Distribution studies MALDI

Hensley ei al.,n reported the only direct experimental observation of head-to-head linkages in PS by 2D INADEQUATE NMR on, 3C-enriched PS. The method did not enable these groups to be quantified with sufficient precision for evaluation of W tc- Zammit el a/.130 studied chain distribution of low molecular weight PS prepared with AIBN initiator by MALDI-TOF. Separate distributions of chains formed by combination and disproportionation were observed. They estimated kJkK. at 90 °C to be 0.057. 

In a separate study, a protocol for Matrix-assisted laser desorption-ionization (MALDI) imaging mass spectrometry (IMS) has been proposed.18 This IMS technique provides a new approach to visualize spatial distribution of thousands of molecular species, including peptides, proteins, and their metabolites in two- or three-dimensional levels. This approach may also provide a straightforward method of determining the tissue distribution of multiple peptides or proteins in a quantitative manner.18 Chu et al.19 reported a nondestructive molecular extraction method to obtain proteins from a single FFPE or frozen tissue section, without destroying the tissue morphology, such... 

In 2006, Lobinski et al.1 reported on the imaging and speciation analysis of trace elements to study the element distribution, oxidation state, metal site and metal structure in biological environments using mass spectrometric techniques (LA-ICP-MS, SIMS, MALDI-MS) and non-mass-spectrometric techniques such as micro-PIXE (proton induced X-ray emission), XANES (X-ray absorption near edge structure) and EXAFS (extended X-ray absorption fine structure) -the latter two techniques are very sensitive due the use of a more intense synchrotron beam.1... 

The use of MALDI to image biological materials is another interesting application [33,34], Indeed, as with LD and SIMS, MALDI has been used to map the distribution of targeted biomolecules in tissue. It allows for example the study of peptides, proteins and other biomolecules directly on tissue sections. 

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