黄芩及其制剂中黄芩素和黄芩甙的

用毛细管区带电泳 -电化学检测法测定了黄芩及其制剂中黄芩素和黄芩甙的含量。研究了电极电位、电解液酸度和浓度、电泳电压及进样时间等对电泳的影响 ,得到了较为优化的测定条件。以直径为300μm的碳圆盘电极为检测电极 ,电极电位为0.90V(vsSCE) ,在100mmol/L硼酸盐缓冲液(pH9.0)中 ,上述两组分在8min内完全分离。黄芩素和黄芩甙浓度与电泳峰电流分别在5.0×10 -7～1.0×10 -3mol/L和1.0×10 -6～1.0×10 -3mol/L范围内呈良好线性 ,检出限分别为2.24×10 -7mol/L和5.48×10 -7mol/L。7次测定分别含5.0×10 -4mol/L黄芩素和黄芩甙试样溶液 ,峰高的相对标准偏差分别为3.53%和4.03%。     

黄芩及其制剂中黄芩素和黄芩甙的毛细管区带电泳—电化学检测

用毛细管区带电泳－电化学检测法测定了黄芩及其制剂中黄芩素和黄芩甙的含量。研究了电极电位、电解液酸度和浓度、电泳电压及进样时间等对电泳的影响,得到了较为优化的测定条件。以直径为300μm的碳圆盘电极为检测电极,电极电位为0.90V(vsSCE),在100mmol/L硼酸盐缓冲液(pH9.0)中,上述两组分在8min内完全分离。黄芩素和黄芩甙浓度与电泳峰电流分别在5.0×10     

双黄连粉针剂中黄芩苷的高效毛细管电泳-电导法测定

建立了双黄连粉针剂中黄芩苷含量测定的高效毛细管电泳电导法;以未涂层融硅毛细管(75μm×50cm)为分离柱,Tris-H3BO3为电泳介质(15mmo1/LTris,1.5mmol/LH3BO3),在18kV、pH85的碱性环境下,柱端电导检测双黄连粉针剂中的黄芩苷含量;重点探讨了缓冲溶液的种类、浓度、分离电压、进样时间对检测的影响;该法的线性范围为10～720mg/L,检出限为2.5mg/L;结果表明该法简便、快速、结果准确,适用于含黄芩苷的制剂含量的测定.     

银黄冲剂中黄芩甙和绿原酸的毛细管电泳分离分析

摘要：用毛细管电泳法分离并测定了银黄冲剂中黄芩甙和绿原酸。以对硝基苯甲酸为内标,未涂层融硅毛细管（50μmi.d.,370μmo.d.,总长47cm,有效分离长度40cm）为分离通道,25mmol/L硼砂缓冲液（pH8.5）为电泳介质,17kPa·s压力进样,25kV恒压电泳,310nm检测。黄芩甙和绿原酸线性范围分别为160～960mg/L(r=0.9993,RSD=1.76％～2.33％）和80～960mg/L（r=0.9989,RSD=1.07％～2.51％）,加入回收率：黄芩甙为（102.09±1     

毛细管电泳测定三精双黄连口服液中的黄芩甙元、黄芩甙、绿原酸和咖啡酸

建立了毛细管电泳法测定中药复方制剂双黄连口恨液中黄芩甙元、黄芩甙、绿原酸和咖啡酸的方法,通过研究缓冲溶液pH和浓度、分离电压、进样时间和有饥添加剂的影响优化了分析条件在优化的条件下,20min内实现了4种物质的良好分离黄芩甙元、黄芩甙、绿原酸和咖啡酸峰高和质量浓度分别在0．05～1．50、0.06～1．20、0．02～0．50和0．02～0．50g／L范围内呈良好线性;俭出限分别为0．015、0．020、0．004、0．004g／L基于迁移时间和峰高的重复性分别为：黄芩甙元,1．70％和3．94％;黄芩甙,1．60％和3．63％;绿原酸,1．60％和2．05％;咖啡酸,1．51％和2．83％通过分析实际样品并做加标回收实验验证了该方法的可行性。     

