Sample preparation protocols for

E. Nordhoff, M. Schurenberg, G. Thiele, C. Lubbert, K.-D. Kloeppel, D. Theiss, H. Lehrach, and J. Gobom. Sample Preparation Protocols for MALDI-MS of Peptides and Oligonucleotides Using Prestructured Sample Supports. Int. J. Mass Spectrom., 226(2003) 163-180. 

The panel meeting was organized and conducted to facilitate development of sample preparation protocols for mutagenicity testing of six media air, drinking water, nonaqueous liquid wastes, soils and sediments, waste solids, and waste water. The meeting objectives were established by the sponsors and were as follows ... 

Evaluate the adequacy and validity of the selected and reviewed sample preparation protocol for each medium. 

TABLE 10.5. The SDS-PAGE, Enzymatic Digestion, and Sample Preparation Protocols for MS/MS Analysis of Wine Proteins2... 

Nordhoff, E., Schuerenberg, M., Thiele, G. Lubbert, C., Kloeppel, K.-D., Theiss, D., Lehrach, H., and Gobom, J. (2003) Sample preparation protocols for MALDI-MS of peptides and oligonucleotides using prestructured sample supports. Int. J. Mass. Spectrom. 226, 163-180. 

The current MALDI techniques used for polymer analysis have several limitations. For example, they are unable to analyze some narrow-polydispersity polymers, while there is a need to develop sample-preparation protocols for the analysis of important polymers such as polyethylene, perfluoropolymer, and polycationic materials. Although the analysis of polystyrenes with molecular masses of up to 1.5 million using a conventional MALDI-TOF instrument has been demonstrated, it remains to be seen how the technique can be appUed to other high-mass polymers (>500000 Da). 

Typical sample preparation protocols for MALDI (see below) involve additives such as acids for analytes with basic functionalities like proteins and peptides, or metal... 

FIGURE 14.8 Sample preparation protocol for the analysis of oxysterols in brain, CSF, or plasma. 

Currently, most of the rapid microbial analyses are based on MALDl techniques. Selecting an optimal matrix is a cracial step in developing all of the sample preparation protocols for the MALDI-MS. The MALDl matrices that are frequently used for microbial analysis are a-cyano-4-hydroxycinnamic acid (CHCA), feralic acid (FA), and sinapinic acid (SA). It has been demonstrated that the use of a different matrix for the same kind of sample led to a significant change in the MALDl mass spectrum. For example, the MALDl mass spectra of E. coli obtained with CHCA and a mixture of SA/4-methoxycinnamic acid showed significantly different signals (Demirev et al. 1999). CHCA is one of the most common matrix for bacterial identification. 

The selection of a proper cultivation medium can serve as a tool to increase the discriminatoiy power of the method for mycobacteria at the strain level. Optimization of the sample preparation protocol for distinguishing between selected groups... 

Need for sample preparation protocols for POs, per-lluoropolymers, and polycationic polymers... 

A number of papers have been published that compare the effects of different sample preparation protocols for FTIR and Raman microspectroscopic studies, and these are discussed in the following sections. 

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