高效液相色谱法测定食品中的香豆素

介绍了用反相高效波相色谱（RP－HPLC）测定食品中香豆素含量的方法。样品用无水乙醚萃取,在40℃水浴上用氮气吹干,残留物用V（甲醇）：V（水）=9：1反萃取,用RP－HPLC定量分析。方法最小检出限为0.015mg／L,在2～10mg／L范围内有良好的线性关系,测定准确、重现性好,回收率为97.6％～100．8％,方法可行。     

HPLC-ICP-MS或HPLC-FAAS法分离测定硒化合物（英文）

 提出了一种用高效液相色谱（HPLC）分离和用电感偶合等离子体质谱仪（ICP－MS）或火焰原子吸收光谱仪（FAAS）作元素专一检测器在线测定硒的化学形态的方法。在优化的HPLC条件下,用ESAⅢ阴离子色谱柱（250mm×4．6mm）,以柠檬酸铵为流动相（5．5mmol／L,pH5．5,流速1．5mL／min）,进样量100μL,分离和测定三甲基硒离子、硒代蛋氨酸、亚硒酸和硒酸盐只需8min。HPLC－FAAS在线分析4种硒化合物的检测限为p（Se）=1mg／L。     

高效液相色谱法测定“龙牡壮骨冲剂” 中β-环糊精包合的维生素D2

 用反相高效液相色谱法（HPLC）和紫外分光光度法 （UV）测定了β-环糊精（β-CD）与维生素D2（VD2）包 合物中VD2的质量分数,两种方法测得的结果十分吻合。研究了HPLC测定的精密度和回收 率,其相对标准偏差分别为0.63%和1.54%,表明该法准确可靠。含有β-CD-VD2包合物的“龙牡壮骨冲剂”经KOH、维生素C和乙醇-水（体积比为1∶2 ）于70 ℃下皂化处理,再由HPLC检测用乙醚萃取的VD2产物,得到准确的结果。 关键词：     

大蒜新素二烯丙基三硫化合物的化学分析

用氧瓶燃烧法，对合成得到的大蒜新素二烯丙基三硫化合物（V），进行了元素硫定量分析，测定结果与HPLC方法数据基本一致，相对标准偏差为0.23%。     

智子颗粒剂降血铅的临床疗效观察

应用中药智子颗粒剂（方剂组成：枸杞子，益智仁，煅牡蛎，牛磺酸）预防，治疗铅暴露导致儿童亚临床神经毒性，其方法：在一定区域内对年龄７～１２岁小学生共３９９名进行血铅测定，其中血铅值〉２０μｇ／ｄＬ（０．９６５ｕｍｏｌ／Ｌ）１６名，随机分为给药组，对照组各６０名，开放组４２名，用药前后进行血红蛋白，身长，体重，视力测定，并在给药组中给药前后进行血液生化及免疫学检查（ＡＬＴ，ＡｓｔＢｕｎ，Ｃｒ，ＩｇＧ，     

苯溴马隆及其杂质的质量研究

建立了用HPLC和TLC两种方法测定新药苯溴马隆的杂质限量，以确保药物的质量，用反相HPLC法，ODS柱，甲醇－水－冰醋酸（88：12：2．5）（PH3．5）为流动相，检测波长254nm，流速1．0mL/min，分离出两种主要杂质，其结构已确证，在国内外文献中均未见报道。在制定苯溴马隆质量标准中，已将所建立RPHPLC法，作为该药物质的测定方法。     

HPLC-ICP-MS或HPLC-FAAS法分离测定硒化合物（英文）

提出了一种用高效液相色谱（HPLC）分离和用电感偶合等离子体质谱仪（ICP－MS）或火焰原子吸收光谱仪（FAAS）作元素专一检测器在线测定硒的化学形态的方法。在优化的HPLC条件下,用ESAⅢ阴离子色谱柱（250mm×4．6mm）,以柠檬酸铵为流动相（5．5mmol／L,pH5．5,流速1．5mL／min）,进样量100μL,分离和测定三甲基硒离子、硒代蛋氨酸、亚硒酸和硒酸盐只需8min。HPLC－FAAS在线分析4种硒化合物的检测限为p（Se）=1mg／L。用超声雾化器作ICP－MS的接口,HPLC－ICP－MS在线分析4种硒化合物的检测限分别为P（Se）=0．34μg／L（亚硒酸）,0．18μg／L（硒代蛋氨酸）,0．08μg／L（三甲基硒离子）和0．07μg／L（硒酸盐）。与气动雾化器接口相比,信号强度增加7至31倍。     

