群多普利原料药含量测定检查方法研究

目的:建立群多普利(Trandolapril)原料药含量测定方法。方法:含量检查方法采用苯基柱Ph-3(Inertsil,250mm*4.6mm,5u),选用乙腈-水(0.02mol/L磷酸二氢钾,磷酸调pH至2.7)(48:52)作流动相,检测波长220nm。含量测定采用酸碱滴定法和高效液相色谱法。结果:在建立的色谱条件下,各种降解产物均能与群多普利主峰分开,方法专属性强,滴定法与HPLC法含量测定结果无显著性差异。结论:建立得HPLC方法可用来对群多普利原料药进行含量测定,由于本品属于原料药,最终含量测定方法采用滴定法。     

乌头须根总生物碱提取工艺的考察

目的:考察乌头须根中总生物碱的最佳提取工艺条件。方法:酸碱滴定法测定乌头须根中总生物碱含量,以总生物碱提取率为指标,采用L9(3)~4正交实验法筛选乌头须根总生物碱的最佳提取工艺。结果:乌头须根总生物碱含量为1.094%,影响提取的主次因素为:乙醇浓度>提取次数>提取时间>乙醇用量;优选得到的最佳提取工艺为A_3B_1C_3D_3,即以8倍量80%的乙醇提取3次,每次1.5小时。结论:乌头须根总生物碱含量较高,提取工艺条件稳定、经济、可行。     

营养型复制酒中还原糖对总酯测定的影响

分别运用气相色谱法和电位滴定法对营养型复制酒总酯含量进行测定,结果表明：气相色谱测试复制酒配制前后酒样中总酯含量保持不变;电位滴定法测定的营养酒总酯含量受复制添加的还原糖影响,测试的酒样总酯含量“增加“,且增加量与复制酒中还原糖浓度呈线性关系。当复制酒中还原糖浓度提高1.0g/L,则测定的总酯含量“增加“0.72g/L。用电位滴法测定的结果减去相应还原糖对应的“总酯“增加值,即为复制酒中的总酯含量。     

瘤普霖原料药含量测定方法的研究

本文对瘤普霖原料药分别采用电位滴定法、氧瓶燃烧法、凯氏定氮法、pH指示剂吸收度比值法和交流示波极谱滴定法进行了含量测定,并对五种方法进行了比较。实验结果表明,pH指示剂吸收度比值法和交流示波极谱滴定法简单、快速、灵敏度高。     

甘油转化生产1,3-丙二醇发酵液中甘油含量的测定

对文献介绍滴定法测定甘油的方法进行了改进,使之能够用于1,3－丙二醇发酵液中甘油含量测定。实验表明,化学滴定法测定结果具有较好的准确性和重复性,与酶法和变色酸比色法相比,测定结果接近,化学滴定法测定发酵液中甘油含量是一个较为经济简便的方法。     

高效液相色谱法测定丙谷胺片的含量

丙谷胺是一种胃泌素拮抗剂,其含量测定方法《中国药典》2000年版二部及《中国药典》2005年版二部采用的是滴定法,本文试用高效液相色谱法（HPLC法）测定其含量,此法操作简便,重现性好,结果准确可靠。     

不同品种花椒生物碱含量测定及光谱学特性分析

建立了一种酸碱滴定法有效的生物碱定量测定方法,并比较测定了花椒的两个品种花椒和青花椒中生物碱的含量。对生物碱提取液在紫外扫描图谱的基础上分析了花椒和青花椒生物碱的差异,有望将此紫外图谱应用到不同品种花椒生物碱的指纹图谱上。     

低糖型糖果中总糖含量的测定

目的:确定低糖型糖果总糖含量的测定方法。方法:在各种实验文献的基础上,探索了直接滴定法检测总糖的检测方法,并根据实际情况,对方法进行改良。结果:该方法使总糖测定的实验条件得到改进和完善,降低了试验误差,产生了良好效果。结论:该方法测定总糖含量具有精密度高和重现性好的优点,可用于低糖型糖果的质量控制。     

威灵仙药材中掺入MgSO4的检出和含量测定

目的:对威灵仙药材中非法掺入的MgSO4进行检出和含量测定.方法:采用X射线元素分析法和EDTA络合滴定法.结果:确立了对威灵仙中非法掺入的MgSO4的检出和含量测定方法.本实验首先将分离得到的结晶进行结构鉴定,确定为硫酸镁,再在高温下使有机物完全灰化后,利用EDTA络合滴定法,准确测定其中镁的含量,有效避免了其他组分的干扰.结论:该法具有操作简便、精密度高、重现性好等优点,对威灵仙的临床用药安全具有重要的现实意义,也能为其它非法掺入镁盐的中药材质量进行有效监控.     

