Mass spectra of six representative underivatized steroids and three parent hydrocarbons were obtained using laser desorption/Fourier transform (LD/FT) mass spectrometry. The carbonyl steroids, with the exception of aldosterone, yielded abundant [M + H]+ ions. For cholesterol, a major fragment ion was that corresponding to dehydration. The hydrocarbons produced [M + H]+, M+ and [M - H]+ ions, in addition to expected alkyl cleavage ions including those resulting from methyl loss. The LD/FT mass spectra of all were qualitatively similar to electron ionization spectra, but showed somewhat less fragmentation.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/bms.1200151106 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Fabricating a PDA-Liposome Dual-Film Coated Hollow Mesoporous Silica Nanoplatform for Chemo-Photothermal Synergistic Antitumor Therapy.
Pharmaceutics
April 2023
School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China.
In this study, we synthesized hollow mesoporous silica nanoparticles (HMSNs) coated with polydopamine (PDA) and a D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS)-modified hybrid lipid membrane (denoted as HMSNs-PDA@liposome-TPGS) to load doxorubicin (DOX), which achieved the integration of chemotherapy and photothermal therapy (PTT). Dynamic light scattering (DLS), transmission electron microscopy (TEM), N adsorption/desorption, Fourier transform infrared spectrometry (FT-IR), and small-angle X-ray scattering (SAXS) were used to show the successful fabrication of the nanocarrier. Simultaneously, in vitro drug release experiments showed the pH/NIR-laser-triggered DOX release profiles, which could enhance the synergistic therapeutic anticancer effect.
View Article and Find Full Text PDFForensic investigation of arson residue by infrared and Raman spectroscopy: From conventional to non-destructive techniques.
Med Sci Law
July 2020
Dr A.P.J. Abdul Kalam Institute of Forensic Science and Criminology, Bundelkhand University, India.
Arson can result in highly challenging and complicated crime scenes. Much physical evidence undergoes chemical degradation because of the destructive nature of fire, while accelerants either completely burn or evaporate, and may be present in traces within any of the decomposed materials. To identify the original material and the accelerant involved, it is necessary to use advanced analytical techniques.
View Article and Find Full Text PDFWide mass range trapping using a 7-T internal source matrix-assisted laser desorption/ionization Fourier transform mass spectrometer.
Anal Bioanal Chem
October 2008
Chemistry and Biochemistry Department, University of Arkansas, Fayetteville, AR 72701, USA.
A wide mass range trapping experiment using internal source matrix-assisted laser desorption-Fourier transform mass spectrometry (MALDI-FTMS) was evaluated. In this method, the front trap plate potential is ramped up and the rear trap plate potential is simultaneously decreased using a cubic cell to trap ions over a wide range of mass-to-charge ratios. To apply this to MS/MS experiments, a second ion ejection procedure would remove unwanted ions, with the selected remaining ions then fragmented by collision-induced dissociation.
View Article and Find Full Text PDFGlycine identification in natural jarosites using laser desorption Fourier transform mass spectrometry: implications for the search for life on Mars.
Astrobiology
April 2008
Geosciences Department, University of Montana, Missoula, Montana 59812, USA.
The jarosite group minerals have received increasing attention since the discovery of jarosite on the martian surface by the Mars Exploration Rover Opportunity. Given that jarosite can incorporate foreign ions within its structure, we have investigated the use of jarosite as an indicator of aqueous and biological processes on Earth and Mars. The use of laser desorption Fourier transform mass spectrometry has revealed the presence of organic matter in several jarosite samples from various locations worldwide.
View Article and Find Full Text PDFAnalysis of base oil fractions by ClMn(H2O)+ chemical ionization combined with laser-induced acoustic desorption/fourier transform ion cyclotron resonance mass spectrometry.
Anal Chem
March 2008
Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Laser-induced acoustic desorption (LIAD), combined with chemical ionization with the ClMn(H(2)O)(+) ion, is demonstrated to facilitate the analysis of base oils by Fourier transform ion cyclotron resonance mass spectrometry. The LIAD/ClMn(H(2)O)(+) method produces only one product ion, [ClMn + M](+), for each component (M) in base oils, thus providing molecular weight (MW) information for the analytes. With the exception of one sample, no fragmentation was observed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!