Characterization of Protein in Old Myocardial Infarction by FTIR Micro-spectroscopy

The aim of the present study was to assess whether Fourier transform infrared spectrometry (FTIR) micro-spectroscopy could produce distinct spectral information on protein of old myocardial infarction (OMI) and to set them as molecular markers to diagnose atypical OMI. Paraffin-embedded heart samples were derived from victims dying of OMI. In combination with histological stain, FTIR and infrared micro-spectroscopy, the characteristics of OMI were analyzed morphologically and molecularly. The most relevant bands identified were the amide A, B, Ⅰ and Ⅱ, showing crucial spectral differences between apparent normal region and OMI region, including the peak position blue shift and the increased intensity of OMI, moreover relative increase in α-helix and decrease in β-sheet of protein secondary structures in OMI. Comparing to single spectral band, the I1650/I1550 ratio was increased and rationally used as a molecular marker for diagnosing OMI. These novel preliminary findings supported further exploration of FTIR molecular profiling in clinical or forensic study, and were in accordance with histopathology.

Pyrolysis characteristics of Radix Rhizoma Rhei, Cortex Moudan Radicis, and Radix Sanguisorbae and correlations with the carbonizing process of Chinese herbs

AIM： The aim of the work is to study the pyrolysis characteristics of Radix Rhizoma Rhei, Cortex Moudan Radicis, and Radix Sanguisorbae in an inert atmosphere of argon （Ar）, and to investigate the mechanism of the carbonizing process of the three traditional Chinese herbs. METHODS： The pyrolysis characteristics of the crude materials and their extracts were studied by thermogravimetry-mass spectrometry （TG-MS） in a carrier gas of argon, coupled with Fourier transform infrared spectrometry （FTIR） and scanning electron microscopy （SEM） methods. Correlation of the pyrolysis behaviors with the carbonizing process by stir-frying of traditional Chinese medicines was made. RESULTS： Within the temperature range of 200-300 ℃, which is the testing range for the study of the carbonizing process of Chinese herbs, the temperatures indicated by the maximum weight loss rate peak of the above three extracts were taken as the upper-limit temperatures of the carbonizing process of the herbs, and which were 200, 240 and 247 ℃ for Radix Rhizoma Rhei, Cortex Moudan Radicis, and Radix Sanguisorbae, respectively. The ion monitoring signal peaks detected by the TG-MS method corresponded with reports that the level of chemical components of traditional Chinese medicinal materials would decrease after the carbonizing process. It was confirmed by Fourier transform infrared spectrometry （FTIR） and scanning electron microscopy （SEM） methods that better results of ＂medicinal property preservation＂ could be obtained by heating at 200 ℃ for Radix Rhizoma Rhei, at about 250 ℃ for Cortex Moudan Radicis, and Radix Sanguisorbae, as the relative intensity values of the common peaks were among the middle of their three carbonized samples by programmed heating. CONCLUSION： The upper-limit temperatures of the carbonizing process for Radix Rhizoma Rhei, Cortex Moudan Radicis and Radix Sanguisorbae were 200, 240 and 247 ℃ respectively. It is feasible to research the mechanism and technology of the carbonizing process of traditional Chinese medicinal materials using thermogravimetry, Fourier transform infrared spectrometry, and scanning electron microscopy methods.

Methodological progress in trace amounts of structural water in nominally anhydrous minerals

In the deep Earth, hydrogen mainly occurs as structural hydroxyl and molecular water in minerals and melts, constituting mobile and immobile aqueous components. Hydrous minerals contain hydrogen which occupies a specific structural position and constitutes an indispensable component of chemical formulae. On the other hand, nominally anhydrous minerals do not contain hydrogen in their chemical formulae, but can host trace amounts of water in structural position and lattice defect. The molecular water may occur in the lattice defect as fluid/melt inclusions in minerals. Even though the water content of nominally anhydrous minerals is very limited generally in the order of ppm(parts per million), they may play a significant role in influencing the physicochemical properties of mineral and rock systems. With the continuous improvement of modern instrumentations, the analytical methodology exhibits trends for higher spatial resolution, lower detection limit and integral multiple methods on the water amount and its isotopic ratio. Among these methods, Fourier transform infrared spectrometry remains the most widely used, while secondary ion mass spectrometry, continuous flow mass spectrometry, elastic recoil detection analysis and Raman spectrometry are promising. This paper provides a brief review on the methodological progress and their applications to the analysis of structural water in nominally anhydrous minerals.

