Contemporary methods

In response to the need for rapid and simple methods for the detection of short-chain organic acids in complex matrices, a technique was developed that very well suited the specific purpose of CE. This method employed indirect detection and a surfactant to reverse electro-osmotic flow. Direct UV detection provides higher sensitivity and precision and the ability to detect UV-absorbing organic acids, such as oxalic, fumaric, or pyroglutamic acids, which cannot be detected with the indirect system (Galli and Barbas, 2004). 

Most anionic compounds can be analyzed simultaneously without derivatization. 

A distinct electrophoretogram is produced without other matrix interferences. 

Detection method Specific/ proposed uses Advantage Limitations 

High performance Determination of Simultaneous Lacks specificity 

---

Penney discusses contemporary methods of addressing dissolved gases and makes recommendations of his own with plant examples. Basically his recommendations are as follows. When mechanical damage is of prime... 

F. Sato developed titanium (Il)-based c/s-reduction of alkynes as shown in Scheme 5 [14], and the method was applied to the synthesis of pheromones by Kitching (Scheme 6) [15]. This titanium (Il)-based reaction gives pure (Z)-alkenes. Kitching summarized the contemporary methods for the synthesis of skipped polyynes and their reduction to skipped polyenes [15]. 

This chapter will cover recent developments in the design of diverse and protein family-targeted libraries, their physicochemical properties, and contemporary methods for screening them. 

Comments on Contemporary Methods of Oxygen and Nitrogen Free Radical Detection... 

P.J.Schoenmakers and M.Mulholland, An Overview of Contemporary Method Development in Liquid Chromatography, Chromatographia, 25(8) (1988) 737-748. 

Savelyev VS, Filimonov MI, Gelfand BR, Bumevich SZ, Sobolev PP (1996) Assessment of efficiency of contemporary methods of treatment of destructive pancreatitis. Annals of Surgical Hepatology 1 58-61... 

Contemporary methods for peptide and protein synthesis, Aimoto, S. Curr. Org. Chem. 2001, 5, 45-87. 

The assessment of the chelating ability of macroligands and applicability of such systems requires the data on the quantitative evaluation of the chelation processes such a stability constants and formation function. Contemporary methods are largely based on the composition of the products formed. The major methods of analyzing the quantitative parameters of MX chelation use predominantly the same techniques that are applied to the description of complexing reactions with participation of monofunctional macroligands [5, 7b, 13a]. 

A greater variety of classic and contemporary methods are available for the sequencing of RNA. A thorough description of existing methodologies of more current utility are found in Stahl et a/.12 However, as for DNA sequencing, the two most commonly applied methods for RNA sequenc-... 

In contemporary methods, the assay of corticosterone is performed by immunoassay in unextracted serum samples or in serum and tissue extracts by HPLC. In the classical methods, fluorometry was applied. Pekkarinen (1965) used fluorometric corticosteroid... 

This chapter discusses the synthesis of transition metal dithiolene complexes and is current to late 2002. Dithiolene chemistry has been reviewed several times previously, but this is the first review dedicated to synthetic aspects. Emphasis is placed on more contemporary methods, and the reader should consult the older reviews, especially those by Mueller-Westerhoff et al. (8) and McCleverty (9) for discussions of earlier literature. An effort was made to be comprehensive with respect to methods and the range of complexes examined, but the chemistry of metal dithiolenes is so vast that it is not practical to be exhaustive. 

Gutman I, Dias JR (1990) In Bodendiek R (ed) Contemporary methods in graph theory, Bl-Wissenschaftsverlag, Mannheim, pp 249-259... 

Contemporary methods of trace analysis such as NAA, ICP-OES, and ICP-MS make possible simultaneous determination of several elements. Determination of only one or two elements is relatively rarely, requested. Therefore the CRM certified for many trace elements helps to save time and money. 

We now find ourselves familiar with methods of constructing a carbon skeleton for an organic molecule, how to introduce and transform functional groups, and how to achieve the required selectivity. One could almost expect the rich arsenal of contemporary methods to enable the chemist to solve practically any problem of synthetic chemistry. Yet it is not quite so simple. It is imperative to be skillful in planning a synthesis, to be able not only to master its tactics, but its overall strategy as well. 

Contemporary methods for sohd-phase couplings of peptide fragments are based on the use of phosphonium or uronium salts. HOBt was introduced as an additive with BOP, and more recently HOAt was used as an alternative in carbodiimide couplings instead of HOBt and shown to be more effective. Phosphonium and uronium salts of HOAt, namely PyAOP, HATU, and HAPyU, have also been used with success in CSPPS. 

In particular, this chapter wiU stress the need to look beyond the classic radical chain reaction. Lipid oxidation mechanisms have been proposed based on kinetics, usually of oxygen consumption or appearance of specific products (e.g., LOOK) or carbonyls (e.g., malonaldehyde), assuming standard radical chain reaction sequences. However, when side reactions are ignored or reactions proceed by a pathway different from that being measured, erroneous conclusions can easily be drawn. The same argument holds for catalytic mechanisms, as will be shown in the discussion about metals. In the past, separation and analysis of products was laborious, but contemporary methods allow much more sensitive detection and identification of a broad mix of products. Thus, multiple pathways and reaction tracks need to be evaluated simultaneously to develop an accurate picture of lipid oxidation in model systems, foods, and biological tissues. 

---