高效液相色谱法测定苹果汁中8种酚类化合物

提出了高效液相色谱法同时测定苹果汁中儿茶素、绿原酸、咖啡酸、表儿茶素、香豆酸、阿魏酸、槲皮素和根皮素等8种酚类化合物的方法,并考察了光照、保存时间等因素对酚类化合物的稳定性的影响.选用Eclipse XDB C18色谱柱(150 mm×4.6mm,5μm),以甲醇和乙酸-水(1+99)溶液作为流动相进行梯度洗脱,利用二极管阵列检测器,在各种酚类物质的最大吸收波长下进行紫外光度检测.对各化合物工作曲线的线性范围作了试验,并推导得到相应的线性回归方程,其相关系数均为0.999 9,在苹果汁样品的基础上用标准加入法各进行7次测定,测得平均回收率均在96.0%～100.8%之间,相对标准偏差(n=7)小于等于3.0%,8种化合物的检出限(3S/N)分别为20,10,4,20,5,8,30和7μg·L-1.     

反相高效液相色谱分离-安培法检测酚类化合物

本文报道了RP-HPLC-安培法检测测定酚类化合物的条件。在Shim-pack CLC-C_8柱上用含0.05mol/L NaH_2PO_4缓冲溶液的5％甲醇水溶液洗脱分离,于E+1.0V处检测。线性范围在0～7μg/ml,检测限达ng/ml。     

GDX树脂富集－反相高效液相色谱法分离测定酚类化合物

 用ＧＤＸ－５０２树脂富集的酚类化合物，经反相高效液相色谱法分离和检测，具有较好的准确度和精密度。     

GDX树脂富集－反相高效液相色谱法分离测定酚类化合物

用ＧＤＸ－５０２树脂富集的酚类化合物，经反相高效液相色谱法分离和检测，具有较好的准确度和精密度。     

反相高效液相色谱法测定蜂胶水提物中的酚类化合物

建立了同时测定中国蜂胶水提物中23种酚类化合物的反相高效液相色谱(RP-HPLC)分析方法.采用ZORBAX Eclipse XDB C_(18)色谱柱(150 mm×4.6 mm×5 μm);流动相:甲醇-0.1%甲酸,梯度洗脱,流速1.0 mL/min,检测波长为256和280 nm,进样量20 μL,柱温35 ℃.各对照品质量浓度与色谱峰面积线性关系良好,具有较好的精确度和重现性,标准加入回收率在93.29%～106.61%之间.采用此法,从河北蜂胶中检测出18种对照品,其中表儿茶素含量最高35.50 mg/g WEP,其次是3,4-二甲氨肉桂酸15.41 mg/g WEP.而云南蜂胶中检测到9种对照品,表儿茶素含量最高11.23 mg/g WEP,其次是白杨素3.61 mg/g WEP,两地蜂胶WEP的HPLC图相似度分别为0.099(256 nm) 和0.194(280 nm),化学成分差异明显.     

高效液相色谱法同时测定纺织品中10种酚类化合物

建立了高效液相色谱法同时测定纺织品中五氯苯酚、2,3,4,5-四氯苯酚、2,3,4,6-四氯苯酚、2,3,5,6-四氯苯酚、2,4,5-三氯苯酚、2,4,6-三氯苯酚、邻苯基苯酚、间羟基联苯、2-萘酚、对硝基苯酚10种酚类化合物的检测方法。纺织品中的酚类化合物经甲醇超声提取、浓缩后,以ZORBAX SB-C18柱(4.6 mm×150 mm,5μm)为分析柱,乙腈和0.01 mol/L磷酸溶液为流动相梯度洗脱,采用二极管阵列检测器,在220 nm和310 nm波长下进行高效液相色谱检测,紫外光谱库确证,外标法定量。10种酚类化合物在0.3～37 mg/L浓度范围内与其峰面积呈良好的线性关系,相关系数为0.999 1～0.999 5;以不低于3倍的信噪比计算10种酚类化合物的检出限(LOD)为0.003 0～0.041 1 mg/kg;定量下限(LOQ,S/N≥10)为0.010 0～0.1370 mg/kg。棉、麻、毛3种纺织品基质在3个不同加标水平的回收率为81%～105%,相对标准偏差(RSDs)为1.7%～8.5%。该方法能同时完成10种酚类化合物的确证和分析,可用于纺织品中酚类化合物残留的检测分析。     

