双烯醇酮醋酸酯荧光性质及应用研究

研究了双烯醇酮醋酸酯的荧光性质,考察了荧光性质的影响因素,提出了测定其荧光强度的荧光光谱分析法。该方法灵敏度高,检出限为5 3×10-8mol·L-1。荧光强度与双烯醇酮醋酸酯的浓度在1 3×10-7～1 0×10-5mol·L-1范围内呈良好的线性关系,相关系数为0 9996。     

银纳米粒子-锌(Ⅱ)协同双催化动力学荧光法测定电镀工业废水中痕量锌

在含有十六烷基三甲基溴化胺(CTMAB)的磷酸盐(PBS)缓冲溶液中,Zn²⁺对高碘酸钠氧化荧光桃红的反应具有显著的催化效应,催化的结果是导致其荧光强度显著减弱。据此建立了基于Zn²⁺和银纳米粒子协同双催化效应动力学荧光法测定痕量Zn²⁺的新方法。实验结果表明pH 7.8的磷酸盐缓冲溶液中,当荧光桃红、NaIO₄、银纳米粒子、CTMAB溶液浓度分别为2.0×10^-6 mol/L,5.0×10^-3 g/L,5.0×10^-6 mol/L ,1.5×10^-3 g/L时,Zn²⁺的浓度在5×10^-8 ~ 100×10^-8 g/L范围内与体系的荧光强度改变值呈良好的线性关系,检出限为1.88×10^-8 g/L。应用于电镀工业废水中Zn²⁺的检测,测定值与双硫腙光度法基本一致,相对标准偏差(RSD,n=6)≤2.5%。     

阻抑动力学荧光法测定痕量钴

在氢氧化钠碱性介质中,痕量钴(Ⅱ)对过氧化氢氧化二氯荧光素的反应具有强烈的抑制作用。过氧化氢在氧化二氯荧光素时,使反应体系的荧光强度减弱;当加入痕量钴(Ⅱ)时,体系的荧光强度增强,钴(Ⅱ)对氧化反应具有抑制作用。反应体系的激发波长和发射波长分别为492和5 15nm ,测定钴(Ⅱ)的线性范围为0 .2 4～3 .2 μg·L- 1 ,检出限为0 .12 μg·L- 1 。该法用于茶叶和人发样品中痕量钴(Ⅱ)的测定,结果满意。     

茶饮料中糖精钠的测定

建立了茶饮料中糖精钠的荧光分光光度测定方法。样品前处理采用盐酸酸化,加入氯化钠,乙醚萃取后再用2 g/L碳酸钠溶液洗涤乙醚萃取层,加热除去乙醚定容后用荧光光度计测定。测试条件为：激发波长265 nm,发射波长475 nm。方法检测限为2 mg/kg,线性范围在2～60 mg/kg之间,变异系数为1.97%,回收率96.8%。     

Study of OH Radicals in Human Serum Blood of Healthy Individuals and Those with Pathological Schizophrenia

The human body is constantly under attack from free radicals that occur as part of normal cell metabolism, and by exposure to environmental factors such as UV light, cigarette smoke, environmental pollutants and gamma radiation. The resulting “Reactive Oxygen Species” (ROS) circulate freely in the body with access to all organs and tissues, which can have serious repercussions throughout the body. The body possesses a number of mechanisms both to control the production of ROS and to cope with free radicals in order to limit or repair damage to tissues. Overproduction of ROS or insufficient defense mechanisms leads to a dangerous disbalance in the organism. Thereby several pathomechanisms implicated in over 100 human diseases, e.g., cardiovascular disease, cancer, diabetes mellitus, physiological disease, aging, etc., can be induced. Thus, a detailed investigation on the quantity of oxygen radicals, such as hydroxyl radicals (OH^•) in human serum blood, and its possible correlation with antioxidant therapy effects, is highly topical. The subject of this study was the influence of schizophrenia on the amount of OH^• in human serum blood. The radicals were detected by fluorimetry, using terephthalic acid as a chemical trap. For all experiments the serum blood of healthy people was used as a control group.     

反相胶束增稳室温荧光法测定痕量中药有效成分盐酸小檗碱的研究——兔血浆中痕量盐酸小檗碱的测定

研究了双［２－乙基己基］－磺酸基琥珀酸／环己烷／水（ＡＯＴ／Ｃ６Ｈ１２／Ｈ２Ｏ）反相胶束介质中中药有效成分盐酸小檗碱的荧光性质．并将该法应用于兔血浆中痕量盐酸小檗碱的测定，绘制了药时曲线．该法的线性范围（ｇ／ｍＬ）为：６．０×１０－８～６．０×１０－５，检出限（ｇ／ｍＬ）为：７．２×１０－８，相对标准偏差（％）为：１．１     

荧光分析法在药学研究中的应用进展

本文综述了常规荧光分析法及新型荧光分析技术在药学研究中的应用,并探讨了荧光分析法在天然药物化学研究中的意义,为中药成分研究提供参考.     

Differential Scanning Fluorimetry for Monitoring RNA Stability

Cellular RNA function is closely linked to RNA structure. It is therefore imperative to develop methods that report on structural stability of RNA and how it is modulated by binding of ions, other osmolytes, and RNA‐binding ligands. Here, we present a novel method to analyze the stability of virtually any structured RNA in a highly parallel fashion. This method can easily determine the influence of various additives on RNA stability, and even characterize ligand‐induced stabilization of riboswitch RNA. Current approaches to assess RNA stability include thermal melting profiles (absorption or circular dichroism) and differential scanning calorimetry. These techniques, however, require a substantial amount of material and cannot be significantly parallelized. Current fluorescence spectroscopic methods rely on intercalating dyes, which alter the stability of RNA. We employ the commercial fluorescent dye RiboGreen, which discriminates between single‐stranded (or unstructured regions) and double‐stranded RNA. Binding leads to an increase in fluorescence quantum yield, and thus reports structural changes by a change in fluorescence intensity.     

Evaluation of Light Scattering and Autofluorescent Properties of Brewer's Worts for Flow Cytometric Analysis of Yeast Viability

Flow cytometric methods for determining yeast viability are currently available. For effective analysis of yeast in breweries it is important that the light scattering properties of the sample medium (wort) do not interfere with that of target yeast cells. For this reason, a number of wort samples were analysed for their light scattering and autofluorescent properties, as well as their ability to bind the yeast viability dye, oxonol. Worts were found to produce light scattering that was sufficiently different from yeast, such that the two were clearly distinguishable by flow cytometry. Although oxonol bound to wort particles, computer software techniques allowed determination of yeast viability in worts.