Rat liver intoxication with CCl4: biochemistry, histology, and mass spectrometry.

This work provides complex characterisation of cirrhotic rat liver tissue induced by carbon tetrachloride using biochemical and histopathological analyses, and also presents a novel approach, secondary ion mass spectrometry (SIMS). According to our knowledge, this is the first report that compares these three different approaches in study of liver damage. We observed increased levels of triacylglycerols and total cholesterol in the liver and decreased levels of those parameters in the plasma. Histopathological observations include fat accumulation in the cells and changes in internal configuration of cells such as shift of position of organelles from the centre to the edge. The damage to the rat tissue is additionally determined by SIMS analysis, which characterizes, among other substances, diacylglycerols, cholesterol and fatty acids, such as linoleic and oleic acids. Interestingly, unlike other observed particles, a marked difference in SIMS intensity for diacylglycerol C37H69O4 positive fragment at 575.5 m/u was observed. In fact, there was one order of magnitude difference between intoxicated liver samples and controls and this molecular signal seems to be a potential chemical indicator of the damage. The SIMS images are consistent with histopathological results and they additionally provide information about distribution of chemical compound which is a new potential tool for the liver disease characterisation on molecular level.

Surface Nanostructures Composed of Thiolated Cyclodextrin/Au and Fe Species: Gas- and Liquid-Phase Preparation.

Supramolecular surface nanostructures have application potential as functional devices. The complex combination of thiolated cyclodextrin, chemisorbed on an Au surface (Au-S-CD), with deposited Fe species is studied by secondary ion mass spectrometry. The Fe species are prepared by pulsed laser ablation in water and thermal effusion in vacuum. Using laser ablation in water, the solution of Fe species is dropped on Au-S-CD, where mass peaks at 1227 m/z, 1243 m/z, and 1260 m/z are observed and assigned to C42 H68 O34 SNa-Fe(+) , C42 H68 O34 SK-Fe(+) together with C42 H68 O34 SNa-FeO(+) , and C42 H68 O34 SK-FeO(+) , respectively. On the other hand, laser ablation directly linked to the Au-S-CD surface results in desorption of CD-S. Thermal effusion, even with a cooled surface, was negative with respect to the complex observation. Laser ablation results in the formation of a supramolecular host-guest complex of the form Au-S-CD-Fe, and in the formation of an adduct of the form Au-S-CD-FeO.

Fluorescence Dynamics of Monocyclodextrin- and Bis(thiol-cyclodextrin)-Coumarin C153 Complexes.

The solvation and confinement of coumarin C153 within supramolecular host/guest complexes based on ß-cyclodextrin (ß-CD) and 6-deoxy-6-thio-ß-cyclodextrin (ß-CD-SH) in water are studied by fluorescence spectroscopy. For ß-CD/C153, the 1:1 complex is proposed, and for ß-CD-SH/C153 both the 1:1 and 2:1 complexes are believed to be formed. The 2:1 ß-CD-SH/C153 complex has an association constant of 4.2×10(5) M(-1) and a C153 population of 82 %, which are interestingly high values, indicating that the proposed ß-CD-SH dimers structure are connected by covalent disulfide bonds; this is supported by mass spectrometry. Solvation related to fast hydrogen-bond rearrangement as a part of fluorescence relaxation is determined by the ultrafast components of time-resolved spectroscopy to be 3 and 7 ps for the 1:1 ß-CD/C153 and 2:1 ß-CD-SH/C153 complexes, respectively.

Preparation of Cyclodextrin-Iron Species in Water by Laser Ablation: Secondary Ion Mass Spectrometry.

Supramolecular complexes between cyclodextrin and iron species are studied by using secondary ion mass spectrometry. The iron species are prepared by pulsed-laser ablation of bulk iron in water; this gives Fe(+) (56 m/z) and Fex Oy (+) (x, y=1-7) species. Cyclodextrin is added to the water either before or after the laser ablation. When it is added before laser ablation, molecular fragments of cyclodextrin are detected as dehydrated glucopyranose units (C6 H8 O4 (+) ) associated with Fe(+) , FeO(+) , and Fe2 O(+) species. The focus is to observe supramolecular host-guest complexes or adducts between intact molecules of cyclodextrin and iron species. When cyclodextrin is added after laser ablation, the relevant peak at 1210 m/z is observed and assigned as C42 H67 O35 FeNa(+) , which corresponds to a cyclodextrin molecule minus three H atoms. Two possible explanations of this finding are the presence of the host-guest C42 H67 O35 Na-Fe complex, in which Fe is in the cavity, or the presence of the adduct C42 H67 O34 Na-FeO with FeO on the outer surface; the formation of these complexes are supported by the hydrophobicity of Fe and hydrophilicity of FeO, respectively. Due to the presence of 12 % of intact C42 H70 O35 Na-Fe complex and an estimated Fe/FeO ratio of approximately 10(2) , host-guest formation is assumed to be more significant.