HPLC法同时测定松果菊属中4种酚类化合物

松果菊属(Echinacea Moenck.)是原产于美洲的一类菊科野生花卉,也称“紫锥菊”。该属植物共有8种及数个变种,均为多年生草本,其中已开发为药品者主要为淡紫松果菊(E.palli-a)、狭叶松果菊(E.angustifolia)及紫花松果菊(E.purpurea)[1]。松果菊属植物主要用于促进机体的免疫功能     

高效液相色谱法分析矿泉水中酚类化合物

用带荧光检测器的高效液相色谱法同时测定了矿泉水中的苯酚、甲酚、双酚Ａ、双酚Ｆ、４－叔丁酚、双酚Ａ二环氧甘油醚和双酚Ｆ二环氧甘油醚等,水样经液－固萃取浓缩后再进行分析,检测限可达０．１～０．２μｇ／Ｌ。重复测定的标准偏差为１．１２％～１３．２１％,水样测定的回收率为８１％～１０５％。     

固相萃取-反相HPLC分析色酒中有机酸

以高效液相色谱法对三种有色酒中的七种有机酸进行了分析。采用C18预处理柱进行样品前处理,固定相为μBondapak C18柱,流动相为 pH 2.9的5g·L-1磷酸氢二铵溶液,流速为1m1·min-1,检测波长为214nm,方法回收率为96％～113%,检出限为20～125ng。     

高效液相色谱-串联质谱法同时测定空气中10种酚类化合物的含量

提出了高效液相色谱-串联质谱法同时测定空气中苯酚、4-硝基酚、3-甲酚、2-氯酚、2,4-二甲酚、2,4-二氯酚、2,4,6-三氯酚、五氯酚、1-萘酚、2-萘酚等10种酚类化合物含量的方法。用XAD-7采样管采样,用甲醇洗脱;收集2.0 mL洗脱液,分取0.5 mL,再用水定容至1.0 mL,过0.22μm滤膜。以Kinetex C₁₈色谱柱为固定相,以不同体积比的甲醇-水的混合溶液为流动相进行梯度洗脱。分离后的酚类化合物经大气压化学电离源电离,多反应监测模式检测,外标法定量。结果表明：10种酚类化合物标准曲线的线性范围均为10～1 000μg·L^-1,检出限(3.143s)为0.2～1.7μg·m^-3;对空白样品进行3个浓度水平的加标回收试验,回收率为69.3%～102%,测定值的相对标准偏差(n=6)为1.1%～9.6%;方法用于10个实际空气样品分析,其中有3个样品检出苯酚,质量浓度为23.3～40.2μg·m^-3。     

Analysis of calcium blocker drugs in plasma,HRGC and HPLC analytical conditions for pharmacokinetic studies

Calcium blocker drugs are of increasing therapeutic relevance. Verapamil, nifedipine, diltiazem, and flunarizine are the most widely applied drugs of this type. New dihydropyridines (felodipine, nitrendipine) and related agents are presently undergoing intense investigation. HRGC and HPLC were used to determine eight of these drugs in spiked plasma samples. Both methods allow separation of most of the compounds in a single run and are specific, sensitive, and reproducible both for therapeutic monitoring and for pharmacokinetic studies in man and animals.     

A Stability Indicating HPLC Assay for Prednisolone Sodium Phosphate in Implantable Infusion Pumps

Abstract

A stability indicting assay for prednisolone sodium phosphate (PSP) in solutions for implantable infusion pumps was developed. PSP and its major breakdown product, prednisolone, were separated from formulation excipients by reverse phase chromatography on a phenyl-bonded phase column using an acetonitrile-phosphate buffer mobile phase. Detection was by ultraviolet absorbance at 243 mm. Recovery from a synthetic formulation was 101.0 ± 0.4% (n=6). The method was used to monitor the stability of PSP solutions in implantable infusion pumps maintained at 37°C over a 21 day period.     

Separation and Direct Chemical Determination of Nitrosamines by High Performance Liquid Chromatography (HPLC)

Abstract

Volatile and non-volatile nitrosamines are determined at subparts per million levels in a continuous, inexpensive, low-temperature procedure when samples are compatible with the aqueous-alcoholic solvents. Individual nitrosamines are resolved by gradient elution on appropriate HPLC columns, converted to nitrite ion by ultra-violet light, combined with modified Griess reagent and the red-colored product measured at 540 nanometers. Inorganic nitrite may be determined and two, organic compounds are known to interfere. The detection level for N-nitrosodimethyl amine is 0.1 parts per million.     

