Development a Spectrophotometric of Fe(Ⅲ), Al(Ⅲ) and Cu(Ⅱ) Using Eriochrome Cyanine R Ligand and Assessment of the Obtained Data by Partial Least-Squares and Artificial Neural Network Method-Application to Natural Waters

Simultaneous determination of heavy metal cations and accurate quantitative prediction of them are of great interest in analytical chemistry.This work has focused on a comprehensive comparison of partial least squares(PLS-1)and artificial neural networks(ANN)as two types of chemometric methods.For this purpose,aluminum,iron and copper were studied as three analytes whose UV-Vis absorption spectra highly overlap each other.Accordance with determined parameters(ligand concentration,pH,waiting times,the relationship between absorbance and concentration of metal ion effect and foreign ions)are provided and the optimum conditions.After establishing the optimum conditions for Fe^(3+),Al^(3+) and Cu^(2+) containing mixtures spectrophotometric determinations and the data calibration method of least squares(PLS-1)regression,and artificial neural network(ANN)methods were used.Chemometric methods are applied in a fast,simple,and the results are applicable.

Extraction and Determination of Three Chlorophenols by Hollow Fiber Liquid Phase Microextraction - Spectrophotometric Analysis, and Evaluation Procedures Using Mean Centering of Ratio Spectra Method

A method termed hollow fiber liquid phase microextraction (HF-LPME) was utilized to extract three chlo- rophenols, 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6- trichlorophenol (2,4,6-TCP), separately from water. The extracted chlorophenols were then separated, identified, and quantified by UV-Vis spectrophotometry with photodiode array detection (UV-Vis/DAD). In the study, experimental con-ditions such as organic phase identity, acceptor phase volume, sample agitation, extraction time, acceptor phase NaOH concentration, donor phase HCl concentration, salt addition, and UV absorption wavelength were optimized. The statistical parameters of the proposed method were investigated under the selected con-ditions. The analytical characteristics of the method such as detection limit, accuracy, precision, relative standard deviation (R.S.D.) and relative standard error (R.S.E.) was calculated. The results showed that the proposed method is simple, rapid, accurate and precise for the analysis of ternary mixtures.

Determination of Azacitidine by Spectrophotometric Method

Simple, selective and sensitive spectrophotometric method has been developed for the determination of Azacitidine in pharmaceutical formulations and blood with MBTH (3-methyl-2-benzothiazolone hydrazone hydrochloride) reagent, at PH-4.0 which is extractable at 620 nm. Beer’s law is obeying in the concentration ranges 10 - 35 μg·ml-1 for formulations and 4 - 24 μg·ml-1 for blood sample. %R.S.D was found to be 0.0240%, 0.0610 and Recovery 99.82% 99.24% respectively. The method was completely validated and proven to be rugged. The interferences of the other ingredients and excipients were not observed. The repeatability and the performance of the proven method were conventional by point and interior proposition and through recovery studies.

Developed New Procedure for Low Concentrations of Hydrazine Determination by Spectrophotometry: Hydrazine-Potassium Permanganate System

An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. In this proposed the spectrophotometric method is based on its reduction properties of hydrazine with a known concentration of potassium permanganate to reduce the colour. The absorbance of unreduced permanganate is measured the colour difference at different wavelengths 546 and 526 nm which show an absorption spectrum with hydrazine. Hydrazine can be determined in the range of 100 - 700 μg/ml with correlation coefficient of 0.999 and relative standard deviation 1%. The method is successfully applied for the determination of hydrazine in water streams in nuclear reactors/purex process/boiler water and polluted water samples.

分光光度法测定食品中硼砂

目的 :建立姜黄素分光光度法测定食品中硼砂含量的方法。方法 :食品在碱性条件下灰化 ,在酸性条件下姜黄素分光光度法测定硼砂含量。结果 :方法的线性好 (r=0 .9999) ,样品测定的相对标准差 rsd<5 % ,加标回收率为 90 .0 %～ 10 4 .5 % ,检出限为 0 .0 6 mg/kg。结论 :该方法灵敏、准确、精密、易于操作 。

光度法研究姜黄素金属络合物与鲑鱼精DNA的相互作用

采用紫外可见分光光度法研究了姜黄素(CUR)的光谱特性及其金属络合物与鲑鱼精DNA的相互作用。结果表明,在pH值为6.5的Tris-HCl缓冲溶液中,姜黄素的特征吸收峰在430 nm处,Fe3+-CUR形成了1∶3的金属络合物,其结合常数KD=4.326×104L/mol,确定了Fe3+-CUR与鲑鱼精DNA之间有嵌插作用存在,其结合常数KD=136.24 L/g。

