Determination of Rutin in Plant Extracts and Emulsions by HPLC-MS

A method for the determination of rutin was developed from in an O/W emulsion with decyl oleate and Ceteareth-20 containing Ginkgo biloba L., Hedera helix L., and Thymus vulgaris L. extracts. Total quantification of rutin was performed by determination in the aqueous and oily phase. Rutin was extracted from the oily phase by ultrasonication for 30 min at 37°C in methanol and resolved by liquid chromatography on a column containing a Gemini 3 µ C18 110A stationary phase.

Chromatography was carried out using gradient elution with the mobile phase composed of water:formic acid and water:acetonitrile:formic acid, which was varied from 100:0.1 to 50:50:0.1 (v/v/v) over 80 min and delivered at a flow rate of 0.3 ml/min. The analytes were quantified using a UV-VIS absorption spectrometer at a wavelength of 254 nm and a single quadrupole mass spectrometer employing an ESI interface operated in the positive ion mode with single ion monitoring at m/z = 609.14.

Finally, a simple and rapid method for the extraction and determination of rutin in hydrophilic and lipophilic phases of an O/W emulsion with good precision and acceptable recovery was developed. This method might be of special importance for the analysis of rutin and other flavonoids in O/W or W/O emulsion matrices.     

Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae

Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction (SMOBE). The third procedure was microwave resonant cavity dynamic extraction (MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other.     

槲皮素和芦丁与牛血清白蛋白相互作用研究

本文用荧光光谱法研究了槲皮素、芦丁与牛血清白蛋白(BSA)的相互作用,确定槲皮素、芦丁对BSA的荧光猝灭类型是静态猝灭,并计算出不同温度下槲皮素、芦丁与BSA的结合常数,由热力学参数确定它们间主要是疏水作用力,并依据F ster能量转移原理求得其结合距离及能量转移效率,探讨了小分子-蛋白质作用规律。     

小波变换分光光度法同时测定复方芦丁片中芦丁和维生素C

建立了同时测定复方芦丁片中芦丁和维生素C含量的计算分光光度法--小波变换分光光度法.对芦丁和维生素C的重叠吸收光谱进行连续小波变换,分别提取只与芦丁和维生素C有关的特征小波变换系数,由特征小波变换系数值和浓度建立的线性回归方程,可以准确地测定复方芦丁片中芦丁和维生素C的含量.芦丁和维生素C的线性范围分别为0～25 mg·L-1和0～15 mg·L-1,对3个模拟试样作回收率和精密度试验,回收率在98.1%～102.0%之间,RSD值均小于等于0.9%.     

微波辅助萃取鬼箭羽叶中芦丁和槲皮素

建立了鬼箭羽中主要有效成分芦丁和槲皮素的MAE-HPLC定量分析方法, 该方法具有测定准确、操作简便和分析速度快等优点. 此外, 利用扫描电镜观察了鬼箭羽叶经微波辅助萃取后植物结构的变化, 初步证明了微波辅助萃取鬼箭羽叶的萃取机理符合细胞破壁学说.     

毛细管区带电泳电化学检测法测定药物及果汁中芦丁和L-抗坏血酸

用毛细管区带电泳-电化学检测法同时测定复方芦丁片及果汁中芦丁和L-抗坏血酸的含量.研究了电极电位、电解液浓度和酸度、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1.0V(vs.SCE),在25mmol/L硼砂-50mmol/LNaH₂PO₄(pH8.0)运行缓冲液中,上述两组分在12min内完全分离.芦丁和L-抗坏血酸浓度分别在1.0×10^-6～2.5×10^-4和5.0×10^-6～2.5×10^-3mol/L范围内与电泳峰电流呈现良好线性关系,检测下限分别为8.0×10^-7和3.3×10^-6mol/L.9次测定含5.0×10^-5mol/L芦丁和2.5×10^-4mol/LL-抗坏血酸的试样溶液,峰高的相对标准偏差分别为2.85%和1.65%,5次测得的平均回收率分别为97.73%和99.68%.     

双波长叠加法测定样品中槲皮素含量

在pH= 7.45的B-R缓冲介质中,槲皮素在256 nm和368 nm波长处有两个强度不等的吸收峰,实验发现两个峰的吸光度值之和与槲皮素的浓度呈良好的线性关系,据此提出了双波长叠加分光光度法测定微量槲皮素的新方法.槲皮素的质量浓度在0.84～42 μg· mL-1范围内符合比耳定律,表观摩尔吸光系数高达4.24×10...     

Spectrophotometric Determination of Certain Local Anaesthetics in Pharmaceutical Preparations

Abstract

A direct colorimetric method was described for the rapid, sensitive and accurate determination of dibucaine, lidocaine, bupivacaine, procaine and tetracaine in pharmaceutical preparations. The method involves the use of haematoxylin reagent in the presence of boric acid to give a reddish-violet chromogen (λ_max = 555 nm). Beer's law was obeyed in the range from 2–60 μg/ml. No interference was observed from the commonly present additives or agents in pharmaceutical formulations.     

