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A high-performance thin-layer chromatography (HPTLC) method for the analysis of seven fructooligosaccharides (FOS, DP3-9) in Morinda officinalis How. (M. officinalis) and Arctium lappa Linn. (A. lappa) has been established. The chromatographic analysis was developed twice with a mobile phase consisting of n-butanol-isopropanol-water-acetic acid in volume composition 7:5:2:1 and obtained on silica gel 60 plate. The chromatograms were visualized with 1-naphthol-sulfuric acid reagent. Densitometric detection was performed in visible light at 585 nm for seven FOS. The analytical range was set as 131–1050 ng for FOS. Calibration was linear within the selected range (R 2 > 0.9901). The developed method was applied for the simultaneous determination of seven FOS in M. officinalis and A. lappa. The results indicated that the contents of FOS are variant in different M. officinalis samples, but constant in different A. lappa samples. This HPTLC method was found to be simple, stable, and reproducible. Hence, the developed HPTLC method would be an important tool for the quality control of FOS in medicinal plants.

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Abstract  

This study characterized the removal of strontium from an aqueous solution via co-precipitation followed by microfiltration (CPMF) on a lab-scale. Sodium carbonate was used as the precipitating agent. Ferric chloride was added to a settler at a dosage of 20 mg/L to improve strontium removal, and it was added to a membrane separator at a dosage of 10 mg/L to reduce membrane fouling. The concentration of strontium in the raw water used in this study was about 5 mg/L. In two intermittent tests, where dosages of sodium carbonate were 2000 mg/L and 1000 mg/L, the mean decontamination factors (DFs) were 237 and 158 and the mean concentration factors (CFs) were 288 and 462, respectively. Although the mean DF value was lower when the sodium carbonate dosage was 1000 mg/L instead of 2000 mg/L, the rate at which the specific flux (SF) of the membrane declined decreased as the amount of the effluent treated increased. The problem of strontium release at the beginning of the operation was controlled by a continuous test in which the dosage of sodium carbonate still was 1000 mg/L and the other parameters were the same as in the other tests. The results showed that the mean DF and CF were 157 and 480, respectively.

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A double-development TLC method has been developed for simultaneous qualitative and quantitative analysis of hydrophilic and lipophilic constituents of Salvia miltiorrhiza (Danshen). The optimized mobile phases dichloromethane-ethyl acetate-formic acid 22:24:10 (ν/ν) and petroleum ether-ethyl acetate-cyclohexane 25:11:14 (ν/ν) were used for the double development on nano-silica gel 60F254 plates. Their characteristic TLC profiles were observed under UV light at 254 and 365 nm and the bands were then revealed by reaction with 5% H2SO4 in EtOH. Quantification of twelve compounds was achieved by densitometry at 260 or 290 nm, with reference at 400 nm. Linearity was quite good (R 2 > 0.99) within the ranges tested. This method could be used for quality control of Danshen.

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Abstract  

The water-solubilization of metallofullerenes is important for their potential applications, but their formation processes are still not clear, and the formation yield is uncontrollable. In this paper, we quantitatively studied the water-solubilizing process of Gd@C82 with hydroxylation reaction using ICP-MASS techniques. For the first time, it was found that the formation yield of the multihydroxylated Gd@C82 is declined quickly with the break up of carbon cage of Gd@C82 in the hydroxylated processes. The observation revealed a way to control the hydroxylation processes and increase the formation yield.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Jun Tang
,
Gengmei Xing
,
Hui Yuan
,
Xingfa Gao
,
Long Jing
,
Shukuan Wang
,
Yue Cheng
, and
Yuliang Zhao

Abstract  

The electronic properties of the metal atoms encaged in a fullerence cage were investigated using synchrotron X-ray photoelectron spectroscopy. Systematic variations in photoemission of valence band of Gd@C82, Gd@C82(OH)12, and Gd@C82(OH)22 were observed in Gd 5p levels. The results suggest that the electronic properties of the inner metal atom can be efficiently modulated by surface chemistry of the fullerene cage.

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Abstract

A rapid and simple method for the determination of stearic acid and 12-hydroxystearic acid in PEG-60 hydrogenated castor oil by high performance liquid chromatography with evaporative light scattering detection was established. The oil sample was first pretreated by alkaline hydrolysis. The analysis was performed on a Zhongpu Develop XD-C18 column (250 mm × 4.6 mm, 5 µm) with gradient elution of methanol and 1% acetic acid aqueous solution at a flow rate of 1.2 mL·min−1 and a column temperature of 40 °C. The drift tube temperature of the evaporative light scattering detection system was set at 40 °C, and the pressure of carrier gas (N2) was 337 kPa. The regression equation revealed a good linear relation (r = 0.9993–0.9995) during the test ranges (119.1–1190.7 μg·mL−1 for 12-hydroxystearic acid, 10.7–107.4 μg·mL−1 for stearic acid). The detection limits of 12-hydroxystearic acid and stearic acid were 1.1 and 2.5 μg·mL−1, the limits of quantitation were 3.2 and 7.4 μg·mL−1, respectively. And the mean recoveries were 101.5 and 101.0%, the corresponding relative standard deviations (RSDs) were 2.1 and 2.8%, respectively. The RSDs corresponding to repeatability (n = 6) were both less than 1.7% in terms of precision. As to the stability, the test results remained stable after 8 h at room temperature (RSDs were both less than 2.6%). The developed method showed high sensitivity, recovery, repeatability and stability, which indicated that the method could be applied as a quality evaluation method for the determination of stearic acid and 12-hydroxyoctadecanoic acid in PEG-60 hydrogenated castor oil.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Yan Chen
,
Zhi-yuan Chang
,
Yong-gang Zhao
,
Ji-long Zhang
,
Jing-huai Li
, and
Fu-jun Shu

