高效液相色谱法同时测定多维元素片中9种水溶性维生素

采用更简便的流动相体系,建立了高效液相色谱法同时测定多维元素片中9种水溶性维生素的快速分析方法。以酸水解与离心的方法处理样品,用C8柱分离,流动相A为0.1%三氟乙酸的水溶液,B为甲醇,梯度洗脱,二极管阵列检测器(DAD)检测。28min内实现了9种水溶性维生素的同时分离测定。各维生素线性关系、精密度、回收率均良好。并使用美国国家标准技术研究院(NIST)的SRM3280多维元素片标准物质对方法进行了确认,运用此法测定了市售多维元素片中的水溶性维生素含量。该法可作为维生素片剂中水溶性维生素分离测定的质控方法。     

基于洗瓶的泡腾片探究实验

利用洗瓶为基本仪器完成对泡腾片中NaHCO3的含量的探究,用该方法还可以测定CO2的摩尔质量。     

碳棒电极示波极谱阳极溶出法测定多维元素片中微量铜和锌

采用碳棒电极示波极谱阳极溶出法在同一系统中，直接测定多维元素片中的微量铜和锌。在0.05mol.L^-1,KSCN-0.01mol.L^-1,HCl介质中，铜和锌的溶出峰电位分别为－0．23V（vs.SCE)和－0．90V。铜和锌分别在20－400μg.L^-1及50－800μg.L^-1范围内呈良好的线性关系，平均回收率为96％和98％，此法不用汞工作电极，无污染，具有较好的重复性和准确性。     

合金中痕量元素标准物质研制进展

通过对国内外高温合金、铝合金痕量元素标准物质的比较,评述了我国合金中痕量元素标准物质在种类、量值水平及不确定度等方面的进展。     

高效液相色谱法测定奥硝唑阴道泡腾片中奥硝唑的含量

提出了用高效液相色谱法测定奥硝唑阴道泡腾片中奥硝唑含量的方法.以KromasilC18色谱柱(4.6 mm×250 mm,5μm)为固定相,甲醇-水(30+70)溶液为流动相,在319 nm波长处用紫外分光检测器检测.奥硝唑的质量浓度在20.0～80.0 mg·L-1之间与其相应的峰面积值呈线性关系.应用此法测定奥硝唑阴道泡腾片中奥硝唑的含量,回收率在98.9%～100.1%之间,测定值的相对标准偏差(n=6)均小于0.9%.     

ICP-AES法测定鸡汤中多种矿物质元素

采用电感耦合等离子体发射光谱法(ICP - AES)对不同烹煮时间的鸡汤及加不同量冰乙酸烹煮的鸡汤中Ca、Mg、Fe、Cu、Zn等5种矿物质元素进行了分析研究.结果表明,不同烹煮时间的鸡汤中Ca、Mg、Fe、Cu、Zn溶出量有显著性差异(P＜0.01),Ca、Fe的溶出量随着时间的增加而增加;加冰乙酸烹煮的鸡汤中Ca、...     

多维液相柱色谱

多维液相柱色谱分离分析复杂样品越来越受到重视。本文介绍了国内外多维液相柱色谱的近期发展,详细讨论了二维液相色谱的实现,其中包括固定相、流动相的选择、温度变量的作用以及两维间切换的实现,并对多维液相柱色谱的应用现状进行了总结。     

问题引领下探究Vc泡腾片的课例实录与体会

利用Vc泡腾片与水反应创设情境,引发一系列学生想要探究的问题;教师引领学生共同分析问题,用实验的方法逐一揭示现象背后的本质。通过对核心问题“Vc泡腾片溶于水产生的气体是什么?为什么会产生二氧化碳气体?”的解决,学生在主动探究中重新认识了氧气、二氧化碳和酸的性质,思维能力和学习能力得到进一步提升,同时能感受到化学的魅力,感受到生活因化学而精彩。     