Processing of Calamine with Modern Analytical Techniques:Processed with Huanglian Decoction(黄连汤)and Sanhuang Decoction(三黄汤)

Objective： To determine the pyrolysis characteristics of calcined and processed calamine, qualitatively and quantitatively compare the contents of related elements, morphology and functional groups of the pyrolysis products dried at different heating temperatures and explore the critical temperature and the optimal drying temperature for the process of calamine with Huanglian Decoction（HLD, 黄连汤） and San Huang Decoction（SHD, 三黄汤）. Methods： Pyrolysis products were prepared by programmable and constantly heating the calcined and processed calamine to or at different heating temperatures. Thermogravimetry（TG） was used to test their pyrolysis characteristics. Fourier transform infrared spectroscopy and scanning electron microscopeenergy dispersive spectrometer were used to determine their morphology, functional groups and element contents. Page model was used to investigate the constant drying kinetics of processed calamine. Results： The adding of HLD or SHD to calcined calamine（CC） can slow its weight loss in drying pyrolysis process. The temperature ranges where HLD and SHD can affect its weight loss were 65–150 ℃ and 74–180 ℃, respectively. The drying temperature was optimized as 90 ℃. The drying kinetic for the processed calamine fits Page model shows good linearity. Conclusions： The critical temperature and the optimal drying temperature where HLD and SHD can affect the weight loss rate in the process of calamine were explored using the theories and methods of both biophysical chemistry and processing of Chinese materia medica. This work provides a good example for the study of the process of other Chinese medicines using modern analytical techniques.

Crosslinking of PVA Pervaporation Membrane by Maleic Acid

Maleic acid (MA) crosslinked polyvinyl alcohol (PVA) membrane is prepared using a high temperature esterification reaction between PVA and MA in the presence of sulfuric acid as a catalyst. The crosslinking reaction mechanism is investigated using FT IR spectral analysis. The results indicate that maleic acid reacts with hydroxyl groups in PVA to form mono and bis ester in a two step process.

Reaction Mechanism of H2-Assisted C3H6-SCR over Ag-CexZr Catalyst as Investigated by In situ FTIR

A series of silver-doped cerium zirconium oxide(Ag-CevZr)samples was synthesized successfully for selective catalytic reduction of nitric oxide(NO)with hydrogen and propene(H2/C3H6-SCR)under excess oxygen condition.The catalytic activity test proved that Ag-Ce0.4Zr exhibited the best C3H6-SCR activity.Hydrogen(H2)significantly enlianced NO conversion and widened the temperature window.Multi-technology characterizations were conducted to ascertain the properties of fabricated catalysts including X-ray diflraction(XRD),Fourier transform infrared spectrometry(FTIR),scanning electron microscopy(SEM)and H2 temperature programmed reduction(H2-TPR).In situ FTIR results demonstrated that various types of nitrates and chelating nitrite were generated on Ag-CexZr after introduction of NO.Besides,adding H2 could increase the concentration of bidentate nitrate and chelated bidentate nitrate dramatically,especially for Ce0.4Zr catalyst.Transient reaction between pre-adsorbing NO and C3H/C3H6+H2 illuminated that the most active intermediate was chelating nitrite,which was promoted significantly by H2 participation.Furthermore,adding H2 improved the formation of organo-nitro(R-N02),which was the key intennediate in C3H6-SCR.The reaction mechanism over Ag-CexZr catalysts was proposed at 200℃ as follows:nitric oxide(NO)+pr opene(C 3H6)+hy dr ogen(H2)+oxy gen(O2)→chelating nitrite (N O2-)+acry late-type species(CxHyOz)→organo-nitro(R-NO2)→isocyanate(-NCO)+cyanide(—CN)→nitrogen(N2).