Study on the inclusion interactions of berberine hydrochloride and cucurbit[7] by spectrofluorimetry

The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.

Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application

The inclusion interaction between three types of methylated-β-cyclodextrins （Me-β-CDs） and albendazole （ABZ） was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1： 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand＇s method （double reciprocal plots）. It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine.

Prediction of Concentration of Animal Fat in Mixture with Vegetable Oil by Multivariate Calibration Associated with Spectrofluorimetry

Total spectrofluorimetry associated with Principal Component Analysis (PCA) was used to discriminate samples of vegetable oil and animal fat. In addition, a multivariate calibration model was developed that combines spectroflurimetry with Partial Least Squares (PLS) for prediction of concentration of animal fat in mixture with vegetable oil. The multivariate calibration model had an R2 value of 0.98098, which indicates the accuracy of the model. This method has potential application in the control of quality of raw material for production of biodiesel. The control of the concentration of animal fat is important because animal fat is more susceptible to oxidation than vegetable oil. Furthermore, high concentrations of animal fats may increase electricity costs for biodiesel production due to the high melting points of saturated fats that solidify at room temperature and cause the fouling and clogging of pipes.

O-(β-hydroxyethyl)rutosides determination by micellar flow injection(FI)-spectrofluorimetry

A simple,eco-friendly.sensitive and economic flow injection spectrofluorimetric method was developed for the determination of O-（β-hydroxyethyl）rutosidcs.The procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-（β-hydroxyethyl）rutosides fluorescence enhancement,increasing considerably the sensitivity of detection.All the variables affecting the fluorescence intensity were studied and optimized.The flow rate was 5 mL/min with detection at 450 nm（after excitation at 346 nm）.A linear correlation between drug amount and peak area was established for 0-（β-hydroxyethyl）rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL（s/n = 3）.Validation processes were performed by recovering studies with satisfactory results.The new methodology can be employed for the routine analysis of 0-（P-hydroxyethyl）rutosides in bulks as well as in commercial formulations.

REVERSE VARIABLE-ANGLE SYNCHRONOUS SPECTROFLUORIMETRY FOR RAPID SIMULTANEOUS DETERMINATION OF CHLOROPHYLL A AND CHLOROPHYLL B

Rapid simultaneous determination of chlorophyll a and chlorophyll b by reverse variable-angle synchronous spectrofluorimetry has been studied on a laboratory-constructed microcomputer-controlled versatile spectrofluorimeter.A method in estimation of scan parameters for the determination of two-component system by variable-angle synchronous spectrofluorimetry has been suggested

美沙拉嗪与β-环糊精的主客体相互作用及其分析应用

采用紫外分光光度法、荧光分光光度法以及核磁共振光谱法研究了美沙拉嗪(MSZ)与β-环糊精(β-CD)的主客体相互作用,同时测试了主客体包合物的热力学参数(ΔG、ΔH、ΔS)。光谱数据表明MSZ-β-CD包合物的形成,包合比为1∶1,包合常数K=1.362×10^(2) L·mol^(-1)。基于MSZ-β-CD包合物荧光强度的显著增大,建立了一个简单、准确、快速、高灵敏度测定水溶液中MSZ的荧光分析新方法。MSZ的浓度与MSZ-β-CD包合物的荧光强度变化值ΔF具有良好的线性关系,相关系数为0.998,线性范围为0.1~0.7 mg·L^(-1),检测限为8μg·L^(-1),该方法可应用于药品中美沙拉嗪的含量测定。

荧光分光光度法测定盐酸氯丙嗪

研究了盐酸氯丙嗪的荧光分光光度测定法 ,在优化的实验条件下 ,该法测定盐酸氯丙嗪的线性范围为 0～2 0× 10 -6g/mL ,检出限为 1× 10 -8g/mL ;对浓度为 5 0× 10 -7g/mL的盐酸氯丙嗪进行 11次平行测定 ,得到相对标准偏差为 2 5 %.将本法用于盐酸氯丙嗪片剂的分析并与药典规定的标准方法对照 ,结果令人满意 .

