示波极谱滴定法测定植物中钾含量的研究

示波极谱滴定法测定植物中的钾未见报道,本文用示波极谱滴定法对植物中钾的测定,做了多方面的研究。实验表明以ＨＡｃ－ＮａＡｃ为底液ｐＨ＝５．０的缓冲溶液中,加入过量的标准四苯研究钠（Ｎａ－ＴＰＢ）溶液,然后用标准ＡｆＮＯ３溶液滴定过量的四苯硼钠,利用四苯硼钠示波极谱曲线（ｄＥ／ｄｔ＝ｆ（Ｅ））上有切口,并和Ａｇ＋能定量反应,使切口消失为终点。测定结果满意。该法直观、简便、快速、灵敏、准确、不用加指示剂。溶液混浊、沉淀及有色,均不干扰测定,适用于植物中钾的测定。     

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。     

混合氨基酸含量测定新方法

介绍用交流示波极谱滴定法测混合氨基酸的含量。在ＫＣｌ底液中,利用ＨＣＨＯ将－ＮＨ２封闭,用ＫＯＨ标准液滴定,ＨＣＨＯ同时做指示剂,以极谱图形的敏锐变化指示终点的到过,测定结果准确。     

测定缬氨酸含量的新方法—交流示波极谱滴定法

用交流示波极谱滴定法测缬氨酸的含量。在KCl底液中用KOH标准溶液滴定,不需加指示剂,而以极谱图形的变化指示终点的到达。     

四苯硼钠容量法测定谷氨酸钾注射液钾含量

目的:研究建立四苯硼钠容量法测定谷氨酸钾注射液中钾离子含量的方法.方法:分别采用四苯硼钠容量法与四苯硼钠重量法测定谷氨酸钾注射液中钾的含量,并比较其测定结果.结果:四苯硼钠容量法平均加样回收率为102.50%(RSD=0.41%,n=9),与四苯硼钠重量法所测得的结果进行t检验,结果无显著性差异.结论:四苯硼钠容量法简便、快速、准确,可替代四苯硼钠重量法快速测定谷氨酸钾注射液中钾的含量.     

复合季铵盐消毒剂含量的测定与滴定误差分析

研究复合季铵盐消毒剂含量的测定与滴定误差分析。探讨了四苯硼钠标准液配制及对滴定分析终点颜色的影响,并与单季铵盐定量分析方法进行了对比。结果表明:四苯硼钠两相滴定法适合于复合季铵盐定量分析,但要注意四苯硼钠标准液配制的正确性及滴定终点颜色的判断。     

抗坏血酸氧化酶活性的脉冲极谱法测定

用微分脉冲极谱法测定了各种植物样品中抗坏血酸氧化酶的活性,并研究了其影响因素。与传统的滴定法相比,结果完全一致。其方法简便快速,重现性好。     

Zn(Ⅱ)——蛋白质络合物的极谱研究与应用

蛋白质的NaOH-盐酸胍溶液在60℃恒温水浴中加热后与Zn(II)反应生成稳定的络合物,在pH9.4的NaOH-NH4Cl缓冲介质中于单扫描示波极谱上产生一灵敏的极谱波,Ep在-0.60V左右(vs,SCE),其一阶导数波高Hp与蛋白质浓度成线性关系.相关系数R达0.998以上,检测限为0.1μg/mL.利用该波可以测定人血清样品中蛋白质的含量,结果与经典的考马斯亮蓝染色法相一致,方法具有简便、灵敏、取样量少等优点.     

Zn(Ⅱ)-蛋白质络合物的极谱研究与应用

蛋白质的NaOH -盐酸胍溶液在 6 0℃恒温水浴中加热后与Zn(II)反应生成稳定的络合物 ,在 pH9.4的NaOH -NH4Cl缓冲介质中于单扫描示波极谱上产生一灵敏的极谱波 ,Ep在 - 0 .6 0V左右 (vs,SCE) ,其一阶导数波高Hp与蛋白质浓度成线性关系。相关系数R达 0 .998以上 ,检测限为 0 .1μg/mL。利用该波可以测定人血清样品中蛋白质的含量 ,结果与经典的考马斯亮蓝染色法相一致 ,方法具有简便、灵敏、取样量少等优点     

两相滴定法测定苦参片中苦参碱的含量

用两相滴定法测定苦参片中苦参碱的含量。用NaCl饱和溶液为水相,含苦参碱的CHCl3为有机相,0．1％邻氯酚红为指示剂,在两相溶液中加入定量的酸标准液,充分振摇后,用标准碱液剩余滴定。加标回收,测定6次,平均回收率为：99．67％;RSD为1．86％(n=6)。     

