Optimising resolution for a preparative separation of Chinese herbal medicine using a surrogate model sample system

This paper builds on previous modelling research with short single layer columns to develop rapid methods for optimising high-performance counter-current chromatography at constant stationary phase retention. Benzyl alcohol and p-cresol are used as model compounds to rapidly optimise first flow and then rotational speed operating conditions at a preparative scale with long columns for a given phase system using a Dynamic Extractions Midi-DE centrifuge. The transfer to a high value extract such as the crude ethanol extract of Chinese herbal medicine Millettia pachycarpa Benth. is then demonstrated and validated using the same phase system. The results show that constant stationary phase modelling of flow and speed with long multilayer columns works well as a cheap, quick and effective method of optimising operating conditions for the chosen phase system—hexane–ethyl acetate–methanol–water (1:0.8:1:0.6, v/v). Optimum conditions for resolution were a flow of 20 ml/min and speed of 1200 rpm, but for throughput were 80 ml/min at the same speed. The results show that 80 ml/min gave the best throughputs for tephrosin (518 mg/h), pyranoisoflavone (47.2 mg/h) and dehydrodeguelin (10.4 mg/h), whereas for deguelin (100.5 mg/h), the best flow rate was 40 ml/min.     

Data Preprocessing for Chromatographic Fingerprint of Herbal Medicine with Chemometric Approaches

Abstract

Recently, the fingerprinting approach using chromatography has become one of the most potent tools for quality assessment of herbal medicine. Due to the complexity of the chromatographic fingerprint and the irreproducibility of chromatographic instruments and experimental conditions, several chemometric approaches such as variance analysis, peak alignment, correlation analysis, and pattern recognition were employed to deal with the chromatographic fingerprint in this work. To facilitate the data preprocessing, a software named Computer Aided Similarity Evaluation (CASE) was also developed. All programs of chemometric algorithms for CASE were coded in MATLAB5.3 based on Windows. Data loading, removing, cutting, smoothing, compressing, background and retention time shift correction, normalization, peak identification and matching, variation determination of common peaks/regions, similarity comparison, sample classification, and other data processes associated with the chromatographic fingerprint were investigated in this software. The case study of high pressure liquid chromatographic HPLC fingerprints of 50 Rhizoma chuanxiong samples from different sources demonstrated that the chemometric approaches investigated in this work were reliable and user friendly for data preprocessing of chromatographic fingerprints of herbal medicines for quality assessment.     

Simultaneous Determination of Inorganic Cations and Anion in Medical Electrolytes by Capillary Electrophoresis

Abstract

Capillary electrophoresis (CE) was developed in order to effect rapid, specific determination of potassium, calcium, sodium, and magnesium. Ions (4 cations, 1 anion) were measured continuously via shifting of samples from the inlet electrode to the outlet electrode; moreover, samples were subjected to indirect and direct ultraviolet (UV) techniques, respectively. For the measurement of cations, imidazole (5 mM) functioned as a UV absorber of indirect detection at 214 nm. Consequently, anions can be measured directly by UV at 214 nm. Separation times of cations and Cl^? anions were 10 min and 2 min, respectively; the detection limit of each ion (chloride, magnesium, sodium, calcium, and potassium) was 0.1 µmol/L. This approach is very simple; additionally, measurement time is extremely short. As a result, the proposed method is suitable for routine assay of electrolytes in pharmaceutical preparations.     

Highly Selective Potentiometric Sensor for Determining Phenazopyridine Hydrochloride in Biological Fluids Using N,N′-(Pyromellitoyl)-bis-L-tyrosine Dimethyl Ester

A new membrane selective electrode based on the potentiometric method was developed for the determination of phenazopyridine. The membrane signal is based on the interaction of N,N′-(pyromellitoyl)-bis-L-tyrosine dimethyl ester with phenazopyridine. The sensor displays a linear response with a slope of 61.1 mV decade^?1 for phenazopyridine concentrations in the range of 1.0 × 10^?2–1.0 × 10^?5 mol L^?1 and with detection limit of 8.0 × 10^?6 mol L^?1 of phenazopyridine. The electrode enjoys a fast response time. Application of this potentiometric sensor for phenazopyridine determination in pharmaceuticals, urine, and blood serum samples is reported without any special pretreatment required.     