胶束电动毛细管色谱法测定消糖灵中的优降糖

 以甲氧苄氨嘧啶为内标,采用胶束电动毛细管色谱法分离测定了新药消糖灵中的优降糖。电泳条件：以25 mmol/L硼砂-30 mmol/L十二烷基硫酸钠（pH 9.0）为电泳介质,未涂层石英毛细管（50 μm i.d.×39.5 cm,有效分离长度34.8 cm）为分离通道,压力进样(68.95 kPa.s),17 kV恒压电泳（28 ℃）,检测波长228 nm。优降糖在14 min内与其他成分得到很好分离,且质量浓度为25 mg/L～275 mg/L时,优降糖可进行定量分析,加标回收率为(100.6±1.4)%。方法简便、快速,结果准确,重现性好,可用于优降糖复方制剂的质量控制。     

黄芩甙的极谱催化波研究及应用

在 0 .2 4mol/L混合酸 NaOH(Britton Robinson) (pH 2 .0 ) -8× 1 0 -3 mol/LKIO3 支持电解质中 ,黄芩甙产生一极谱催化波 ,峰电位为 -1 .2 0V(vs.SCE)。该波的一阶导数峰峰电流与黄芩甙浓度在 1×1 0 -7～ 3× 1 0 -6mol/L范围内呈线性关系 (r=0 .9988)。用该法测定了三黄片中黄芩甙的含量。该催化波是有机化合物极谱催化波的一种新类型—缔合 /平行催化波。IO-3 有双重作用 :( 1 )IO-3 作为配位体与吸附在电极表面的质子化黄芩甙形成离子对缔合物 ,引起峰电位的负移 ;( 2 )IO-3 及其还原中间体作为氧化剂氧化黄芩甙羰基经单电子单质子还原产生的自由基 ,产生了极谱催化波     

桂林西瓜霜喷剂中盐酸小檗碱、苦参碱与黄芩苷的毛细管电泳测定

建立了毛细管电泳法同时测定中药复方制剂桂林西瓜霜喷剂中盐酸小檗碱、苦参碱和黄芩苷含量的分析方法.通过研究缓冲溶液的酸度和浓度、工作电压、进样时间和有机添加剂的影响,优化了分析条件,以20 mmol/L硼砂缓冲溶液(含体积分数10%乙醇)作电解质(pH 9.0),于206 nm紫外检测.在优化的条件下,3种被测物在7 min内得到了良好分离,盐酸小檗碱、苦参碱和黄芩苷的峰面积和质量浓度分别在4.0 ～160 mg/L、14 ～420 mg/L和25～600 mg/L范围内呈良好线性,检出限分别为1.0、6.0和8.0 mg/L(S/N=3).此方法快速、简便,已成功地用于实际样品的分析.     

高效液相色谱-二极管阵列检测-电化学检测联用技术同时测定三精双黄连口服液中的4种化合物

建立了应用高效液相色谱-二极管阵列检测-电化学检测(HPLC-DAD-ECD)联用技术同时测定三精双黄连口服液中的绿原酸、咖啡酸、黄芩甙和木樨草素的方法。以Zorbax SB-C18柱(150 mm×4.6 mm i.d., 5.0 μm)为色谱柱,柱温为30 ℃，流动相为(A)甲醇和(B)甲醇-水-冰醋酸(体积比为50∶50∶1),其梯度洗脱程序为2%A3 min3%A12 min25%A5 min80%A。流速为0.8 mL/min。二极管阵列检测波长为275 nm。电化学单安培检测器的工作电压为0.7 V。在上述条件下实现了绿原酸、咖啡酸、黄芩甙和木樨草素的分离检测。上述4种化合物的回收率为96.6%～99.6%,相对标准偏差(RSD)为2.5%～4.1%,检测限依次为1,0.2,9和7 mg/L。该方法简便、快速,重现性和准确度较好,可作为测定双黄连口服液中绿原酸、咖啡酸、黄芩甙和木樨草素的有效方法。     

