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This study aims to develop and validate a high-performance size-exclusion chromatography (HPSEC) method to determine the amount of polymer in cefmetazole sodium for injection and to compare this method with gel chromatography. A Zenix SEC-150 column was used with the mobile phase of phosphate buffer solution (pH 7.0; 0.01 M)—acetonitrile (90:10 v/v) at a flow rate of 0.8 mL min−1 and a detection wavelength of 240 nm. The polymer was quantified by an external standard method with self-control, and the amount was expressed by the percentage of cefmetazole. The HPSEC method was validated for specificity, linearity, and precision. The chromatographic conditions, chromatographic performances, sensitivity, linearity, and precision of the developed HPSEC method and gel chromatography were compared, and both methods were subsequently used to determine the amount of polymer from seven batches of samples. The HPSEC method was fully validated. The time of isocratic elution for sample assay was less than 14 min. The results of comparison indicate that the developed HPSEC method was superior to gel chromatography. The Student t test results also showed significant difference in the amount of polymer from the samples obtained by the two methods. Thus, the HPSEC method with two obvious advantages, the superior sensitivity and a shorter analysis time, is more suitable for determination of polymer amount in cefmetazole sodium for injection to control the quality of the product.

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Abstract  

Research on extracted 90Y with di(2-ethylhexyl) orthophosphoric acid (P204) in lipiodol for liver cancer was made to evaluate the stability of extracted 90Y with P204 in lipiodol (90Y-P204-lipiodol) in serum of newly-born cattle and human’s blood. At first, P204 (extractant) was dissolved in lipiodol (organic phase). Secondly, 90Y was extracted to organic phase after adding 90Y solution into test tube with P204 and lipiodol in it. The extracting efficiency with 0.01 mol/l P204 could reach 99.4%. The stability of 90Y-P204-lipiodol has been experimented in physiological saline solution as preparation for further stability experiment. The result indicated that the extracted 90Y lost 0.02%–0.36% in physiological saline solution. The results of further stability experiment showed that loss efficiencies of extracted 90Y after adding newly-born cattle serum 1 hour, 1 day, 3 and 7 days are 3.38%, 3.12%, 4.29% and 6.62%, respectively, and loss efficiencies of extracted 90Y after adding human’s blood 1 hour, 1 day, 3 and 7 days are 2.55%, 5.91%, 7.88% and 5.63%, respectively. Our data also indicated that 90Y is the most possible radioisotope for being extracted with P204 in lipiodol to treat hepatocellular carcinoma, particularly in cases of unresectable liver tumors, since 90Y is available from several commercial sources in clinical quality. We conclude that the stability of 90Y-P204-lipiodol tested with newly-born cattle serum and human’s blood attained great results. 90Y-P204-lipiodol is a kind of potential and exciting pharmaceutical in inerventional therapy for liver cancer and we can carry on the further animal test and clinical trial.

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Abstract  

A novel double -diketone 1,6-bis(1-phenyl-3-methyl-5-oxo-pyrazol-4-yl) hexanedione-[1,6] (BPMOPH) was further studied on its coordination compounds with uranium and thorium, respectively. The IR, UV, and1H-NMR spectra were examined, and the proposed structure is discussed.

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New hexamethylenetetramine complexes of antimony and bismuth trichloride were synthesized through a solid phase reaction of hexamethylenetetramine and antimony or bismuth trichloride. The formula of the complex is MCl3(C6H12N4)2⋅H2O (M=Sb, Bi).The crystal structure of the complexes belongs to monoclinic system and the lattice parameters: a=1.249 nm, b=1.4583 nm, c=1.6780 nm andβ=91.78 for SbCl3(C6H12N4)2⋅H2O and a=1.3250 nm, b=1.3889 nm, c=1.7449 nm and β=98.94 for BiCl3(C6H12N4)2⋅H2O. Far-infrared spectra reveal that the antimony or bismuth ion is coordinated by the nitrogen atom of the hexamethylenetetramine. The thermal analysis also demonstrates the complex formation between the antimony or bismuth ion and hexamethylenetetramine. The intermediate and final residues in the thermal decomposition process have been analyzed to check the pyrolysis reaction.

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A solid complex Eu(C5H8NS2)3(C12H8N2) has been obtained from reaction of hydrous europium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen⋅H2O) in absolute ethanol. IR spectrum of the complex indicated that Eu3+ in the complex coordinated with sulfur atoms from the APDC and nitrogen atoms from the o-phen. TG-DTG investigation provided the evidence that the title complex was decomposed into EuS. The enthalpy change of the reaction of formation of the complex in ethanol, Δr H m θ(l), as –22.2140.081 kJ mol–1, and the molar heat capacity of the complex, c m, as 61.6760.651 J mol–1 K–1, at 298.15 K were determined by an RD-496 III type microcalorimeter. The enthalpy change of the reaction of formation of the complex in solid, Δr H m θ(s), was calculated as 54.5270.314 kJ mol–1 through a thermochemistry cycle. Based on the thermodynamics and kinetics on the reaction of formation of the complex in ethanol at different temperatures, fundamental parameters, including the activation enthalpy (ΔH θ), the activation entropy (ΔS θ), the activation free energy (ΔG θ), the apparent reaction rate constant (k), the apparent activation energy (E), the pre-exponential constant (A) and the reaction order (n), were obtained. The constant-volume combustion energy of the complex, Δc U, was determined as –16937.889.79 kJ mol–1 by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δc H m θ, and standard enthalpy of formation, Δf H m θ, were calculated to be –16953.379.79 and –1708.2310.69 kJ mol–1, respectively.

