Simultaneous determination of isoflavonoids in huangqi gegen herbal pair and its markted formulations by RP-HPLC-UV

Jianping Deng, Yuanwen Wen, Yifei Wang, Zhiping Wang

Abstract: A new simple and efficient RP-HPLC-UV method was developed for the simultaneous analysis of isoflavonoids in Huangqi Gegen herbal pair and its marketed formulations. Effective chromatographic separation of ten active components was achieved on a Kromasil C18 column (4.6×250 mm, i.d.; 5 μm) with gradient elution of methanol and 0.2% formic acid aqueous solution at a flow rate of 1.0 mL/min in 60 min. Detection was performed at 250nm. The validation of the method included tests of linearity, sensitivity, precision, repeatability, stability and accuracy. All calibration curves showed good linear regression (r>0.999) within test ranges. The established method showed good precision and accuracy with overall intra-day and inter-day variations of 0.77-1.81 % and 1.38-2.47 %, and overall recoveries of 96.64-103.96 % for the compounds analyzed. The developed method was successfully applied for the quantitative analysis of constituents in Huangqi gegen and its marketed formulations.

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Cluster Analysis for Dependent Network Sequences

Liang Wang, Qi Zhang, Xinmin Li, Shunyao Wu

Abstract: Dynamic complex network has now become a major field of research and cluster analysis is a common tool to extract network structure. Previous articles on network clustering mostly supposed that observations are conditionally independent. However, we construct a novel model which combines the stochastic block model, the hidden structure in Markov process and the autoregressive model to relax this assumption. We also propose relative statistical inference and VEM algorithm to calculate the parameters iteratively. Finally, the Monte Carlo simulations are performed well, which shows the consistency and robustness of the work.

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Preparation and evaluation of thermosensitive diclofenac sodium in-situ gel

Jialing Dai, Ruoyu Zhang, Yang Gao, Zichen Li, Guodong Ma, Yong Sun

Abstract: Diclofenac sodium (DS), as a good non-steroidal anti-inflammatory drug, was an excellent drug for treating acute pain such as arthritis rheumatism. However, there were many problems in the current preparations: poor targeting of oral drugs, large toxic and side effects of drugs, and the therapeutic effect was not very satisfactory. This study aimed at the above problems to improve the efficiency of DS: using poloxamer 407 (P407) and sodium alginate nanoscale spinning as gel skeleton and DS as model drug to prepare a thermosensitive in-situ gel for joint cavity injection. we choose 17% P407 thermosensitive gel (the gelation temperature was 30.8℃, the gelation time was 1min30s) to ensure the gel could be formed at human body temperature. And it was corrosed completely at the ninth day. The gelation temperature reduced from 30.8℃ to 28℃ and was still completely corrosed at the ninth day after 17% P407 thermosensitive gel loading DS. We developed the method of HPLC to determine the content of DS. With the concentration of sodium alginate increased, the rate of DS release from the sodium alginate-DS-P407 thermosensitive gel slowed down and the corrosion of sodium alginate-DS-P407 thermosensitive gel slowed down too. It was expected to prolong the efficacy of DS in situ gel in vivo.

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Anti-hepatocarcinoma effectsof puerarin-nanostructured lipid carriers against human HepG2 cells

Zicong Wu, Zhihui Li, Yifei Wang, Zhiping Wang

Abstract: Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Puerarin (Pue), amajor active ingredient in the traditional Chinese medicine Gegen, has a widerange of pharmacological properties and isconsidered to have anti-hepatocarcinomaeffects. However its low oral bioavailability restrictsits wide application. In this report, Pue loaded nanostructured lipidcarriers (Pue-NLC) was prepared by hot melting and then high pressure homogenization technique. The in vitro anti-hepatocarcinoma effects of Pue-NLC relative to efficacy of bulk Pue were evaluated. The particle size and zeta potential of Pue-NLC were 191.3 nm and −17.9 mV, respectively. MTT assay showed that Pue-NLCeffectively inhibited the proliferation of HepG2 cells, and the corresponding IC50 values of Pue-NLC and bulk Pue were2.98 and 5.73 µg/ml.These results suggest that the delivery of Pue-NLC is a promising approach for treating tumors..

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