清开灵注射液中黄芩苷含量的微乳液相色谱法测定

建立了微乳液相色谱(MELC)测定中药复方制剂清开灵注射液中黄芩苷含量的分析方法,并考察了微乳流动相的组成及pH值等影响因素.最佳条件为:采用Hypersil BDS C18 5 μm(4.6 mm×150 mm)色谱柱,柱温30 ℃,以3%十六烷基三甲基溴化铵-0.8%乙酸乙酯-7%乙腈-0.01 mol/L 四丁基溴化铵(磷酸调pH至3.0)为流动相,检测波长276 nm.对照品和样品均用70%甲醇处理.结果表明,黄芩苷的线性范围为25 ～100 mg/L,相关系数r=0.999 9.精密度实验和稳定性实验的RSD分别为1.0%(n=6)和0.50%(n=5),平均加标回收率和RSD值(n=6)分别为99%、1.9%.市售9批样品中黄芩苷的质量浓度为4.05 ～5.05 g/L,符合药典规定.     

Application of high-speed counter-current chromatography to the preparative separation and purification of baicalin from the Chinese medicinal plant Scutellaria baicalensis

Baicalin was separated and purified for the first time from the traditional Chinese medicinal plant Scutellaria baicalensis Georgi by high-speed counter-current chromatography. Crude baicalin was obtained by extraction with methanol-water (70:30, v/v) from S. baicalensis Georgi. The separation was performed in two steps with a two-phase solvent system composed of n-butanol-water (1:1, v/v), in which the lower phase was used as the mobile phase at a flow-rate of 1.0 ml min(-1) in the head-to-tail elution mode. A total of 37.0 mg of baicalin at 96.5% purity was yielded from 200 mg of the crude baicalin (containing 21.6% baicalin) with 86.0% recovery as determined by HPLC analysis.     

Separation and purification of baicalin and wogonoside from the Chinese medicinal plant Scutellaria baicalensis Georgi by high-speed counter-current chromatography

A preparative high-speed counter-current chromatography (HSCCC) method for isolation and purification of baicalin and wogonoside from the Chinese medicinal plant Scutellaria baicalensis Georgi (Huang-qin in Chinese) was successfully established by using ethyl acetate-methanol-1% acetic acid water (5:0.5:5, v/v) as the two-phase solvent system. The upper phase of ethyl acetate-methanol-1% acetic acid water (5:0.5:5, v/v) was used as the stationary phase of HSCCC. Baicalin (58.1 mg) and wogonoside (17.0mg) with the purity of 99.2 and 99.0%, respectively, were separated successfully in one-step separation from 120 mg of crude sample from S. baicalensi, Georgi. The structures of baicalin and wogonoside were identified by 1H NMR and 13C NMR.     

不同产地黄芩中黄芩甙及元素的含量比较

用高效液相色谱法和原子吸收光谱法分别对１０个不同产地正品黄芩中黄芩甙及元素的含量进行了分析比较。     

6,7-二乙酰氧基黄芩素的一步合成、选择性水解及甲醚化

以中药黄芩中的主要活性成分黄芩苷为原料,在醋酸钾、吡啶催化回流条件下,用醋酐为乙酰化试剂,以67.6%的收率一步实现了6,7-二乙酰氧基黄芩素的合成,6,7-二乙酰氧基黄芩素经K2CO3/丙酮-水条件下的水解反应或Me2SO4/K2CO3/丙酮中的甲醚化反应以良好收率及高选择性得到6-乙酰氧基黄芩素或7-甲氧基-6-乙酰氧基黄芩素.     

Simple preparation of baicalin from Scutellariae Radix

A simple, rapid and reproducible method was developed to isolate high-purity baicalin from Scutellariae Radix, the dried roots of Scutellaria baicalensis Georgi. The method involves partition/recrystallization steps without repeated column chromatography or special instruments. Isolated baicalin was characterized by comparisons of TLC, HPLC, IR, MS, and NMR data with an authentic sample. Moreover, beta-glucuronidase hydrolysis of baicalin sequentially yielded glucuronic acid and baicalein as confirmed by co-TLC with authentic samples. The purity of baicalin was more than 97% with yield ca. 8.7% (w/w). The method presented here appears suitable for commercial application.     