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The aim of this paper is to consider using effective natural minerals in studying the retardation and migration of radium under the influence of groundwater in the far-field of a radioactive waste repository. The properties of adsorbing radium by minerals are studied by adopting the static and dynamic adsorption method. Preliminary experimental results give confidence in the validity of using Maifanshih and barite to adsorb radium in water and to serve as effective retarding materials in radioactive waste repositories, their Kd values being 3815 and 2955, respectively. The study on a certain number of conditions of adsorbing radium by the promissing material Maifanshih is reported for the first time. The mechanism of radium adsorption has been discussed and modeling of migration of radium in the minerals has been presented to establish a rational basis for the longterm prediction required for safety assessment of underground disposal of radioactive waste.

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An efficient and sensitive analytical method based on precolumn derivatization and gas chromatography—mass spectrometry—selected ion monitoring (GC—MS—SIM) was proposed and validated for analysis of two cembrenediols (CBDs) which are α-cembrenediol and β-cembrenediol in tobacco samples. CBDs in tobacco samples were extracted by sonication with 50 mL dichloromethane for 10 min before derivatized with 2:3 (v/v) bis(trimethylsilyl)trifluoroacetamide (BSTFA)—pyridine at 20 °C for 100 min. CBDs’ level in tobacco samples was analyzed by GC—MS—SIM and quantified by the internal standard method. The linear range for α-CBD and β-CBD was 13.6–554.6 μg mL−1 and 4.11–162.6 μg mL−1, and the correlation coefficients of both were 0.9998. The limit of detection (LOD) and limit of quantification (LOQ) of α-cembrenediol and β-cembrenediol were 0.40 μg g−1 and 1.34 μg g−1, and 0.27 μg g−1 and 0.90 μg g−1, respectively. Average recoveries of α-CBD and β-CBD were 94.4–99.9% and 91.9–98.2% while the relative standard deviations (RSDs, n = 5) were ranged from 2.67 to 5.6% and 2.04 to 4.22%, respectively. This proposed analytical method has been successfully applied to analyze CBDs in tobacco samples.

Open access

Aegilops sharonensis (Sharon goatgrass) is a valuable source of novel high molecular weight glutenin subunits, resistance to wheat rust, powdery mildew, and insect pests. In this study, we successfully hybridized Ae. sharonensis as the pollen parent to common wheat and obtained backcross derivatives. F1 intergeneric hybrids were verified using morphological observation and cytological and molecular analyses. The phenotypes of the hybrid plants were intermediate between Ae. sharonensis and common wheat. Observations of mitosis in root tip cells and meiosis in pollen mother cells revealed that the F1 hybrids possessed 28 chromosomes. Chromosome pairing at metaphase I of the pollen mother cells in the F1 hybrid plants was low, and the meiotic configuration was 25.94 I + 1.03 II (rod). Two pairs of primers were screened out from 150 simple sequence repeat markers, and primer WMC634 was used to identified the presence of the genome of Ae. sharonensis. Sequencing results showed that the F1 hybrids contained the Ssh genome of Ae. sharonensis. The sodium dodecyl sulfate polyacrylamide gel electrophoresis profile showed that the alien high molecular weight glutenin subunits of Ae. sharonensis were transferred into the F1 and backcross derivatives. The new wheat-Ae. sharonensis derivatives that we have produced will be valuable for increasing resistance to various diseases of wheat and for improving the quality of bread wheat.

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To study the development of starch granules in polyploid wheats, we investigated the expression of starch synthetic genes between the synthetic hexaploid wheat SHW-L1, its parents T. turgidum AS2255 and diploid Ae. tauschii AS60. The synthetic hexaploid wheat SHW-L1 showed significantly higher starch content and grain weight than its parents. Scanning electron microscopy (SEM) showed that SHW-L1 rapidly developed starch granules than AS2255 and AS60. The amount of B-type granule in AS60 was less than that in SHW-L1 and AS2255. RT-qPCR result showed that the starch synthetic genes AGPLSU1, AGPLSU2, AGPSSU1, AGPSSU2, GBSSI, SSIII, PHO1 and PHO2 expressed at earlier stages with larger quantity in SHW-L1 than in its parents during wheat grain development. The expression of the above mentioned genes in AS60 was slower than in SHW-L1 and AS2255. The expression pattern of starch synthase genes was also associated with the grain weight and starch content in all three genotypes. The results suggested that the synthetic hexaploid wheat inherited the pattern of starch granule development and starch synthase gene expression from tetraploid parent. The results suggest that tetraploid wheat could plays more important role for starch quality improvement in hexaploid wheat.

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Journal of Thermal Analysis and Calorimetry
Authors: Z. Xiao, D. Liu, C. Wang, Z. Cao, X. Zhan, Z. Yin, Q. Chen, H. Liu, F. Xu, and L. Sun

Abstract  

The effect of mechanical alloying on Zn-Sb alloy system is investigated with X-ray diffraction (XRD), laser grain size analysis and differential scanning calorimetry (DSC) respectively. The results of laser particle size analysis shows that the particle size decreases with increasing of the grinding time between 0 and 24 h. XRD and DSC results indicate that longer the grinding time of Zn-Sb is, the more content of Zn4Sb3 become in the product in this process.

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