Characterization of synthetic

Li, S. and Dass, C., Iron(III)-Immobilized Metal Ion Affinity Chromatography and Mass Spectrometry for the Purification and Characterization of Synthetic Phosphopeptides, Anal. Biochem., 270, 9, 1999. 

Engelhardt, H. and Martin, H. Characterization of Synthetic Polyelectrolytes by Capillary Electrophoretic Methods. Vol. 165, pp. 211-247. 

In conclusion, it may be stated that Py-GC/MS is the method of choice for chemical characterization of synthetic polymers used in artworks or as conservation materials. The chemical information is generally specific for the individual component, and the amount of sample required is practically negligible, thus allowing application of the technique even... 

The drive for the synthesis and characterization of synthetic coordination polymers was catalyzed by work supported and conducted by the U.S. Air Force in a search for materials which exhibited high thermal stabilities. Attempts to prepare highly stable, tractable coordination polymers were disappointing. Typically, only oligomeric products were formed and the monomeric versions were often more stable than the polymeric versions. 

MALDI measures the mass very accurately, and it gives an absolute measurement of mass. Still, sample and solution conditions must be optimized for the best performance of the matrix and therefore, it cannot yet be used as a routine method. Also, characterization of synthetic polymers by MALDI is sometimes... 

SEC is presently the most important method for separation and molecular characterization of synthetic polymers. The exclusion chromatography of lipophilic macromolecules is called also gel permeation chromatography (GPC) and for hydrophilic species, the term gel filtration chromatography (GFC) is often applied. It seems that the term gel permeation chromatography is returning probably because the abbreviation SEC means also Securities and Exchange Commission. 

Mass spectrometry has gained widespread application for the characterization of synthetic peptides and has led, in combination with HPLC, to the identification of accompanying byproducts such as polysulfides 17 ... 

Great care has to be taken in the analytical characterization of synthetic cyclic peptides.[73] The major side reactions during cyclization are epimerization of the C-terminal amino acid residue and cyclodimerization. Cyclodimers can be detected by mass spectrometry, although the analysis is not trivial, because artifacts do occur in some ionization techniques such as ES-MS as a result of aggregation.1 1 Ll 121 Real dimers can be detected as double-charged particles with mlz values identical to the cyclic monomers, but with a mass difference of 0.5 amu in the resolved isotope signals. The mass difference of the corresponding monomer is 1 amu. The cyclodimerization has received some attention as a direct method for the synthesis of C2-symmetrical cyclic peptides.[62 67 94113 115]... 

For the study of colloidal interactions, SANS gives higher signal to noise ratio and can be used to lower Q than SAXS. It has been widely used for the characterization of synthetic microemulsions. Application to food systems has been more limited, but one example is described below. A study of voids in food solids is noted. 

Taylor and co-workers further demonstrated the value of open-access LC/MS systems for generating a widened scope of pharmaceutical analysis applications, including (1) characterization of synthetic intermediates and target compounds (2) reaction monitoring (3) reaction optimization (4) analysis of preparative HPLC fractions and (5) analysis of thin layer chromatography (TLC) plate spots. The availability of these methods led to the increased use of LC/MS for structural analysis. The short analysis time and reliable structure confirmation resulted in the use of LC/MS as a first choice for structure characterization for synthetic chemistry applications, as well as an expanded, and perhaps, integrated role of sample generator and analyst. 

Another chromatographic method, which is related to HPLC, is Size Exclusion Chromatography.16 In this technique, separation is based on molecular size. The analytes do not interact with the column material, but are separated on basis of the amount of pores into which they may penetrate. SEC is used for the separation and characterization of synthetic and natural water-soluble polymers. Organic or silica-... 

Characterization of Synthetic Polyelectrolytes by Capillary Electrophoretic Methods... 

Sepetov N, Issakova O, Analytical characterization of synthetic organic libraries, in Combinatorial Chemistry and Combinatorial Technologies Methods and Applications (Eds. Fassina G, Miertus S), 237-268, 1998, 2005, Chapter 10, this volume. 

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