高效液相色谱-荧光法测定人血浆中米多君及其代谢物去甘氨酸米多君

1引言 米多君（MD）是一种拟交感胺，临床主要用于治疗低血压症。米多君为一种前体药，本身无活性，在体内代谢为具有较强选择性外周α-受体激动作用的去甘氨酸米多君（去-MD）。米多君及其代谢物去甘氨酸米多君血药浓度测定法，文献报道有HPLC—MS和荧光法等。但它们只测定了单一组分浓度（米多君或去甘氨酸米多君）；本研究优化并建立了反相高效液相色谱．荧光法同时测定血浆样品中米多君及其代谢物去甘氨酸米多君的浓度。     

GC-MS测定体内盐酸埃他卡林及药代动力学研究

盐酸埃他卡林具有新颖、独特的抗高血压作用,国家科技部将其列入1035工程重点研究项目.由于该药化学结构及理化性质的特殊性,无法用HPLC及GC等常规方法进行体内药物浓度测定,且该药与多种常用的衍生化试剂难以进行反应,给药代动力学研究带来很大的困难.本文旨在建立灵敏、专一的体内微量药物定量分析方法,评价该药在动物体内的药代动力学性质,保证临床安全合理用药.     

双带药的高效液相色谱分析法

 ]本文叙述了用反相高效液相色谱法分离分析双带药乙醚提取液中硝化甘油和中定剂的方法，以GYT-CH（10μm）为固定相，装入150mm×φ4mm的不锈钢管内，使用甲醇：水（70:30，V/V）作流动相，苯作内标，UV检测器的检测波长为230nm。在几分钟内成功地定量测定了双带火药中硝化甘油和中定剂的含量，并对波长与流动相的选择进行了讨论，测定的方法已满足了部颁标准的要求，并达到了国外同类HPLC分析方法的准确度和精密度。     

Simultaneous quantitative estimation of oxybenzone and 2-ethylhexyl-4-methoxycinnamate in sunscreen formulations by second order derivative spectrophotometry

Simultaneous determination of 2-ethylhexyl-4-methoxycinnamate (OMC) and oxybenzone (OB) in commercial sunscreen formulations has been achieved by using second order derivative spectrophotometry. The analytical methodology described does not require elaborate pretreatment of samples. The results obtained could be validated by reverse phase HPLC assay by using isocratic methanol: water (88: 12) solvent system. The sensitivity of the developed derivative spectrophotometry method was determined to be 9.0 × 10⁻³ L/mg for OB and 9.56 × 10⁻³ L/mg for OMC. The limit of instrumental detection (LOD) was determined to be 0.6 mg/L for OB and 1.38 mg/L for OMC with relative standard deviation of 0.001 and 0.004 for OB and OMC respectively. The method developed can be used for quick assay of commercial sunscreens. The article is published in the original.     

Spectrophotometric and AAS determination of trace amounts of cobalt after preconcentration by using alpha-benzilmonoxime-microcrystalline naphthalene.

The formed cobalt-a-benzilmonoxime complex was adsorbed onto microcrystalline naphthalene. Then it was determined by zero and first derivative spectrophotometry and by atomic absorption spectrophotometry (AAS) after dissolving into chloroform and methylisobutylketone (MIBK), respectively. Under optimum conditions, cobalt in the range of 1.0 - 20.0, 0.4 - 30.0 and 2.5 - 50.0 microg could be determined by spectrophotometry, first derivative spectrophotometry and AAS method, respectively. By the method, a preconcentration factor equal to approximately 30 for cobalt was obtained. The effect of diverse ions on the determination of 5.0 microg cobalt was also studied. The method was successfully applied to some pharmaceuticals and synthetic alloy samples.     

