients of variation of the... 

Even though, there is no cookbook for HPLC method development this book provides several strategies that the reader could use when presented with a particular situation. These strategies could be stored as tools in the scientists method development arsenal, and drawn from when needed to tackle a particular separation. Moreover, some novel approaches for implementing HPLC, fast HPLC, and hyphenated HPLC techniques towards pharmaceutical analysis are discussed. This book has the potential to serve as a useful resource for the chromatographic community. It can be used as a handbook for the novice as well as the more experienced pharmaceutical chemist who utilizes HPLC as an analytical tool to solve challenging problems regularly in the pharmaceutical industry. 

The function of the chnical chemistry laboratory is to perform quantitative and qualitative analyses on body fluids such as serum, blood, urine, and spinal fluid, as well as other materials such as tissue, calcuh, and feces. The main body of this article describes IR-based methods to carry out some of the most common clinical analytical tests, specifically those involving serum, whole blood, and urine. Fluids that are less commonly assayed (e.g. saliva and amniotic fluid) are also discussed separately. NIR spectroscopy has achieved some notoriety in the chnical chemistry arena because of the early promise that it might serve as the basis for a noninvasive blood glucose test. Some relevant in vitro studies are surveyed briefly here. The article closes with a discussion of novel approaches to derive diagnosis directly, without explicit quantitative analysis, from the spectra of biological fluids. 

One novel approach in the off-Une planar separation method coupled with DIOS is the use of SiNWs as a platform for the separation of molecules [48]. The capabiUty of a SiNW to separate a sample mixture lies in its high surface-to-volume ratio and in the differences in analyte-surface interactions. When combined with an ability to support laser desorption/ionization MS, chromatographic... 

Traceability is also a foundation of method validation. When a method is validated, it means that, properly applied, the method will produce reliable and trustworthy data with a known performance and known limitations. This does not mean that each sample will be the same, but the analytical protocols will be, thereby ensuring optimal performance and comparability of data. Novel samples may require novel approaches, but a standardized and validated method will, at the very least, provide a starting point. Method validation is one of the key components of total quality management in a laboratory. 

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