元素间的相互影响

综述了机体内元素间的相互影响,包括：锌、铁、铜、硒、钼、锰、铝与其它元素的相互影响或关系,以及宏量元素间、宏量元素与微量元素间的影响。     

糙米、胚芽米、精白米中多种矿质元素和B族维生素含量的比较研究

对产自黑龙江省绥化市的同一批粳稻分别进行加工制得糙米、胚芽米和精白米,经过干灰化法或微波消解处理后,采用电感耦合等离子体发射光谱法（ICP—OES）、原子吸收光谱法（AAS）和原子荧光光谱法（AFS）测定了其中Al、As、B、Ba、Ca、Cd、Co、cr、Cu、Fe、Hg、K、Mg、Mn、Mo、Na、Ni、P、Pb、Rb、S、Se和zn共23种矿质元素的含量,,并采用高效液相色谱法（HPLC）和荧光分光光度法测定了其中维生素B．,烟酸,烟酰胺,维生素B。和维生素B：的含量。另外,还研究了经水淘洗后这3种类型大米中矿质元素和B族维生素含量的损失情况。结果表明,矿质元素和B族维生素含量呈现糙米,胚芽米,精白米由高到低的基本特征,淘洗可使各种矿质元素和B族维生素产生不同程度的损失,其中精白米中维生素B．经水淘洗后已损失殆尽。3种类型大米中cd、Cu、Mo、Ni、S、Se、Zn等元素含量差异相对较小,并且淘洗对Mo、S元素含量几乎没有影响,而cd、cu元素含量经水淘洗后反而略有增加。     

Formulation of Risperidone as Self-Nanoemulsifying Drug Delivery System in Form of Effervescent Tablets

Risperidone is an atypical antipsychotic drug used to treat schizophrenia. This study aims to formulate risperidone as effervescent tablets to improve patient compliance. Different nanoemulsion combinations were loaded with risperidone to improve its poor water solubility then adsorbed on Aeroperl. The formula showing highest drug dissolution was formulated as effervescent tablets. Factorial design was applied for different tablet formulation variables and the prepared formulae were tested for different criteria in comparison with their corresponding formulae containing drug without nanoemulsion formulation. Statistical analysis was used to determine the most desirable tablet formula considering its Carr index, effervescence time, and drug release.     

反相高效液相色谱法同时测定食品和多维片中8种水溶性维生素

建立了以0．05mol/L KH2PO4-甲醇为流动相的梯度洗脱反相高效液相色谱同时测定水溶性维生素C,B1,B2,B6,B12,烟酸,烟酰胺和叶酸的分析方法,方法检出限为1．4－0．76ng,用该法测定了奶粉,玉米粉,饮料及复合维生素片中水溶性维生素,相对标准偏差为2．8％－8．8％,加标回收率为74．7％－112．5％。     

微乳毛细管电动色谱快速分析脂溶性维生素

建立了一种新的微乳体系,成功地应用于微乳毛细管电动色谱(MEEKC)快速分析脂溶性维生素VA、VD3和VE.本微乳液的组成为:1.2%(m/m)十二烷基硫酸钠(SDS)-21%(V/V)正丁醇-18%(V/V )乙腈-0.8%(m/m)正己烷-20 mmol/L H3BO3-Na2B4O7缓冲液( pH 8.4 ).该微乳体系中,助表面活性剂正丁醇和有机溶剂乙腈对脂溶性维生素的分离起到了重要的作用.当分离电压为25 kV,柱温为25 ℃时,VA、VD3和VE在13 min内达到基线分离.3种脂溶性维生素的迁移时间和峰面积的RSD(n= 5)<2.5%和4.5%;VA、VD3和VE分别在20～1000、5～1000和5～1000 mg/L范围内与峰面积呈线性关系;检出限(S/N=3)分别为12、 0.72和0.29 mg/L.本体系应用于市售VE胶囊的测定,结果与标示值相符.     

液相色谱法测定生物发酵液中水溶性维生素的研究

本文采用反相离子对色谱测定了生物发酵液中的七种水溶性维生素。提出了用自行装填的酸性氧化铝（０．１９～０．１５ｍｍ）前置柱，和５％乙酸洗脱样品的前处理方法；并就有关的色谱条件进行了选择。色谱柱为ＮｏｖａＰａｋＣ１８；流动相Ａ液为０．０５ｍｏｌ／Ｌ庚烷磺酸盐（ＰＩＣＢ７），冰乙酸调ｐＨ＝２．５；Ｂ液为甲醇＋三乙胺（１００＋０．５）；梯度洗脱；ＵＶ２５４ｎｍ、２９０ｎｍ、３６０ｎｍ同时测定。线性范围为０．１～１０μｇ，各种维生素的ＲＳＤ在１．２％～３．０％之间（ＶｉｔａｍｉｎＢ１２除外），回收率大于９０％。     