Abstract  

An isotope dilution multicollector inductive coupled plasma mass spectrometry (ID-MC-ICP-MS) method for determining age of trace Pu through measuring 241Pu/241Am, 240Pu/236U ratio was established. At the same time, other two methods-α-spectrometry combined with MC-ICP-MS and liquid scintillator combined with α-spectrometry through measuring 241Pu/241Am ratio to determine the age of trace Pu were also studied. The techniques were explored for the age determination of nanogram grade Pu sample on the basis of Pu/Am, Pu/U separation. The ages of two Pu samples—one with known and the other with unknown age—were determined by the three methods. The determined ages by the three methods were all in agreement with the reference value. The established methods for determining the age of trace Pu could be adopted in the verification activities of nuclear safeguards and nuclear arms control.

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Abstract

The antibacterial effect of Curcumin on Staphylococcus aureus growth was evaluated by microcalorimetry. The heat flow power–time curves and nine quantitative parameters of the S. aureus growth were applied to investigate the inhibitory effect with Curcumin. By analyzing these curves and some quantitative parameters using multivariate analytical methods, similarity analysis and principal component analysis, the antibacterial activity of Curcumin on S. aureus could be accurately evaluated from the change of the two main parameters, the second exponential growth rate constant k 2 and the maximum heat flow power P m 2. The main two thermal parameters played more important role in the evaluation: at low concentration (0–10.5 μg mL−1), Curcumin hardly influence the growth of S. aureus, while at high concentration (10.5–43.4 μg mL−1) it could notably inhibit the growth. All these illustrated that the antibacterial activity of Curcumin on S. aureus was enhanced with the increase of the concentration of this compound. This study might provide an useful method and idea accurately evaluate the antibacterial effects of Curcumin, which provides some useful methods for evaluate the nature antibacterial agents.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Kit-leong Cheong
,
Ding-tao Wu
,
De-jun Hu
,
Jing Zhao
,
Kai-yue Cao
,
Chun-feng Qiao
,
Bang-xing Han
, and
Shao-ping Li

Multiple species of ginseng are well-known Chinese medicinal herbs. The glycome of Panax species has various beneficial effects; however, studies related to their systematic profiling are very limited. Therefore, the systematic profiling of the glycome of Panax species was investigated in this study. The sugars from different locations and different species of Panax (Panax ginseng, Panax quinquefolium, and Panax notoginseng) were prepared by microwave-assisted extraction. Free mono- and oligo-saccharides were identified by high-performance thin-layer chromatography (HPTLC). Furthermore, polysaccharides were compared and characterized by using saccharide mapping based on HPTLC analysis. The results showed that the mono- and oligo-saccharide in Panax species were similar, including the glucan and pectin type of polysaccharides in different locations and different species of Panax, respectively. The data are helpful to better understand the glycome of different species of Panax and may contribute to rational usage of polysaccharides from Panax species.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Yong He
,
Rui Ding
,
Hang Liu
,
Xiao Wang
,
Jing-Li Xu
,
Man Feng
,
Yu-Rong Chen
,
Chuan-Min Qi
,
Cheng Peng
,
Zhao-Hui Zhu
,
Yong-Hong Dang
,
Ming Wang
, and
Yun-Chuan Ma

Abstract  

As degradation product of Antineoplaston A10 in vivo, phenylacetyl glutamine showed antitumor activities. According to literatures, we designed and radiosynthesized a phenylacetyl glutamine derivative, which was achieved under a mild reaction condition. Evaluations in vitro and in vivo were performed on tumor bearing mice. Excitingly, the radiochemical purity of (S)-2-((S)-2-(4-(3-fluoropropyl)benzamido)-3-phenylpropanamido)pentanedioic acid ([18F]FBPPA) was 98%, and besides the best radiochemical yield was up to 46%. T/Bl (Tumor/Blood) and T/M (Tumor/Muscle) ratios of [18F]FBPPA at 60 min post injection were 2.33 and 3.51. Meanwhile, it showed satisfied stability in vitro and in vivo, compared with 2-[18F]fluorodeoxyglucose ([18F]FDG). Although [18F]FBPPA deserved further studies to make optimizations on its structure, the results revealed it might become a potential PET imaging agent for detecting tumors.

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