Determination of astaxanthin in Haematococcus pluvialis by first-order derivative spectrophotometry

A highly selective, convenient, and precise method, first-order derivative spectrophotometry, was applied for the determination of astaxanthin in Haematococcus pluvialis. Ethyl acetate and ethanol (1:1, v/v) were found to be the best extraction solvent tested due to their high efficiency and low toxicity compared with nine other organic solvents. Astaxanthin coexisting with chlorophyll and beta-carotene was analyzed by first-order derivative spectrophotometry in order to optimize the conditions for the determination of astaxanthin. The results show that when detected at 432 nm, the interfering substances could be eliminated. The dynamic linear range was 2.0-8.0 microg/mL, with a correlation coefficient of 0.9916. The detection threshold was 0.41 microg/mL. The RSD for the determination of astaxanthin was in the range of 0.01-0.06%; the results of recovery test were 98.1-108.0%. The statistical analysis between first-order derivative spectrophotometry and HPLC by T-testing did not exceed their critical values, revealing no significant differences between these two methods. It was proved that first-order derivative spectrophotometry is a rapid and convenient method for the determination of astaxanthin in H. pluvialis that can eliminate the negative effect resulting from the coexistence of astaxanthin with chlorophyll and beta-carotene.     

Comparison of Chemometric and Chromatographic Methods to Obtain Kinetic Parameters for Textile Dyes during a Biodegradation Process

The concentrations of three industrial-grade textile dyes were determined in a mixture after degradation by the fungus Ganoderma sp, by using the methods of UV-Vis spectrophotometry associated with Partial Least Squares regression and HPLC and comparing the results obtained from both methods. Using the concentrations calculated from the two methods, a kinetic study of the biodegradation mediated by the fungus was performed. The rate constants and the activation energies for this transformation were obtained for each dye in the mixture. The concentration of Remazol Blue R ESP could be determined by the HPLC method, and the value obtained was comparable with the result using the Partial Least Squares regression method. The Partial Least Squares regression method offers advantages over the HPLC method for the quantification of dyes in textile effluents, as it provides the kinetic parameters of the biodegradation reaction.     

Comparative Spectrophotometric,Spectrofluorometric, and High‐performance Liquid Chromatographic Study for the Quantitative Determination of the Binary Mixture Felodipine and Ramipril in Pharmaceutical Formulations

Abstract

Two‐component mixtures of felodipine (FLD) and ramipril (RMP) were assayed by derivative UV spectrophotometry, spectrofluorometry, and high performance liquid chromatography (HPLC). The spectrophotometric methods included a zero‐crossing first‐ and second‐order derivative procedure and a derivative compensation technique for the determination of binary mixtures with overlapping spectra. The spectrofluorometric method was based on first‐ and second‐order derivatives of the emission spectra (zero‐crossing point). Results from these methods were compared with those obtained by an exclusively developed isocratic reversed phase HPLC method. A reversed‐phase Adsorbosil DS analytical column, with methanol‐acetonitrile‐water (50∶30∶20, v/v) mobile phase at a flow rate of 1.5 ml/min, was used with a UV detector. The temperature was set at 25±0.2°C. Results obtained by the spectrophotometric and spectrofluorometric methods were comparable to those obtained by the HPLC method, as far as analysis of variance (ANOVA) test results were concerned. It is concluded that the developed methods are equally accurate, sensitive, and precise; with direct and simple application to pharmaceutical formulations of felodipine and ramipril combination, without interference from common pharmaceutical adjuvants.     

Development and Validation of HPLC,TLC and Derivative Spectrophotometric Methods for the Analysis of Ezetimibe in the Presence of Alkaline Induced Degradation Products

Reversed phase‐high performance liquid chromatography (RP‐HPLC), thin layer chromatography (TLC) densitometry and first derivative spectrophotometry (1D) techniques are developed and validated as a stability‐indicating assay of ezetimibe in the presence of alkaline induced degradation products. RP‐HPLC method involves an isocratic elution on a Phenomenex Luna 5μ C₁₈ column using acetonitrile: water: glacial acetic acid (50:50:0.1 v/v/v) as a mobile phase at a flow rate of 1.5 mL/min. and a UV detector at 235 nm. TLC densitometric method is based on the difference in Rf‐values between the intact drug and its degradation products on aluminum‐packed silica gel 60 F₂₅₄ TLC plates as stationary phase with isopropanol: ammonia 33% (9:1 v/v) as a developing mobile phase. On the fluorescent plates, the spots were located by fluorescence quenching and the densitometric analysis was carried out at 250 nm. Derivative spectrophotometry, the zero‐crossing method, ezetimibe was determined using first derivative at 261 nm in the presence of its degradation products. Calibration graphs of the three suggested methods are linear in the concentration ranges 1–10 mcg/mL, 0.1–1 mg/mL and 1–16 mcg/mL with a mean percentage accuracy of 99.05 ± 0.54%, 99.46 ± 0.63% and 99.24 ± 0.82% of bulk powder, respectively. The three proposed methods were successfully applied for the determination of ezetimibe in raw material and pharmaceutical dosage form; the results were statistically analyzed and compared with those obtained by the reported method. Validation parameters were determined for linearity, accuracy and precision; selectivity and robustness and were assessed by applying the standard addition technique.     