补阴类中草药中四种微量元素的测定

为测定补阴类中药中Zn、Fe、Cu、Mn 4种微量元素的含量,采用V(HNO3)+V(HClO4)=4+1混合酸常压微沸条件下消解样品,运用火焰原子吸收光谱法测定了补阴类中草药女贞子、桑寄生、木蝴蝶中Zn、Fe、Cu、Mn 4种微量元素的含量。结果表明,3种中草药Fe含量最高,Zn、Mn次之,Cu含量最低。该法的加标回收率在95.2%～105.4%之间,RSD<2.000 0%,具有良好的准确度和精确度。结果为这类中药保健作用的进一步开发提供了参考。     

新型吡唑联吡咯类杂环化合物的合成及杀菌活性

为寻找具有更高生物活性、更环保的新农药杀菌剂,基于杀菌剂氟咯菌腈设计并合成了10个新型吡唑联吡咯类杂环化合物,以吡唑环代替氟咯菌腈上原有的苯环,以期提高其杀菌活性.采用1H NMR,FTIR,单晶X射线衍射、元素分析和熔点测定等测试手段对目标化合物及其中间体的结构进行了表征与确认,并通过挥发法培养得到了6个目标化合物的单晶.还对其中6个化合物进行了生物活性测试,测试结果表明各化合物对水稻纹枯病、黄瓜灰霉病、黄瓜霜霉病均表现出一定的抑菌效果,可作为先导化合物对其结构进行深入的研究,为新农药杀菌剂的开发提供了理论支持.     

论卤盐养生（10）

卤盐（包括食盐）是中国矿物药的重要组成部分。从文化价值、临床应用和情志调摄3个方面诠释了卤盐的养生学意义,并全面、详细地阐述了食盐对中国古代文化的四大贡献、6种盐类的现代临床应用价值以及盐湖旅游的6项要素;列举了160多个盐湖卤水的主要化学成分、矿化度或微量元素;摘录了论述卤盐主治功用的古今文献。本文分期刊出。     

示波极谱法测定保健药品中的褪黑激素

褪黑激素与HNO3在室温下发生硝基化反应生成褪黑激素的硝基化合物,加NH3·H2O终止反应并用甲酸 甲酸钠缓冲液控制反应液pH3,在原点电位-0.20V(vs.SCE),测量-0.50V处的二阶导数峰高。方法检出限为1μg/L,线性范围为1μg/L～200μg/L,相对标准偏差为2.6%～8.0%,加标回收率为92 0%～110 0%,测定结果与高效液相色谱法进行比较,无显著性差异。     

氢化物原子荧光法测定中草药中痕量铅

提出了以重铬酸钾为氧化剂、碱性铁氰化钾为络合剂 ,在柠檬酸介质中进行铅的氢化物发生反应。采用断续流动氢化物发生器 ,对原子荧光法测定痕量铅的条件进行了系统研究 ,并考察了共存元素的干扰情况。在最佳测试条件下 ,测得铅的检出限 (3σ)为 0 .19μg·L- 1,相对标准偏差为 0 .92 %。应用于中草药中痕量铅的测定 ,回收率为 95 .1%～ 10 9.5 % ,结果满意     

Synthesis,Crystal Structure and Biological Activity of 2-(3,4-Dichloroisothiazol-5-yl)-4-(trifluoromethyl)-4,5-dihydrothiazol-4-yl-3-methylbenzoate

The title compound diethyl 2-(3,4-dichloroisothiazol-5-yl)-4-(trifluoromethyl)-4,5-dihydrothiazol-4-yl-3-methylbenzoate(C15H9Cl2F3N2O2S2, Mr = 441.26) was prepared from methyl 3,4-dichloroisothiazole-5-carboxylate as the starting material by four steps of reaction. Its structure was characterized by IR, 1H-NMR, 13C-NMR, EA and single-crystal X-ray diffraction. The crystal of the title compound belongs to the monoclinic system, space group P21/c with a = 8.8437(18), b = 16.128(3), c = 12.305(3), β = 91.68(3)o, V = 1754.4(6) 3, Z = 4, Dc = 1.671 g/cm3, μ(Mo Ka) = 0.71073 mm-1, F(000) = 888, R = 0.0384 and w R = 0.0778. Weak π-π interactions occur between the isothiazole rings and phenyl rings of adjacent molecules to form a one-dimensional chain and stabilize the crystal structure. Bioassay indicates that the title compound has good activity against the fungi and TMV tested.