Determination of baicalin, chlorogenic acid and forsythin in Chinese medicinal preparation by capillary electrophoresis

Summary The determination of baicalin, chlorogenic acid and forsythin in a traditional Chinese medicinal preparation, Shuanghuanglian oral liquid, has been investigated by micellar electrokinetic capillary electrophoresis using borate buffer, SDS and acetonitrile as background electrolyte, 15 kV applied voltage and UV detection, the three active compounds were completely separated within 15 min. The effect of buffer pH, concentration of borate and SDS are discussed. Regression equations reveal linear relationships between the peak-area of each component and content. In addition, the levels of three active compounds in traditional Chinese medicinal preparation, Shuanghuanglian oral liquid, were easily determined with recoveries of 95.20–105.73%.     

Isolation and purification of baicalein, wogonin and oroxylin A from the medicinal plant Scutellaria baicalensis by high-speed counter-current chromatography

The medicinal plant Scutellaria baicalensis Georgi has been used widely in traditional Chinese medicine for anti-inflammation, anticancer, antiviral and antibacterial infections, reducing the total cholesterol level and decreasing blood pressures. A high-speed counter-current chromatography (HSCCC) method was developed for the preparative separation and purification of three bioactive flavonoids, namely, baicalein, wogonin and oroxylin A, from S. baicalensis Georgi. Preparative HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-n-butanol-water (1:1:8:10, v/v/v/v) was successfully performed by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml min(-1) after 4 h. The components purified and collected were analyzed by high-performance liquid chromatography. The method yielded 144.8 mg of baicalein at 95.7% purity, 50.2 mg of wogonin at 98.5% purity, and 12.4 mg of oroxylin A at 93.2% purity from 500 mg of the crude extract in a one-step separation. The recoveries of baicalein, wogonin and oroxylin A were 92.7%, 91.6% and 92.5%, respectively.     

Solid-state NMR studies and DFT calculations of flavonoids: baicalein, baicalin and wogonoside

Three flavonoids of pharmaceutical importance-baicalein, baicalin, and wogonoside-were isolated from a Chinese medicinal plant Scutellaria baicalensis Georgi and studied by 13C NMR in solution and solid state. Two-dimensional (2D) NMR spectroscopy in the liquid phase and dipolar dephasing (DD) experiments in magic-angle spinning (MAS) spectra enabled the assignment of 13C resonances. The cross-polarization (CP) time constants T(CH) and relaxation times T(H) (1rho) were obtained from the variable-contact time experiments. The principal elements of the 13C chemical shift tensor were determined in the spectra recorded under slow sample spinning (2 kHz) using phase-adjusted spinning sideband (PASS)-2D NMR technique, and were verified by density functional theory gauge-independent atomic orbital (DFT GIAO) calculations of shielding constants. Analysis of the 13C delta(ii) and comparison with shielding parameters calculated for different conformers of compounds 1-3 enabled the selection of the most reliable geometry in the solid phase. In all three compounds, an intramolecular hydrogen bond C5--OH...=C4 is formed; the existence of baicalein and baicalin with 'anticlockwise' orientation of OH groups is more probable.     

HPLC Determination of Flavonoids in Hairy-Root Cultures of <Emphasis Type="Italic">Scutellaria baicalensis</Emphasis> Georgi

A simple and sensitive liquid chromatographic method has been established for determination of the main flavonoid components of Scutellaria baicalensis Georgi (Lamiaceae) roots and hairy-root cultures. Wogon, the dried root of the plant, is used in traditional Chinese medicine for treatment of bronchitis, hepatitis, tumors, and inflammatory diseases. Lyophilized hairy roots were extracted with methanol. The crude extracts were purified by SPE on Supelco LC-8 cartridges. HPLC separations were performed on a Eurospher 100-C₈ reversed-phase column. The mobile phase was a gradient prepared from mixtures of acetonitrile and 0.1% trifluoroacetic acid. Peaks were identified by addition of standards and/or by diode-array detection. Baicalein 7-O-glucuronide (baicalin), wogonin 7-O-glucuronide (wogonoside), baicalein, wogonin, and acteoside were determined by the external standard method at 280 nm. We found that the aglycon (baicalein and wogonin) content of the transformed roots was consistently higher than that of the intact root from Siberia.