Simultaneous Spectrophotometric Determination of Hydrochlorothiazide and Pharmaceutical Preparations

Abstract

We developed three methods for the simultaneous determination of amiloride (AMI) and hydrochlorothiazide (HCT): zero-crossing, derivative quotient spectra with normalized divisor and multiple linear regression (MULTIC) methods. The two first methods use the derivative spectrophotometry, and the last one uses the absorbance measurement. The three methods were used to determine both compounds in synthetic mixtures and pharmaceutical preparations with errors less than 5% and 15%, respectively.     

Determination of Rutin in Pharmaceutical Compounds and Tea Using Cathodic Adsorptive Stripping Voltammetry

A new sensitive electrochemical procedure is presented for the determination of Rutin based on the accumulation of Rutin onto the surface of hanging mercury drop electrode for 80 s. Then the preconcentrated Rutin‐complex was analyzed by cathodic stripping square‐wave voltammetry. The effect of various parameters such as pH, concentration of copper, accumulation potential, accumulation time and scan rate on the sensitivity were studied. The optimum conditions for determination of Rutin include pH 6.0, 6.0 ng mL^?1 copper(II) concentration, accumulation potential of ?0.30 V and scan rate of 0.40 V s^?1. Under the optimum conditions and for an accumulation time of 80 s, the measured peak current at about ?0.03 V is proportional to the concentration of Rutin over the range of 2.0–85.0 nM. The practical limit of detection is 0.5 nM. The relative standard deviations for six replicate analyses of 10 and 50 nM Rutin are 1.8% and 1.7%, respectively. The method was applied to the determination of Rutin in synthetic, tea, and pharmaceutical samples with satisfactory results. The diffusion coefficient, complex formation constant and number of electron transfer of Rutin–Cu(II) complex was also estimated.     

槲皮素荧光光度测定法的研究

本详细研究了表面活性剂十二烷基磺酸钠存在下，槲皮素与锆形成三元荧光光胶束配的条件，并建立了测定槲皮素的荧光光度法。在０．９ｍｏｌ／Ｌ盐酸介质中，槲皮素与锆（Ⅳ），ＳＬＳ形成１：４：４的黄绿色荧光配合物，激发波长４３２。１ｎｍ，发射波长５０１。３ｎｍ，线性范围为０．３０×１０－６－１．１１×１０－５ｍｏｌ／Ｌ，检测限为３．７９×１０－７ｍｏｌ／ Ｌ。所拟方法用于芦丁酸水解产物的测定及槐花中回收率的     

On the Ligand‐to‐Metal Charge‐Transfer Photochemistry of the Copper(II) Complexes of Quercetin and Rutin

In contrast to the UV‐photoinduced ligand photoionization of the flavonoid complexes of Fe^III, redox reactions initiated in ligand‐to‐metal charge‐transfer excited states were observed on irradiation of the quercetin ( 1 ) and rutin ( 2 ) complexes of Cu^II. Solutions of complexes with stoichiometries [Cu^IIL₂] (L=quercetin, rutin) and [Cu^II₂L_n] (n=1, L=quercetin; n=3, L=rutin) were flash‐irradiated at 351 nm. Transient spectra observed in these experiments showed the formation of radical ligands corresponding to the one‐electron oxidation of L and the reduction of Cu^II to Cu^I. The radical ligands remained coordinated to the Cu^I centers, and the substitution reactions replacing them by solvent occurred with lifetimes τ<350 ns. These are lifetimes shorter than the known lifetimes (τ>1 ms) of the quercetin and rutin radical's decay.     

Determination of Rutin in Amaryllis belladonna L. Flowers by HPTLC and Spectrophotometry

The work presented in this paper demonstrates the use of HPTLC-UV to quantify rutin in the alcoholic extract of Amaryllis belladonna L. (Family Amaryllidaceaea) flowers which was detected, isolated and identified in previous work. The results obtained by HPTLC showed excellent accuracy and precision when compared to the spectrophotometric method.     

A Stability-Indicating Spectrophotometric Method for the Determination of Fenoterol in Pharmaceutical Preparations.