Determination of phenylephrine hydrochloride and chlorpheniramine maleate in binary mixture using chemometric-assisted spectrophotometric and high-performance liquid chromatographic-UV methods

Four methods have been developed for the simultaneous determination of phenylephrine hydrochloride and chlorpheniramine maleate without previous separation. In the first method both drugs are determined using first derivative UV spectrophotometry, with zero-crossing measurement. The second method depends on first derivative of the ratios spectra. The third method describes the use of multivariate spectrophotometric calibration for the simultaneous determination of the analyzed binary mixture where the resolution is accomplished by using partial least squares (PLS) regression analysis. In the fourth method (HPLC), a reversed-phase column and a mobile phase of methanol:water:acetonitrile (80:12:8 v/v/v/) at 0.9 ml/min flow rate have been used to separate both drugs with a UV detection at 270 nm. All the proposed methods are extensively validated. They have the advantage to be economic and time saving. All the described methods can be readily utilized for analysis of pharmaceutical formulations. The results obtained using the proposed methods are statistically analyzed and compared with some reported methods.     

A New Absorbance Ratio Derivative Spectrophotometry for the Simultaneous Determination of a Binary Mixture Containing Phenol and Resorcin

It is the most important problem of spectrophotometric analysis to determine two or more components in the same sample simultaneously without previous separation. In this respect, the absorbance derivative spectrophotometry is an analytical technique of great utility and offers greater selectivity than normal spectrophotometry. Recently, Salinas et al developed the absorbance ratio derivative spectra. The absorption spectrum of the mixture is divided by the absorption spectrum of a standard solution of one of the two or more components, and the first derivative of the ratio spectrum is obtained. The concentration of active component is then determined from a calibration graph obtained by measuring the amplitude at point corresponding to the minimum or maximum wavelength. In this way, the sensitivity of method is greatest.     

Validation of an analytical method to quantify the permeation and penetration of flurbiprofen into human pharynx tissue

The aim of this investigation was to develop receiver and extraction fluids, and subsequently validate an analytical method to quantify the permeation and penetration of flurbiprofen into human pharynx tissue using a Franz diffusion cell. The solubility and stability of flurbiprofen in a suitable receiver fluid, and a suitable extraction method and fluid to recover and quantitate flurbiprofen from human pharynx tissue, were investigated using high‐performance liquid chromatography (HPLC). The potential interference of human pharynx tissue in the receiver fluid was also investigated. The HPLC analytical method was successfully validated according to current guidelines. The final receiver fluid demonstrated sufficient solubility and stability, and the extraction method and fluid resulted in >95% recovery of flurbiprofen following exposure to human pharynx tissue. The lower limit of quantitation of flurbiprofen was 0.045 μg/mL in both the receiver and extraction fluids. There was no interference of the human pharynx tissue with the HPLC method. This investigation validated an analytical method for quantitating flurbiprofen, and determined a suitable receiver fluid and extraction method and fluid, which can be used to investigate the permeation and penetration of flurbiprofen through human pharynx tissue using the Franz diffusion cell method.     

紫外及导数吸收光谱法直接测定钕铁合金中铁和谱、钕

钕铁合金是用于制备Nd-Fe-B永磁体的材料,在它的生产中需要测定铁和镨、钕,迄今尚未见有简便分析方法的报导。常规吸收光谱法测定镨、钕的灵敏度低、对低含量镨更难满足要求,笔者之一曾用稀土高氯酸溶液的三阶导数光谱法测定了镨钐钴合金及钇铝石榴石等样品中大量或少量单一稀土元素,取得了满意的结果。文献曾报导用铁的高氯酸溶液紫外光谱法测定铁,但未见广泛应用,且未见大量错、钦对铁的测定的影响的报导。本文结果表明,在高氯酸溶液中用三阶导数光度法可同时测定错和钦,共存大量铁无干扰,分取同一样品溶液稀释后可用紫外光谱法测定铁,错、按对铁的测定无影响,从而一次溶样即可达到测定错、钦和铁的目的,方法简便、快速而且准确。