Calcium and potassium ion binding by tobacco mosaic virus ribonucleic acid

Calcium and potassium ion titration experiments were performed on solutions of tobacco mosaic virus RNA using ion-specific electrodes. The data obtained were analyzed using Scatchard and Klotz plots for the number of binding sites per nucleotide (n), and the apparent stability constant for complex formation, beta Me. The experimental design also allowed for the determination of the number of protons released per metal ion bound, chi. The calcium ion titration in water yielded values of 0.45 for n, 6.03 for log beta Ca and 0.24 for chi. When this titration was repeated in 0.01 M-KCl, the values were found to be 0.11 for n, 5.08 for log beta Ca and zero for chi. An aqueous potassium titration was also performed, with values for n, log beta K and chi of 0.25, 2.96 and less than 0.10, respectively.     

The spectrophotometric determination of nanomole quantities of chloride in plant tissue

The determination of Cl- in plant tissues was investigated by FeSCN2+ spectrophotometry following SCN- displacement from Hg(SCN)2 by Cl-. The calibration curve was nonlinear, but consistent and reproducible. As little as 10 nmol Cl- could be measured. There was no obvious interference in color development by water-soluble components in plant tissues. Values obtained by this method were in close agreement with those obtained potentiometrically and by coulometric titration.     

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。     

十种植物造纸原料中金属离子的含量研究

对造纸工业常用的 1 0种植物原料 ,采用原子发射光谱法、原子吸收分光光度法和微分脉冲吸附溶出伏安法 ( DPS) ,对其中的金属离子含量进行了研究。结果表明 :各种植物所含的金属元素种类和含量不同 ;同一大类的植物其所含的金属元素也不尽相同。     

A modified method for determining protein binding capacity of plant polyphenolics using radiolabelled protein

A modified radiochemical protein binding method for determining the protein binding capacity of plant polyphenolics (tannins) is described. Purified tannin or unfractionated plant extracts were immobilised on filter paper discs and incubated with the 125I-labelled bovine serum albumin. Protein bound to the disc was proportional to the amount of tannin applied to the disc, although at high concentrations of polyphenolics the discs became saturated and the relationship was no longer applicable. The method was validated using purified procyanidin from Sorghum grain and has been applied to crude polyphenolic extracts from maple, white oak, black oak, walnut and tulip poplar leaves. Specific chemical assays for the determination of proanthocyanidins (acid butanol method) and hydrolysable tannins (modified potassium iodate method) were employed to validate the new protein binding method with the complex plant extracts.     

A simple method for the determination of heparin content in heparin--sepharose.

A potentiometric titration method for the determination of heparin content in heparin-Sepharose is suggested. The procedure is simple and rapid.     

A new linear potentiometric titration method for the determination of deacetylation degree of chitosan

The degree of deacetylation (DD) is one of the most important properties of chitosan. Therefore, a simple, rapid and reliable method for the determination of DD of chitosan is essential. In this report, two new potentiometric titration functions are derived for the determination of DD of chitosan. The effects of the precipitation and the errors induced in pH measurement are discussed in detail. To make this method more simple and reliable, two universal pH regions for the accurate plotting of different DD chitosan samples are proposed for the new potentiometric titration functions. The DD values of three chitosan samples obtained with this new method show good agreement with those yielded from elemental analysis and ¹H-NMR.     

Quantitative and localized element analysis in cross-sections of spruce [Picea abies (L.) Karst.] needles with different degrees of damage

Summary Proton-induced X-ray microanalysis (micro-PIXE) permits the simultaneous determination of the content and the distribution of elements with atomic numbers higher than Z = 13 in biological samples. This method was used to investigate element content and localization in cross-sections of 6-month-old spruce needles. It was possible to detect the elements silicon, phosphorus, sulphur, chlorine, potassium, calcium, manganese, iron and zinc in semithin (10 m) sections of the needles. The localization of the cationic elements like potassium, calcium and manganese was determined in the one-dimensional line scan mode and in the two-dimensional raster scan mode. To demonstrate the usefulness of this method for forest decline research, element content and localization were compared in needles from two trees, which differed in their degree of damage. We were able to detect differences in the amount of cations and in their distribution inside the needles.     

大孔树脂吸附—高碘酸钾法测定御苁蓉口服液中甘露醇的含量

建立御苁蓉口服液中甘露醇含量测定方法,采用大孔树脂吸附－高碘酸钾氧化法。大孔树脂能有效吸附色素和糖甙类成份,而甘露醇几乎不能被吸附（被泄漏）测定结果平均回收率为101．9％。本法操作简单,测定值可靠。