容量滴定法和库伦滴定法测定冻干疫苗水分含量的比较

目的在适宜的温度和湿度条件下,评价容量滴定法和库伦滴定法测定冻干疫苗水分是否具有差异性。方法确定冻干疫苗水分测定的适宜温度和湿度条件,在此条件下,分别从水分含量区间、冻干疫苗类型和进样量三个主要影响方面,对容量滴定法(volumetric titration)和库伦滴定法(coulometric titration)进行比较。结果冻干疫苗水分测定的适宜条件为:温度25℃、湿度45%。冻干疫苗水分的质量分数为1.0%～2.0%时,容量滴定法和库伦滴定法的检测结果差异有统计学意义(P0.05);水分的质量分数在2.0%～3.0%时,两种滴定法的检测结果差异无统计学意义(P0.05)。对于不同类型冻干疫苗和不同进样量的冻干疫苗,两种滴定法检测结果差异均无统计学意义(P均0.05)。结论在适宜的温度和湿度条件下,库伦滴定法更适用于低水分含量冻干疫苗的水分测定;其他情况下两种滴定法无明显差异。     

Electron microscope detection of biogenic amines in the medulla of the adrenal gland of the normoglycemic spiny mouse (Acomys cahirinus)

By means of a modification of the Reinecke salt method already described, characteristical amine containing granules have been demonstrated in the parenchymal cells of the adrenal medulla in normoglycemic spiny mice. By this method two types of granules have been discerned according to their different contrasts. The advantages of the modification method are discussed.     

Structural and functional changes in complement protein C4 under UV irradiation

The influence of ultraviolet (UV) light on the structural and functional states of the complement factor C4 was investigated using hemolytic and acid-base titration, PAG electrophoresis, and IR and UV spectrophotometry. UV doses of 75.5 and 755 J/m² initiated C4 activation through changes in the globule structure (increased number of aromatic amino acids and ionogenic groups at the surface). The maximal dose of 2265 J/m² has a destructive effect and decreases its C4 activity in the cascade of hemolytic reactions of the complement system.     

Determination of protoberberine alkaloids in medicinal plants based on acidic potassium permanganate chemiluminescence system

A simple method was established to determine protoberberine alkaloids in Cortex Phellodendri and Rhizoma Coptidis based on an acidic potassium permanganate chemiluminescence (CL) system. The optimum conditions for the CL reaction between protoberberine alkaloids and potassium permanganate were studied in detail. Under the optimum conditions, the linear response ranges for berberine, palmatine and jatrorrhizine were 0.038–7.27, 0.031–18.1 and 0.012–3.61 μg/mL with detection limits of 0.005, 0.004 and 0.0007 μg/mL, respectively. This method was successfully applied to determine the content of protoberberine alkaloids (calculated using berberine as an index) in Cortex Phellodendri and Rhizoma Coptidis. In addition, a possible mechanism of this CL reaction was proposed on the basis of the investigation of CL, UV and fluorescent spectra of protoberberine alkaloids in acidic solution containing potassium permanganate. Copyright © 2009 John Wiley & Sons, Ltd.     

Determination of saponins and alkaloids in Caulophyllum thalictroides (blue cohosh) by high-performance liquid chromatography and evaporative light scattering detection

The roots of Caulophyllum thalictroides, traditionally used for the treatment of menstrual difficulties and as an aid in childbirth, contain saponins, which are considered to be responsible for the uterine stimulant effects, together with teratogenic alkaloids. An HPLC method has been developed which permits the determination of the triterpene saponins in the plant and also the separation of four alkaloids. The best results were obtained with a C-12 stationary phase using ammonium acetate buffer (pH 8.0) and acetonitrile as mobile phase. Owing to their low UV absorbance, the saponins were detected by evaporative light scattering, whereas the alkaloids were monitored by UV at 310 nm. The identities of the compounds were confirmed in an LC-MS experiment. Different plant samples and commercial products have been analysed using the described method, and remarkable qualitative and quantitative variations were revealed. Comparing the daily uptake of total saponins, a difference of greater than 100-fold was observed within the various products; the alkaloid content on the other hand was more uniform.     

DNA-binding affinities and sequence specificities of protoberberine alkaloids and their demethylated derivatives: a comparative study

Berberrubine (1a), jatrorubine (2a), and palmatrubine (3a) have been chemically prepared by partial demethylation of berberine (1), jatrorrhizine (2), and palmatine (3), respectively. Their interactions with calf thymus (CT) DNA, poly(dA-dT)poly(dA-dT), poly(dG-dC)poly(dG-dC), and eight AT-rich 12-mer double-stranded DNAs have been investigated by means of competitive ethidium bromide (EB) displacement experiments. The results showed that DNA-binding affinities of these protoberberine alkaloids have been significantly improved by partial demethylation, and that all of these alkaloids have the preferable binding affinities with AT-rich DNA. Especially, the sequence specificities of DNA-binding of demethylated derivatives 1a, 2a, and 3a had changed to a certain extent when compared with the parent alkaloids 1, 2, and 3, respectively. The binding mode of these alkaloids was further confirmed by UV spectroscopic titration experiments. All the compounds bind to double-stranded DNA most probably via an intercalating mode.     