食用菌类中矿物质元素的研究

用火焰原子吸收分光光度法对广东清远笔架山的 1 7种食用菌、 2种木耳及灵芝中赤芝的 8种矿物质元素进行了测定。结果表明 ,食用菌类是优质食品 ,富含对人体有益的微量元素 ,有较高营养价值     

Extraction of Polyphenols and Vitamins Using Biodegradable ATPS Based on Ethyl Lactate

The growing human population, together with the inefficient use of natural resources, has been dramatically increasing the production of food waste, which poses serious economic, environmental, and social problems. Being so, it is necessary to increase the efficiency of food consumption so as to reduce its waste and to convert the remaining residues into societal benefits. Since this biowaste is rich in polyphenols and vitamins, it could become the feedstock for the production of important value-added compounds for the pharmaceutical (e.g., food supplements) and cosmetic (e.g., creams and shampoos) industries. In this work, partition studies of one polyphenol (epicatechin) and two B-complex vitamins (cyanocobalamin and nicotinic acid) were performed in biodegradable Aqueous Two-Phase Systems (ATPS) based on ethyl lactate and on organic salts (disodium tartrate, tripotassium citrate, and trisodium citrate) at 298.15 K and 0.1 MPa. The largest partition coefficient (K) and extraction efficiency (E) were obtained for vitamin B12 (K=78.56, E=97.5%) for the longest tie line TLL=77.66% in the ATPS {ethyl lactate (1) + tripotassium citrate (2) + water (3)}. All the extractions were obtained with low biomolecule mass losses in quantification (<5%) and after a thorough study of pH influence in the UV–Vis absorbance spectra.     

A Capillary Electrophoresis Detection Scheme for Water-soluble Vitamins Based on Luminol-BrO~- Chemiluminescence System

The detection of vitamins is of great interest due to the biological significance of these compounds. Several studies on the determination of vitamins have been performed using HPLC1,2, CE3,4. Chemiluminescence (CL) analysis shows excellent sensitivity, wide linear range and requires simple instrumentation for assay of vitamins5-7, but poor selectivity of CL greatly limits its application in analysis of complex systems. The research presented here describes some preliminary results on th…     

Nonionic Micellar Catalyzed Oxidation of Vitamins by Chloramine-T in HClO4 Medium: A Kinetic Study

The kinetics of oxidation of vitamin B₁ (thiamine hydrochloride) and vitamin B₆ (pyridoxine hydrochloride) by chloramine-T (CAT) in perchloric acid medium and in presence of a non ionic surfactant (Triton x-100) have been investigated. A catalytic effect of the nonionic micelle on the rate of oxidation has been observed and rate is found to be proportional to 7lcub;k′ + k″ [Triton x-100]}, where k′ and k″ are the rate constants in absence and presence of surfactant, respectively. The rate shows a first-order, a fractional order and a zero order dependence on [Chloramine-T]_o, [Vitamin]_o and [H⁺]₀, respectively in absence as well as in presence of surfactant. A mechanism involving association/binding between the oxidant and the surfactant micelle, which is supported by spectrophotometric evidence has been proposed. The binding parameters have also been evaluated using a pseudo-phase kinetic model.     

人体血清中3种脂溶性维生素的液相色谱-串联质谱分析方法研究

以人体血清中3种脂溶性维生素检测为例,探讨了一种针对人体内源性代谢物的分析方法。采用液相色谱-串联质谱(LC-MS/MS)对人体血清中维生素A、维生素D3和维生素E进行检测,分别通过混合人血清基质加入标准品及内标再扣除内源性物质本底的方法,以及与牛血清白蛋白(BSA)模拟基质加标的方法建立标准曲线进行定量分析。结果表明,采用混合人血清基质所建方法对维生素A、维生素D3和维生素E的检出限分别为4.2、0.8、67.2ng/mL,定量下限分别为13.7、2.6、221.9ng/mL。两种方法的线性相关系数均大于0.996;对于实际样品在低、高两个加标浓度下的回收率为90.7%~112%,相对标准偏差(RSD)为1.0%~4.5%,具有良好的准确性和重现性。对40组未知样本的检测结果表明,两种方法无统计学差异。因此,对于人体内源性代谢物采用混合人血清基质扣除本底的方法,可以实现标准品与待测样品基质匹配的准确分析,有利于临床相关疾病的便捷诊断。