光度法测定压裂返排液中硼酸的含量

压裂施工完成后会产生大量的压裂返排液,将其简单处理后再次用于压裂液的配制,不仅可以节约处理废水的成本,还可以避免污染环境、浪费水资源。准确测定其中硼酸的含量,对消除返排液中硼酸的影响、成功重复利用返排液具有重要意义。实验探索了萃取-紫外分光光度法并筛选了关键的实验条件,其次还探索了姜黄素可见分光光度法。实验结果表明:两种方法都能够准确测定返排液中硼酸的含量,其中姜黄素可见分光光度法每次需配制新鲜的姜黄素-草酸溶液,需对水样除去钙镁且显色后还要离心处理;相比来说萃取-紫外分光光度法操作方法更简单,共存离子对测定结果的干扰更小。

紫外分光光度法测定姜黄素固体脂质纳米粒的包封率

建立姜黄素固体脂质纳米粒的包封率测定方法。采用紫外分光光度法测定姜黄素固体脂质纳米粒中姜黄素的含量,由此计算包封率。透射电镜下姜黄素固体脂质纳米粒成圆形或椭圆形,平均粒径为(130.7±2.4)nm。姜黄素在432 nm处有最大吸收波长,浓度在1.05vg/mL至7.35μg/mL范围时与吸光度呈良好的线性关系,回归方程为:A=0.1320C+0.0310,r=0.9993(n=7);平均回收率为99.39%,RSD为0.49%;测得姜黄素固体脂质纳米粒的包封率为90.90%,RSD为0.82%。本方法操作简单易行,准确度和精密度均符合要求,可用于姜黄素固体脂质纳米粒包封率的测定。

紫外-可见分光光度法定量测定姜黄素及其载体药物方法的优化

目的利用紫外-可见分光光度法建立一种简便快速的姜黄素及载体中药物含量的测定方法。方法采用碱液法测定载体药物中包载的姜黄素的含量,将姜黄素载体药物溶于10 g/L氢氧化钠溶液中,分离出载体后在最大吸收波长470 nm处用紫外-可见分光光度计对姜黄素含量进行测定,根据标准曲线计算出载药量。结果姜黄素在8.0~15.0 mg/L浓度(x)下与吸光度(y)有很好的线性关系,得到回归方程为y=0.139x+0.009,r^2=0.999(n=7),1 h内误差<0.4 mg/L。结论该法方便快捷,廉价环保,可用于姜黄素及载体包载量的定量研究。

姜黄素光度法测定硼量国际标准的共同试验

用国际标准草案[1 ] (DIS)与现行国家标准 (GB)方法相对照 ,对硼的测定条件进行试验、验证。采用盐酸 -硝酸溶解试样 ,在 2 90℃以硫酸 -磷酸分解硼化物 ,在乙酸缓冲溶液中 ,硼与姜黄素生成有色络合物 ,ε543=1 2× 10 5,用本方法测定的硼量与全硼标准值基本相等 ,方法的准确度及重复性较好 ,对DIS与GB的差别进行了探讨 ,提出了改进意见。

光度法研究姜黄素与铁(Ⅲ)的络合反应

目的研究姜黄素与铁(Ⅲ)的络合反应,并建立铁的测定方法。方法采用分光光度法。结果在10^(-5)～10^(-3)mol/L范围内,姜黄素有不同的吸收光谱;其与铁络合物的吸收波长由430nm红移至496 nm,呈增色反应。在pH 5.60,浓度为6.51×10^(-4)moL/L姜黄素液中,络合物为酒红色,λ_(max)=496 nm,ε=3.86×10~6L/mol·cm,铁(Ⅲ)的线性范围为0.20～2.00μg/mL。结论在较高浓度下自动聚合的姜黄素与铁(Ⅲ)反应更灵敏。在此基础上,建立的姜黄素测定铁的分光光度法操作简单,选择性较好,灵敏度高,用于自来水中铁(Ⅲ)的测定,结果满意。

分光光度法测定中毒样品中硼砂

目的：建立姜黄素分光光度法测定中毒样品中的硼砂。方法：中毒样品在碱性条件下灰化,在酸性条件下姜黄素分光光度法测定硼砂含量。结果：方法的线性好（r=0.9998）,样品测定的相对标准差RSD〈5%,加标回收率91.3%～103.8%,检出限为0.06 mg/kg。结论：该方法灵敏、准确、易于操作,适用于中毒样品中硼砂的测定。

硅铁合金中痕量硼的分光光度测定

建立了蒸馏分离 -姜黄素光度法测定硅铁合金中痕量硼的方法。对在氢氟酸介质中溶样时痕量硼的挥发损失及其络合保护问题进行了试验 ,结果表明 ,通过加入适量甘露醇络合保护 ,可有效地防止痕量硼在样品溶解及其溶液蒸发过程中的挥发损失 ,并成功地用于实际样品分析 ,取得了令人满意的结果。同时 ,对所拟溶样条件下所得硼的分析结果是否为全硼问题进行了进一步探讨 ,结果证实 ,所拟溶样条件下硼的测定结果为全硼。