Analysis of goldenseal, Hydrastis canadensis L., and related alkaloids in urine using HPLC with UV detection

A screening method was developed to extract and detect berberine and hydrastine alkaloids from goldenseal root powder and urine samples using HPLC with UV detection. The isocratic method was developed to detect alkaloids in 5 mL of urine prior to drug screening. Urine samples were spiked with the alkaloids at varying concentrations and extracted twice with 3:1 chloroform:2-propanol (CHCl(3):2-propanol). The extracts were combined, concentrated using nitrogen gas and the residue was then reconstituted with a mobile phase of acetonitrile:buffer (32:68). A 17 min isocratic run time was performed with a flow rate of 2.0 mL/min, and UV detection at 230 nm using a C(18) (250 mm × 4.6 mm) column at room temperature. The method showed good linearity for berberine (r(2)=0.9990) and hydrastine (r(2)=0.9983) over a range of 11.80 ng/mL to 17.64 μg/mL. The LOD for berberine in urine was 12.74 ng/mL and the LOD for hydrastine in urine was 54.48 ng/mL. Urine samples were spiked with goldenseal root powder and liquid extract as part of a blinded study to determine whether berberine and hydrastine alkaloids could also be extracted in vitro from goldenseal and show a presence in urine samples. Out of the 37 blinded urine samples extracted the two spiked samples were correctly identified based on the presence or absence of berberine and hydrastine. The results demonstrated that this method will enable laboratories to test for the herbal supplement in submitted urine samples prior to drug testing, avoiding false negative results.     

RNA binding small molecules: studies on t-RNA binding by cytotoxic plant alkaloids berberine, palmatine and the comparison to ethidium

The interaction of two natural protoberberine plant alkaloids berberine and palmatine with t-RNA(phe) was studied using various biophysical techniques and the data was compared with the binding of the classical DNA intercalator, ethidium. The results of optical thermal melting, differential scanning calorimetry and circular dichroism characterized the native cloverleaf structure of t-RNA under the conditions of the study. The strong binding of the alkaloids and ethidium to t-RNA was revealed from the absorption and fluorescence studies. The salt dependence of the binding constants enabled the dissection of the binding free energy to electrostatic and non-electrostatic contributions. This analysis revealed a surprisingly large favourable component of the non-electrostatic contribution to the binding of these charged alkaloids and ethidium to t-RNA. Isothermal titration calorimetric studies revealed that the binding of both the alkaloids is driven by a moderately favourable enthalpy decrease and a moderately favourable entropy increase while that of ethidium is driven by a large favourable enthalpy decrease. Taken together, the results suggest that the binding of these alkaloid molecules on the t-RNA structure appears to be mostly by partial intercalation while ethidium intercalates to the t-RNA. These results reveal the molecular aspects on the interaction of these alkaloids to t-RNA.     

Separation and measurement of plant alkaloid enantiomers by RP-HPLC analysis of their Fmoc-Alanine analogs

Introduction . Ammodendrine ( 1 ), anabasine ( 2 ) and coniine ( 3 ) can cause congenital malformations in livestock. They appear naturally in both enantiomeric forms, and can cause variable physiological responses. A method to measure the enantiomeric ratio of these natural toxins is needed. Objective . To develop a simple and economical method in order to determine the enantiomeric ratios of piperidine and pyrrolidine alkaloids in small samples of plant material. Methodology . Mixtures of isolated or purified plant alkaloids were converted to their Fmoc‐l ‐Ala‐alkaloid analogues forming diastereomeric mixtures, which were then analysed by high pressure liquid chromatography (HPLC) with mass spectrometry (MS) and ultraviolet (UV) detection to determine enantiomeric ratios. Results . The diastereomeric analogs for ammodendrine, anabasine and nornicotine could be separated and the enantiomeric ratios determined. The Fmoc‐l ‐Ala‐coniine analogue was not resolved under the HPLC conditions studied. The enantiomeric ratios of the selected plant alkaloids were measured and found to differ between both location within a species and location between species. Conclusion . A low‐cost HPLC method to analyse the enantiomeric ratio of plant alkaloids containing primary or secondary amine nitrogens via conversion to their respective diastereomeric analogues has been developed. Published in 2008 by John Wiley & Sons.