催化荧光动力学法测定织物中痕量甲醛

在硫酸介质中 ,甲醛可以催化溴酸钾氧化罗丹明 6G的反应 ,使其荧光猝灭 ,据此建立了催化荧光动力学分析法测定痕量甲醛的新方法。方法的线性范围 2 0～ 160 μg/L ,检出限 5 .8μg/L。该法快速简便 ,常见易共存有机物干扰小 ,用于树脂整理特殊织物中痕量甲醛的测定 ,回收率在 96.0 %～ 10 6.0 %之间 。

荧光分析法测定杜仲叶总黄酮含量的研究

根据黄酮类化合物能与 Al3 +形成稳定的荧光络合物 ,建立一种测定杜仲叶总黄酮的新方法。用 6 0 %乙醇加热回流提取杜仲叶有效成分 ,以芦丁为标样 ,选择激发波长 λex=4 36 nm,发射波长 λem=4 83nm,采用荧光分光光度法测定杜仲叶中总黄酮含量 ,并进行加标回收实验 ,验证方法的准确性。方法检出限为1.2 7× 10 -9mol·L-1,线性范围在 1.6 4× 10 -8— 3.6 3× 10 -5mol·L-1之间 ,线性回归方程 :y=17.92 3x+1.398,相关系数 r=0 .9989,平均回收率 99.8%— 10 4 .2 %。相对标准差 (RSD) 0 .84 % ,本法操作简便、快速、准确 ,具有良好的分析应用前景。

生姜对超氧阴离子及羟自由基的清除作用

生姜对次黄嘌呤-黄嘌呤氧化酶体系产生的超氧阴离子及紫外线照射H_2O_2体系产生的羟自由基均有显著清除作用。提示生姜对活性氧的清除可能是其重要的药理机制之一。

药物荧光分析法研究进展

简要概述了药物分析中荧光分析法的研究现状、应用前景和发展趋势 ,特别评介了药物荧光分析中的表面活性剂增溶增敏作用及其机理、包络作用及其机理。

Al^(3+)-芦丁二元络合物荧光光度法测定银杏叶中总黄酮的含量

根据黄酮类化合物能与Al3+形成稳定的荧光络合物,以芦丁为标样,建立了一种测定银杏叶总黄酮的荧光分光光度法。激发波长λex=436 nm,发射波长λem=483nm,方法检出限为1.27×10-9 mol·L-1,线性范围在1.64×10-9~3.63×10-5 mol·L-1之间,回收率为99.8%~104.2%,相对标准差(RSD)为1.94%。

荧光光度法测定银杏叶总黄酮含量的研究

目的:根据黄酮类化合物能与Al3+形成稳定的荧光络合物,建立一种测定银杏叶总黄酮的新方法。方法:用60%乙醇加热回流提取银杏叶有效成分,以芦丁为标样,采用荧光分光光度法,选择激发波长λex=436nm,发射波长λem=483nm,测定银杏叶中总黄酮含量,并进行加标回收实验,验证方法的准确性。结果:本方法检出限为1.27×10-9mol·L-1,线性范围在1.64×10-9～3.63×10-5mol·L-1之间,线性回归方程:Y=1.9313X+0.2705,相关系数r=0.9989,平均回收率99.8%～104.2%,相对标准差(RSD)1.94%。结论:本法操作简便、快速、准确,具有良好的分析应用前景。

多沙唑嗪与血清白蛋白的作用及血清中多沙唑嗪含量的荧光测定法研究

用荧光光度法研究了降血压药物多沙唑嗪(doxazosin)与血清白蛋白的相互作用,求得不同温度下药物与血清白蛋白相互作用的形成常数;讨论了微量金属离子对药物与血清白蛋白形成常数的影响,并根据热力学常数确定了该药物与血清白蛋白之间的作用力类型为疏水作用力;研究了测定多沙唑嗪的适宜条件并成功应用于血样中含量的测定.

洛美沙星-Tb^(3+)配合物与BSA相互作用的荧光光谱研究

以洛美沙星-Tb3+作为荧光探针,利用荧光光谱研究了洛美沙星-Tb3+配合物与BSA的相互作用。实验发现牛血清白蛋白与洛美沙星分子之间有较强的结合作用,而且洛美沙星对BSA的构象有一定的影响;同时BSA与Tb3+之间存在静电作用,可置换出配合物中的水分子,使体系的荧光强度增强。结果表明在实验最佳条件下,牛血清白蛋白能增强洛美沙星-铽的荧光强度,据此建立了一种检测白蛋白的新方法,该法的检测限可达ng水平,线性范围为16.5~148.5μg.mL-1,检测限为68.8ng.mL-1,RSD为1.4%。此法简便易行,而且不受共存物质的干扰。

