紫花地丁中汞的原子荧光法测定

利用还原气化的非色散型装置，以湿法消解的方式，建立了原子荧光测定紫花地丁中痕量汞的测定方法，同时比较了不同玻璃仪器的洗涤方法和不同的定量方法，试验回收率在86．9％－110．8％之间，误差＜8．5％，通过对实际样品的测定，得到了满意的结果。     

肉苁蓉挥发性化学成分分析

报道了用同时蒸馏—萃取法提取肉苁蓉挥发性物质，测得肉苁蓉挥发油的含量为3．5％；利用GC／MS法分离确认出24种化学成分；用峰面积归一化法得出各化学成分在挥发油中的相对百分含量，其中主要成分为丁香酚，占总挥发油的83．60％；又用单离子法分离出丁香酚，并用IR，EI-MS法对其进行分析确认。     

车前草的微量元素含量分析

用电感耦合等离子体发射光谱法测定了湛江地区的车前草中微量元素的含量,发现其Ca、Mn、Zn、Fe、Mg、P、Cu等元素的含量都比较丰富,并讨论了这些有益元素与人体健康的关系。     

Determination and Differentiation of Two Seemingly Identical Medicinal Herbs by Capillary Electrophoresis with Electrochemical Detection

A high-performance capillary electrophoresis with electrochemical detection (CE-ED) method has been employed for the determination of six bioactive ingredients in traditional Chinese herbs, Herba cepbalanoplosis segeti and Herba cirsii japonici. The effects of several factors such as the acidity and concentration of running buffer, the separation voltage, the applied potential and the injection time on CE-ED were investigated. Under the optimum conditions, the six analytes could be well separated within 21 min in a 75 cm length capillary at the separation voltage of 15 kV in a 50 mmol L^–1 borax running buffer (pH 8.4). A 300 m diameter carbon disk electrode was used as the working electrode positioned carefully opposite the outlet of the capillary in a wall-jet configuration at potential of +950 mV (vs. SCE). Good linear relationship was established between peak current and concentration of analytes over two orders of magnitude with detection limits (S/N=3) ranged from 1.5×10^–7 to 6.0×10^–7 g mL^–1 for all six analytes. This proposed method has been successfully applied for the analysis of traditional Chinese herbs after a relatively simple extraction procedure, further on, for the differentiation of these above two seemingly identical herbs based on their electropherograms or characteristic electrochemical profiles.     

中国车前草挥发性化学成分分析

用同时蒸馏 萃取装置(SDE)提取中国车前草的挥发性物质,测得车前草挥发油质量分数为2.79%,用GC MS法从车前草的挥发油中分离确认出20种化学成分,占挥发油总量的95.08%。用峰面积归一化法通过化学工作站数据处理系统得出各化学成分在挥发油中的质量分数。     

Fabrication of graphene/poly(methyl methacrylate) composite electrode for capillary electrophoretic determination of bioactive constituents in Herba Geranii

This report describes the development and application of a novel graphene/poly(methyl methacrylate) composite electrode as a sensitive amperometric detector of capillary electrophoresis. The composite electrode was fabricated on the basis of the in situ polymerization of a mixture of graphene and prepolymerized methyl methacrylate in the microchannel of a piece of fused silica capillary under heat. SEM, XRD and FT-IR offered insights into the nature of the composite. The results indicated that graphenes were well dispersed in the composite to form an interconnected conducting network. The performance of this unique graphene-based detector has been demonstrated by separating and detecting seven naturally occurring phenolic compounds in Herba Geranii in combination with capillary electrophoresis. The graphene-based detector offered significantly lower operating potentials, substantially enhanced signal-to-noise characteristics, and lower expense of operation. The simplicity and significant performance exhibited by the graphene/poly(methyl methacrylate) composite electrode also indicate great promise for microchip CE, flowing injection analysis, and other microfluidic analysis systems.     

Development and Validation of a LC–ESI–MS Assay for Determination of Icariin in Rat Plasma after Administration of Herba Epimedii

This paper reports a sensitive, specific, and stable chromatographic procedure with selective detection (electrospray mass spectrometry in selected-ion-monitoring mode) combined with simple and efficient sample preparation for determination of icariin in rat plasma after administration of Herba Epimedii. Separation of the analyte, possible endogenous compounds, and constituents of Herba Epimedii were accomplished on a 250 mm × 2.0 mm i.d. C₁₈ column by use of a rapid gradient. Ionization of icariin and clarithromycin (internal standard) was achieved by use of the electrospray interface in positive-ion mode. Conditions such as ionization mode, type of organic modifier, eluent additives, and Q-array potential were optimized to achieve good sensitivity and specificity of icariin detection. Response was a linear function of concentration over the range 0.2–20 ng mL⁻¹. The method is accurate and precise; within-batch and between-batch precision (CV) are <15%, and accuracy (RE) is better than ±15%. The method can be used for analysis of icariin in plasma after administration of Herba Epimedii or of traditional Chinese medicinal preparations containing Herba Epimedii.     

Exploration of a ternary deep eutectic solvent of methyltriphenylphosphonium bromide/chalcone/formic acid for the selective recognition of rutin and quercetin in Herba Artemisiae Scopariae

Methyltriphenylphosphonium bromide/chalcone/formic acid, a green ternary deep eutectic solvent, was applied as a functional monomer and dummy template simultaneously in the synthesis of a new molecularly imprinted polymer. Ternary deep eutectic solvent based molecularly imprinted polymers are used as a solid‐phase extraction sorbent in the separation and purification of rutin and quercetin from Herba Artemisiae Scopariae combined with high‐performance liquid chromatography. Fourier transform infrared spectroscopy and field‐emission scanning electron microscopy were applied to characterize the deep eutectic solvent based molecularly imprinted polymers synthesized using different molar ratios of chalcone. The static and competitive adsorption tests were performed to examine the recognition ability of the molecularly imprinted polymers to rutin and quercetin. The ternary deep eutectic solvent consisting of formic acid/chalcone/methyltriphenylphosphonium bromide (1:0.05:0.5) had the best molecular recognition effect. After optimization of the washing solvents (methanol/water, 1:9) and eluting solvents (acetonitrile/acetic acid, 9:1), a reliable analytical method was developed for strong recognition towards rutin and quercetin in Herba Artemisiae Scopariae with satisfactory extraction recoveries (rutin: 92.48%, quercetin: 94.23%). Overall, the chalcone ternary deep eutectic solvent‐based molecularly imprinted polymer coupled with solid‐phase extraction is an effective method for the selective purification of multiple bioactive compounds in complex samples.     

Qualitative and quantitative analysis of chemical constituents in Ardisiae Japonicae Herba

Ardisiae Japonicae Herba is a well‐known traditional Chinese medicine for the treatment of bronchitis conjunctivitis, pneumonia, and trauma. In this work, a high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry method was first established for the separation and structural identification of the chemical constituents in Ardisiae Japonicae Herba. A total of 15 compounds including coumarins, flavonoid glycosides, and catechins were identified or tentatively characterized based on their chromatographic behaviors and mass spectral fragmentation and by comparisons with the reference standards. Furthermore, a simple high‐performance liquid chromatography with diode array detection method was developed for the simultaneous determination of five major constituents. Results obtained from method validation, including linearity, precision, repeatability, stability, and recovery, showed that the established method was reliable and accurate. Bergenin and quercitrin were found to be the most abundant constituents and could be served as chemical markers for quality control of Ardisiae Japonicae Herba.