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C. Paschke A. Leisner A. Hester K. Maass S. Guenther W. Bouschen B. Spengler 《Journal of the American Society for Mass Spectrometry》2013,24(8):1296-1306
Mass spectrometric imaging (MSI) techniques are of growing interest for the Life Sciences. In recent years, the development of new instruments employing ion sources that are tailored for spatial scanning allowed the acquisition of large data sets. A subsequent data processing, however, is still a bottleneck in the analytical process, as a manual data interpretation is impossible within a reasonable time frame. The transformation of mass spectrometric data into spatial distribution images of detected compounds turned out to be the most appropriate method to visualize the results of such scans, as humans are able to interpret images faster and easier than plain numbers. Image generation, thus, is a time-consuming and complex yet very efficient task. The free software package “Mirion,” presented in this paper, allows the handling and analysis of data sets acquired by mass spectrometry imaging. Mirion can be used for image processing of MSI data obtained from many different sources, as it uses the HUPO-PSI-based standard data format imzML, which is implemented in the proprietary software of most of the mass spectrometer companies. Different graphical representations of the recorded data are available. Furthermore, automatic calculation and overlay of mass spectrometric images promotes direct comparison of different analytes for data evaluation. The program also includes tools for image processing and image analysis. Figure
? 相似文献
43.
In this study, the potential of N-alkoxymethyl groups as protectants for the peptide backbone has been investigated. These groups were found to be compatible with the standard conditions of Fmoc/tBu SPPS, and can be cleaved off from the peptide backbone by acids. Thus, backbone N-alkoxymethyl groups may be useful to prevent undesired side-reactions and/or interchain aggregation during peptide elongation on the solid-phase. However, the main issue for their application as protecting groups is the difficulty to incorporate them into the peptide backbone. 相似文献
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Hinz KP Gelhausen E Schäfer KC Takats Z Spengler B 《Analytical and bioanalytical chemistry》2011,401(10):3165-3172
A new method is presented using an optical particle counter and the compact mobile laser mass spectrometer LAMPAS 3 for in
situ analysis of single particles generated by electrosurgical dissection of biological tissues. The instrumental performance
is demonstrated for analysing aerosol particles formed during rapid thermal evaporation of porcine liver and porcine kidney
tissues. Particle number concentrations of up to 5,000 particles per cubic centimetre were detected during surgical dissection.
Chemical analysis of tissue particles was performed by bipolar time-of-flight mass spectrometry. The application of an online
mass spectrometric particle analysis for surgical aerosols is reported here for the first time. 相似文献
47.
Guenther S Schäfer KC Balog J Dénes J Majoros T Albrecht K Tóth M Spengler B Takáts Z 《Journal of the American Society for Mass Spectrometry》2011,22(11):2082-2089
The feasibility of electrospray (ES) ionization of aerosols generated by electrosurgical disintegration methods was investigated.
Although electrosurgery itself was demonstrated to produce gaseous ions, post-ionization methods were implemented to enhance
the ion yield, especially in those cases when the ion current produced by the applied electrosurgical method is not sufficient
for MS analysis. Post-ionization was implemented by mounting an ES emitter onto a Venturi pump, which is used for ion transfer.
The effect of various parameters including geometry, high voltage setting, flow parameters, and solvent composition was investigated
in detail. Experimental setups were optimized accordingly. ES post-ionization was found to yield spectra similar to those
obtained by the REIMS technique, featuring predominantly lipid-type species. Signal enhancement was 20- to 50-fold compared
with electrosurgical disintegration in positive mode, while no improvement was observed in negative mode. ES post-ionization
was also demonstrated to allow the detection of non-lipid type species in the electrosurgical aerosol, including drug molecules.
Since the tissue specificity of the MS data was preserved in the ES post-ionization setup, feasibility of tissue identification
was demonstrated using different electrosurgical methods. 相似文献
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A. Ruebner J. G. Moser D. Kirsch B. Spengler S. Andrees S. Roehrs 《Journal of inclusion phenomena and macrocyclic chemistry》1996,25(1-3):35-38
The aim of our investigation was the development of carrier systems for an application of inert drugs in polyphasic photodynamic tumor therapy. As carrier systems, -cyclodextrin dimers linked at their primary and secondary faces by spacers of varying lengths were synthesized. Cyclodextrins are known to form stable inclusion complexes with porphyrinoïd photosensitizers. The influence of spacer length on the -cyclodextrin dimer inclusion complexes with porphyrinoïd photosensitizers was studied. 相似文献