2,3,4-三羟基苯乙酮缩-2-羧基苯胺与铜的高灵敏度荧光反应及其应用

合成了新荧光试剂 2 ,3,4 三羟基苯乙酮缩 2 羧基苯胺 (TAFA)。详细研究了试剂与铜的荧光反应新体系的最佳适宜条件。在 pH 9.0的乙醇 /水 (3.5∶6 .5 ,V/V)溶液中 ,该试剂与铜离子形成稳定的络合物 ,组成比为 1∶1(金属∶试剂 ) ,λex/em=4 2 2 .4 / 5 6 1.6nm。所建立的铜的荧光分析方法的线性范围为 0 .5～ 12 0 .0μg/L ;检出限为 0 .2 6 μg/L。方法成功地应用于矿泉水和水中痕量铜的测定。

荔枝皮黄酮抑菌性能及其作用机理研究

采用荧光分析法测定荔枝皮中总黄酮含量,并研究了荔枝皮黄酮对常见4种微生物的抑菌活性及机理。结果表明,其黄酮纯度与得率分别为48%和13.61%;同时,采用牛津杯法测得荔枝皮黄酮对金黄色葡萄球菌、大肠杆菌和酵母菌的抑菌圈直径分别为15.1、14.0和13.8 mm;采用菌饼法测得对黑曲霉的抑菌率为28.75%。采用平板稀释法测得金黄色葡萄球菌和大肠杆菌的最低抑菌浓度MIC为2.5 mg/mL,最低杀菌浓度MBC为5mg/mL,而酵母菌和黑曲霉的MIC为5 mg/mL,没有杀菌能力。扫描电镜实验结果表明,荔枝黄酮的抑菌性和杀菌功能与其对金黄色葡萄球菌细胞和细胞壁结构的破坏直接相关。

荧光光度法测定雨水中的H_2O_2含量

研究了在pH4.48的HAc-NaAc缓冲溶液中,邻苯二胺(OPDA)与过氧化氢反应生成新物质2,3-二氨基吩嗪(DAPN)的荧光光谱变化,通过跟踪DAPN的荧光强度建立了过氧化氢测定的新方法,该方法由于采用二元体系,实验操作简单,灵敏度较高。实验结果表明,过氧化氢含量在9.0×10-7～3.6×10-5mol.L-1范围内与荧光强度的变化呈良好的线性关系,线性方程为:F=1.15c(μmol.L-1)+398.6,相关系数r=0.9991,最低检出限为2.7×10-7mol.L-1(3Ds/斜率,n=11)。对含量为7.5×10-6mol.L-1和3.0×10-5mol.L-1的H2O2的标准溶液进行了11次平行测定,其相对标准偏差分别为2.2%和1.0%。考察了多种共存离子的影响。该方法用于雨水中微量H2O2的测定,测定结果令人满意。

核酸-8-羟基喹啉-钪(Ⅲ)体系的荧光特性及其分析应用

在ＰＨ ６．８～８．８的酸度范围内，小牛胸腺脱氧核糖核酸（ｃｔＤＮＡ），鱼精子脱氧核糖 核酸（ｆｓＤＮＡ）以及酵母核糖核酸（ｙＲＮＡ）分别与８－羟基喹啉（８－ＨＱＬ）和Ｓｃ（Ⅲ）形成的三元 体系受 ２６４～２７０ ｎｍ紫外光激发将发出 ４９０～４９６ ｎｍ的荧光。与 Ｓｃ（Ⅲ）和 ８－ＨＱＬ 二元络合 物相比，三元体系的荧光量子产率增大，荧光寿命增长，最大发射波长紫移约 １０ ｎｍ。６个合 成样品的分析结果表明，利用 Ｓｃ（Ⅲ）／８－ＨＱＬ能十分灵敏的测定脱氧核糖核酸。

米糠中阿魏酸的提取及荧光分光光度法检测

确定了新鲜米糠中阿魏酸的最佳提取工艺。采用高效液相色谱法对提取产品的定性检测,荧光分光光度法对提取产品的定量检测。阿魏酸在0.2～2.2μg/ml浓度范围内呈良好的线性关系,相关系数为0.99957,平均回收率为99.0%。此法具有准确、简便、快速、灵敏等优点。