以吐温-80为增溶剂催化光度法测定痕量钒(Ⅴ)

本文报道了在硫酸性介质中 ,以吐温 - 80为增溶剂 ,溴酸钾氧化姜黄催化光度法测定痕量钒 ( )的新体系。方法的检出限为 2 .6× 10 -3mg· L-1;相对标准偏差为 2 .7% (n=9) ,线性范围为 0 .0 12— 0 .0 4 0mg· L-1。可用于测定水样中痕量钒 ( ) 。

双等色点光度法测定姜黄素-铁(Ⅱ)的稳定常数及试验方法改进

采用双等色点光度法测定姜黄素-铁(Ⅱ)络合物的稳定常数并对试验方法进行了改进。采用两种紫外-可见分光光度法设计试验方案,考察了姜黄素的光谱特性,获得姜黄素与铁(Ⅱ)的络合物吸收光谱中两个等色点,姜黄素-铁(Ⅱ)络合物的稳定常数为1.48×1011(pH 6.50),改进后试验方法的稳定常数为1.49×1011。

阻抑-褪色光度法测定痕量硅

基于NH3 NH4 Cl缓冲溶液介质中 ,Si 对H2 O2 氧化十六烷基三甲基溴化铵 姜黄素离子缔合物的褪色反应的抑制作用 ,提出了测定痕量硅新的高灵敏的褪色光度法。该方法的表观摩尔吸光系数ε50 0=5 .70× 10 5L·mol-1·cm-1;线性范围为 0 .4～ 3.6 μg/L ;线性回归方程ΔA =2 .2 3× 10 -4 + 0 .0 2 0 17CSi (μg/L) ;相关系数r =0 .9999;测定下限为 2 0× 10 -8g/L。本法用于人发样和水样中痕量硅的测定 ,结果满意。

β-环糊精富集固相反射散射分光光度法测定铍

研究了用自制的β-环糊精 (β- CD)交联聚合物树脂对姜黄素铍络合物进行包结吸附 ,用固相反射散射分光光度法测定铍。 β- CD树脂包结姜黄素铍络合物后提高体系灵敏度 ,Be O的浓度在 0～ 0 .2μg/m L有良好的线性关系 ,结果与标准值相符。检出限为 7.5 μg/L,测定 1 μg Be O1 1次 ,相对标准偏差为 3.8%

Process Optimization and Content Determination of Total Flavonoids of Zhuang Medicine Clerodendrum japonicum(Thumb.)Sweet

[Objectives]To optimize the extraction process of total flavonoids of Zhuang medicine Clerodendrum japonicum(Thumb.)Sweet and establish a method for its extraction and content determination.[Methods]The total flavonoids of C.japonicum were extracted by reflux extraction method.Through a single factor experiment,the effects of extraction method,extraction solvent concentration,extraction volume and extraction time on the total flavonoids content of medicinal materials were investigated to select the optimal extraction process of the total flavonoids of C.japonicum.[Results]The optimal extraction process of the total flavonoids of C.japonicum was 75%ethanol,1∶20 solid-to-liquid ratio,and 50 min reflux extraction time.[Conclusions]This method can effectively determine the content of total flavonoids in C.japonicum and provide a certain scientific basis for the study of the quality standard of this Zhuang medicine.This method has high reproducibility.It is stable and feasible in extraction of total flavonoids from Zhuang medicine C.japonicum.

紫外分光光度法测定姜黄素囊泡中姜黄素的含量

目的:建立紫外分光光度法测定姜黄素囊泡中姜黄素的含量的方法。方法:采用紫外可见分光光度法测定姜黄素囊泡中姜黄素的量。结果:姜黄素在426 nm处有最大吸收,浓度在2.10～6.30 mg·mL-1时与吸光度呈良好的线性关系,回归方程为:A=0.1302C+0.0424,r=0.9999(n=3);平均回收率为98.47%,RSD为0.93%(n=9)。本方法操作简便易行,具有良好的重现性和精密度。

姜黄素-分光光度法测定药物中的Fe^(2+)

建立姜黄素-分光光度法测定药物中Fe2+的方法。采用简单的紫外-可见分光光度法,以姜黄素为显色剂,Tris-HCl(pH=6.50)为缓冲溶液,在432nm处测定复方硫酸亚铁叶酸片中的ρ(Fe2+)。ρ(Fe2+)在0.40~8.00μg/mL线性关系良好,回归方程为A=0.047 4x+0.323 7(r=0.999 5),平均回收率为100.2%,RSD=0.6%。该方法快速准确,灵敏度高,为药物中Fe2+的测定提供可靠的分析手段。