ABSTRACT

A simple and highly sensitive spectrophotometric method was developed for the determination of fenoterol hydrobromide in pharmaceutical formulations. The method is based on measurement of the orange-yellow color peaking at 436 nm, produced when the drug is coupled with diazotized benzocaine in triethylamine medium. The method is applicable over the range of 0.5 – 10 μg/ml, with minimum detectability of 3.6 ng/ml (≈ 9.4×10^?9 M). The molar absorptivity is 4.61×10⁴ L. mol^?1. cm^?1. with relative standard error of 0.196%. The proposed method was successfully applied to the determination of fenoterol in its dosage forms; the mean recoveries of 99.61 ± 1.59 and 98.97 ± 1.52 for tablets and aerosols, respectively, were obtained. The results of the proposed method were favorably compared to those obtained by the official and reference methods. No i8543168 was encountered from the co-formulated drug ipratropium bromide, common excipients and alkaline induced degradation product. A proposal of the reaction pathway is presented.     

示波极谱滴定法测定芦丁中总槲皮素含量

以K2CrO4与槲皮素的直接氧化还原反应为基础,用pH 8.0的1.5 mol/LNH4Ac-NH4OH为示波极谱底液,并根据示波极谱图上CrO42-切口出现以指示滴定终点,建立了测定药物制剂芦丁中总槲皮素含量的分析方法。本法简便、快速、准确,标准加入平均回收率为98.50%,RSD为0.41%。     

毛细管区带电泳法研究不同炮制方法对槐花、槐米中芦丁和槲皮素含量的影响

建立了一种毛细管区带电泳(CZE)法测定芦丁和槲皮素的方法,利用该方法研究了不同炮制方法对槐花、槐米中芦丁和槲皮素含量的影响。研究了缓冲溶液pH和浓度、分离电压、有机添加剂的浓度和进样时间对分离的影响,在优化条件下,上述两种物质在5 min内实现良好分离。芦丁和槲皮素峰面积和质量浓度分别在0.04~1.8和0.02~2.0 g.L-1浓度范围内呈线性关系,线性相关系数分别为0.999 2和0.999 4,检出限分别为8和5 mg.L-1。试验结果表明,炮制方法影响槐花和槐米中芦丁、槲皮素的含量。     

流动注射化学发光法测定槐米中槲皮素

在碱性溶液中槲皮素对过氧化氢氧化鲁米诺而产生的化学发光(CL)具有很强的抑制作用,且其CL强度的减弱程度与槲皮素浓度之间在一定的范围内呈线性关系。据此,并结合应用流动注射(FI)技术,提出了FI-CL测定槐米中槲皮素含量的方法。反应体系中所用试剂的最佳浓度为:①cH2O2=0.2mol.L-1;②c鲁米诺=8.5×10-4mol.L-1;③cNaOH=0.01mol.L-1。对槲皮素测定的线性范围为2.65×10-6～5.31×10-4mol.L-1之间,其检出限(3s/k)为9.26×10-7mol.L-1。用4×10-4mol.L-1槲皮素标准溶液进行精密度试验,测得相对标准偏差(n=11)为3.0%。分析试样时,先从槐米在pH 8～9的碱性溶液中提取芦丁,然后在微酸性(pH 5)溶液中使芦丁水解得到槲皮素粗品。将此粗品经反复重结晶得到槲皮素纯品,溶于乙醇(40+60)溶液中制成溶液,用于FI-CL分析。     

Development and Validation Method for Silica Determination by Spectrophotometry in Some Herbs and Pharmaceutical Formulations

ABSTRACT

A spectrophotometric method for determination of silica in herbs and herbal pharmaceutical products has been developed and validated. The method showed excellent accuracy and precision with S.D. 1.67 and RSD 1.72%, 2.75%, respectively. The established linearity range was 0.05–0.5 μg/mL(r² > 0.99974). The recovery of silica from spiked placebo was > 95% over the linear range. The method has been successfully used in the analysis of silica in raw material and herbal pharmaceutical formulations. This validated method proved to be rapid and less costly.     

苦荞叶片中芸香甙的薄层色谱定量研究

根据芸香甙的理化性质，建立了一种测定植物样品中芸香甙含量的薄层紫外扫描法，采用硅胶ＧＦ２５４薄层板，样品经甲醇提取浓缩后点样，展开剂为乙酸乙酯－甲酸－水（８＋１＋１）。用薄层色谱扫描仪在波长３５５ｎｍ处测定芸香甙的吸收强度并直接定量。该法操作简便，灵敏度高，定量准确，结果稳定，应用于苦荞叶片中芸香甙含量测定，得到良好结果，线性范围为０～２．０μｇ／μＬ，斑点的最低检出限为５．０ｎｇ，回收率１０２％     

流动注射化学发光分析法测定芸香苷

基于芸香苷对鲁米诺－过氧化氢－铬化学发光体系的抑制作用，首次建立了芸香苷的化学发光抑制分析法。发光信号的降低值ΔＩ与芸香苷的质量浓度在２．０×１０－８～１．０×１０－５ｇ／ｍＬ的范围内呈线性关系，检出限为７．０×１０－９ｇ／ｍＬ（ｎ＝１１）。该法可用于中药槐花中芸香苷的定量分析。