Separation and Detection of Arsenic and Selenium Species in Environmental Samples by HPLC-ICP-MS

A method is presented for arsenic speciation analysis of an oyster sample using ion chromatography coupled with an inductively coupled plasma mass spectrometry (ICP-MS) instrument. A strong anion exchange resin was employed with a step gradient elution of 0.1 mM/0.1 M K 2 SO 4 at pH 10.2. Arsenobetaine and dimethylarsinic acid were determined following extraction based on trypsin enzymolysis with 95-100% extraction efficiency. Limits of detection in the range 0.1-0.3 mg kg m 1 of arsenic were obtained for organic arsenic species. No inorganic arsenic was detected. Validation was performed using TORT-2 as a certified reference material. Although high performance liquid chromatography (HPLC) coupled to ICP-MS is an effective method for speciation analysis it is not always necessary to obtain such a detailed picture. A simple liquid chromatographic separation technique based upon mini-column technology is presented. It was developed to obtain a fast, efficient and reliable separation of inorganic from organic, i.e. assumed toxic from non-toxic, arsenic and selenium species suitable for use as an initial screening method for environmental analysis. Two types of strong anion exchange resin were tested. Excellent separation was obtained for both min-column resins and analysis times were within 7 min. Limits of detection obtained for inorganic arsenic, organic arsenic, selenomethionine, Se IV and Se VI were 1.6, 1.8, 66, 32 and 22 µg kg m 1 , respectively.     

生物技术培养银杏发根中的黄酮分析研究

本文研究了银杏发根中黄酮含量的高效液相色谱（ＨＰＬＣ）分析方法,改进了样品预处理过程,实行提取、水解同步进行,并与天然银杏树叶中的黄酮进行了对照,分析结果表明,采用生物技术培养的银杏发根中确实含有银杏黄酮。     

Electronic Tongue Applied to Phenolic Compounds Analysis

Abstract

A new voltammetric electronic tongue has been developed for the simultaneous determination of p-aminophenol, p-chlorophenol, and p-chloro-m-methylphenol. The three analytes are high environmental pollutants. Three epoxy-graphite composite electrodes have been used as detectors, with two of them being modified by the addition of metal catalysts in their composition. Simple fixed potential voltammetry has been used in order to simplify measurements. Artificial neural networks were used as chemometric tools for learning and prediction of the system. Good correlations in both modeling and predicting capacities have been obtained for the range of 1 to 28 µM of the three phenolic compounds.     

HPLC法测定醋酸纤维素膜材料界面参数

以醋酸纤维素(CA-398)膜材料为填料,用HPLC法测定无机溶质(如氯化钠,硫酸镁)和多官能团的有机溶质(如糖等)的保留体积V_R’,平衡分配系数K_A’。由HPLC实验数据来确定聚合物膜材料界面参数。     

A Simplified Method for Determination of Nifedipine in Human Plasma by High Performance Liquid Chromatography

Abstract

A simplified high performance liquid chromatographic method was developed to determine the levels of nifedipine in human plasma. Nifedipine and the internal standard, 11-ketoprogesterone, are extracted from alkalinized plasma into organic solvent. The organic solvent is then evaporated to total dryness and the analytes are reconstituted with mobile phase and chromatographed. The limit of quantitation is 10 ng/ml using a 1.0 ml plasma sample.     

Micromethod for Determination of Thiopental in Biological Fluids by High Performance Liquid Chromatography. Application to Therapeutic Follow-Up and Pharmacokinetic Study

Abstract

Thiopental is an ultra-short acting barbiturate, used either to induce anesthesia, or to manage intracranial hypertension associated with head injuries. A high performance liquid chromatography method vas proposed for the rapid and easy determination of thiopental in biological fluids. After precipitation of proteins with acetonitrile the chromatographic separation vas performed onto a reversed-phase column with an acetonitrile-perchlorate buffer mixture as mobile phase. Compounds were analysed at 300nm and the detection limit vas about 0.1 mg/1. The analytical procedure vas applied to the therapeutic follow-up in patients (8 childrens. 4 adults) treated with long-term infusion of thiopental after head injury, and to a pharmacokinetic study in patients receiving a single 1Y bolus of thiopental to induce anesthesia.