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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Li Yu-guo
,
Huang Xuan
,
Liu Riu-li
,
Li Qing-nuan
,
Zhang Xiao-dong
, and
Li Wen-xin

Summary  

The water-soluble fullerene derivative C60(OH)x was radiolabeled with 67GaCl3. The labeling yields were determined by radio-PLC. The effects of pH, reaction time, temperature and the amount of C60(OH)x on the labeling yields were studied. The stability of 67Ga-C60(OH)x was also examined. The results showed that the labeling yields could reach 97% under the best labeling conditions and the radiochemical purity of 67Ga-C60(OH)x solution kept at 37 °C remained at 88% after 212 hours. The biodistribution studies of 67Ga-C60(OH)x in mice showed a high localization of 67Ga-C60(OH)x in the bone marrow, bone, liver and spleen with slow clearance and a negligible accumulation in the blood. These data suggest that the water-soluble C60(OH)x, having the same properties as microcolloids, may be used as a carrier of drug system for lymphatic targeting.

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The thermal decomposition process of the complex [Cu(NBOCTB)][Cu(NO3)4] H2O has been studied by TG and DTG technique, and possible intermediates of the thermal decomposition have also been conjectured from the TG and DTG curves. The results suggest that the decomposition of the complex involves five steps:

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Abstract  

Differential elastic scattering cross sections for backscattering of 0.96–2.74 MeV protons incident on an aluminum layer covered by a gold layer deposited on a graphite crystal have been measured. The lowest proton energy in the experiment is in the Rutherford backscattering energy region. The measured cross sections are compared with the previous data and presented in graphical and tabular forms.

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Abstract

The stability of β-cyclodextrin-cinnamyl alcohol inclusion complex (β-CD·C9H10·8H2O) was investigated using TG and DSC. The mass loss took place in three stages: the dehydration occurred between 50–120°C; the dissociation of β-CD·C9H10O occurred in the range of 210–260°C; and the decomposition of β-CD began at 280°C. The dissociation of β-CD·C9H10O was studied by means of thermogravimetry, and the results showed: the dissociation of β-CD·C9H10O was dominated by a two-dimensional diffusion process (D2). The activation energyE was 161.2 kJ mol−1, the pre-exponential factorA was 4.5×1013 min−1.

Cyclodextrin is able to form inclusion complexes with a great variety of guest molecules, and the interesting of studies focussed on the energy binding cyclodextrin and the guest molecule.

In this paper, β-cyclodextrin-cinnamyl alcohol inclusion complex was studied by fluorescence spectrophotometry and infrared absorption spectroscopy, and the results show: the stable energy of inclusion complexes of β-CD with weakly polar guest molecules consists mainly of Van der Waals interaction.

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Abstract

The stability of the inclusion complex of β-CD with cinnamic aldehyde was investigated by means of TG and DSC. The mass loss takes place in three stages: dehydration occurs at 50–120°C; dissociation of β-CD·C9H8O proceeds in the range 200–260°C; and decomposition of β-CD begins at 280°C. The kinetics of the dissociation of β-CD·C9H8O was studied by means of thermogravimetry both at constant temperature and with linearly increasing temperature. The results demonstrate that the dissociation of β-CD·C9H8O is dominated by a one-dimensional diffusion process. The activation energyE is 160 kJ mol−1, and the pre-exponential factorA is 5.8×1014 min−1. Scanning electron microscope observations and the results of crystal structure analysis are in good agreement with those of thermogravimetry.

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Abstract

Splenic lymphocytes play an important role in host acute or chronic diseases. The abnormality of these cells in the spleens of humans might lead to some riskful diseases for human. Hence, in this study, the effects of two ginsenosides Rg1 and Rb1 on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power-time curves, growth rate constant k, maximum heat-output power of the exponential phase P max, total heat output Q t of splenic lymphocytes were obtained to present the effects of Rg1 and Rb1 on these cells. The values of k, P max, and Q t from the thermogenic growth curves of splenic lymphocytes were found to increase in the presence of Rg1, while the change was adverse for Rb1, illustrating that Rg1 had promotion effect and Rb1 had inhibitory effect on splenic lymphocytes growth and these promotion or inhibitory effects were enhanced with increasing the concentration of the two compounds, respectively. The microcalorimetric results were confirmed by MTT assay for determining the MTT optical density (OD) value and [3H] Thymidine incorporation assay ([3H]-TdR) for determining the count per minute (cpm) value: Rg1 could increase the MTT OD value and the cpm value of [3H]-TdR incorporation into splenic lymphocytes, and these values were increased with increasing the concentration of this compound, while Rb1 had the adverse results. The structure–activity relationships showed that the glucopyranoside and hydroxyl groups at the dammarane-type mother nucleus skeleton might play a crucial role for the opposing effects of the two ginsenosides on splenic lymphocytes. Compared with the other two assay methods, the microcalorimetric method provided more useful and reliable information for quickly and objectively evaluating the effects of drugs or compounds on the living cells, which would be a highly promising analytical tool for the characterization of the biological process and the estimation of the drugs’ efficiency.

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Abstract

In this study, the activities of four ginsenosides Rc, Re, Rd, and Rf on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power–time curves, growth rate constant k, maximum heat-output power of the exponential phase P max and the corresponding appearance peak time t max, total heat output Q t, and promotion rate R p of splenic lymphocytes growth affected by the four ginsenosides were calculated. In accordance with thermo-kinetic model, the corresponding quantitative relationships of k, P max, t max, Q t, R p, and c were established. Also, the median effective concentration (EC50) was obtained by quantitative analysis. Based on both the quantitative quantity–activity relationships (QQAR) and EC50, the sequence of promotion activity was Rc > Re > Rd > Rf. The analysis of structure–activity relationships showed that the number, type, and position of sugar moieties on the gonane steroid nucleus had important influences on the promotion activity of Rc, Re, Rd, and Rf on splenic lymphocytes growth. Microcalorimetry can be used as a useful tool for determining the activity and studying the quantity–activity relationship of drugs on cell.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Xiao Yonghou
,
Yan Weifan
,
Yuan Shuanggui
,
Xu Yanbing
,
He Janjun
,
Pan Wiangyan
, and
Li Yingjun

Abstract  

230Ra and its daughter 230Ac were produced by the reaction of 60 MeV/u 18O with ThO2. Using 133Ba, 224Ra and 212Pb–212Bi as tracers, 0.1M NH4EDTA–0.3M NH4-acetate solution as eluent, the relationship between pH and elution peaks, and the influence of the amount of Ba2+ carrier on the elution curve in cation exchange procedures were tested. Based on the results of conditional experiments, a procedure suitable for isolation of radium from the ThO2 irradiated with 60 MeV/u 18O beam was developed. The results demonstrated that the decontamination effectiveness for main reaction products, specially for barium, was satisfactory.

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Abstract  

Barium isotopes were produced by 60 MeV/u 18O ion bombardment of natural uranium via 238U (18O, X) reactions. Ba sources were prepared by radiochemical separation, and measured by a HPGe detector. The cumulative cross sections were obtained by analysis of measured time sequence g-ray spectra. A double peak phenomenon in Ba isotope distribution was observed.

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