Development of a method for the quantification of the molar gold concentration in tumour cells exposed to gold-containing drugs

The knowledge of the cellular molar concentration of a drug is an extremely important parameter for the discussion and interpretation of its efficacy and bioavailability. Concerning metal complexes, electrothermal atomic absorption spectroscopy (ETAAS) offers a valuable analytical tool. However, matrix effects often hamper proper quantification of the metal concentration in biological tissues. This paper describes the development of an ETAAS method for the quantification of the molar gold concentration in HT-29 colon carcinoma cells. ETAAS analytical conditions were optimised and a factor was developed which allows the calculation of the molar cellular gold concentration from the measured gold per cellular biomass value. The method was used to quantify the gold content in HT-29 cells after exposure to the gold drug auranofin. Results indicated a strong cellular uptake of auranofin (compared to other metal anticancer drugs), which significantly correlated with the antiproliferative effects triggered by this agent.     

火焰原子吸收法测定磷矿中铬的不确定度探讨

研究了火焰原子吸收法测定磷矿中铬含量引起的不确定度评定。首先介绍了实验用到的仪器及实验试剂的制备,接着对实验过程中的不确定度来源做了深入研究和分析,最后计算了合成不确定度。     

增感效应乳浊液进样FAAS法测定面漆中的镉、铅、总铬

探讨了乳浊液进样FAAS(火焰原子吸收光谱)法测定面漆中镉、铅、总铬含量的分析方法。用乳浊液进样技术处理样品,即将样品溶解于丙酮,加入1:1无水乙醇 Triton X-100溶液制成乳浊液,直接喷入空气-乙炔火焰测定。通过在与样品乳浊液等体积的空白溶液中加入适量的甘油,可配成与试液粘度一致的参比溶液。以异丙醇为增敏试剂,用工作曲线法测定,此法准确、快速、方便,测定结果与传统湿法一致,t检验表明:两种样品前处理方法无显著性差异,相对误差小于5.0%。     

原子吸收测定油漆、涂料中铅镉铬的干扰消除研究

通过对重金属铅、镉、铬石墨炉原子吸收分析中存在的光谱干扰和化学干扰进行研究分析.通过优化实验条件以及选择合适的基体改进剂,有效消除了干扰,提高了分析准确度及检测灵敏度.     

火焰原子吸收法测定磷矿石、磷酸中铬

研究了火焰原子吸收光谱法测定磷矿石、磷酸中铬的方法,磷矿石试样经消解液溶解,磷矿石试液、磷酸试液分别以盐酸和硝酸为介质,加入一定量KCl溶液,于波长357.9nm处测量试样吸光值,由标准加入曲线得出铬含量。本方法磷矿石与磷酸样品的加标回收率分别为96.2~104.6%和97.4~105.9%,磷矿石与磷酸样品的相对标准偏差分别为1.97%~3.16%和3.86%~5.28%,精密度和准确度较高。     

火焰原子吸收分光光度法测定总铬的研究

研究了火焰原子吸收分光光度法直接测定水和废水中的总铬,确定了最佳的分析条件,验证了方法的准确度和精密度。     

漆膜厚度等因素对测定涂料中可溶性铅、铬含量的影响

用火焰原子吸收法测定涂料中可溶性铅、铬含量,在室温、盐酸酸度、搅拌速度等条件恒定的情况下,考察了漆膜厚度、粉碎颗粒大小对实验结果的影响。试验表明测试结果受漆膜厚度、粉碎颗粒大小的影响很大。     

三价铬电镀硬铬及镀层性能的研究

在甲酸盐体系中制备厚度为50μm硬铬镀层,并对镀层的沉积速率、硬度、粗糙度及耐磨耐蚀性能进行了考察.结果表明:在电镀初期镀层的厚度和沉积时间成正比,而且镀层外观质量良好,当电镀50min后镀层质量下降,镀层粗糙度随着镀层厚度的增加而增大;未经热处理,镀层的硬度及耐磨性能和六价铬镀层相差不大,经过600℃热处理后镀层的硬度增大,而耐磨性能反而减小;三价铬镀层比六价铬镀层更不容易被腐蚀,但一旦被腐蚀,前者的被腐蚀速率比后者的要大.     

我国铅铬系颜料工业现状和应用领域评价

分析了我国铅铬系颜料工业生产经营现状,对铅铬系颜料工业的应用领域和发展前景进行了评价。     

水中总铬测定方法的对比分析

分别用高锰酸钾氧化—二苯碳酰二肼分光光度法和直接吸入火焰原子吸收法测定国家标准样品及不同类型水中的总铬,结果表明,用直接吸入火焰原子吸收法和高锰酸钾氧化—二苯碳酰二肼分光光度法测定标准样品,结果均在真值允许范围内。两种方法测定不同类型水中的总铬结果无明显差异,相对偏差均小于10%,回收率为86～119%。     

Synthesis,Evaluation, and Gelation Mechanism of Organic Chromium

Since the launching of tertiary oil recovery, the performance requirements of polymer solution increasing, the polymer solution is more difficult to meet the needs of the scene. It could solve poor profile control, salt‐tolerant, and poor performance that crosslinking agent was added to polymer solution. Therefore, chromium acetate crosslinker was synthesized, and the synthesis conditions were optimized, and the performance of crosslinking agent was evaluated. Through optimization, the optimum conditions of chromium acetate synthesis was: reaction time 10 h, reaction temperature 80°C, the molar ratio of acetic acid and potassium dichromate than or equal to 24 : 1. Performance evaluation showed that adding crosslinking agent could significantly increase the viscosity of the polymer solution, could significantly improve the resistance coefficient and residual resistance of the polymer solution, and could play a good role profile flooding. Studies showed that when salinity and ion content changed, the crosslinking mechanism of changed. Through the study of molecule coil size at room temperature, the molecule coil size would slightly decline after 1 h, suggesting that crosslinking mechanism was intramolecular crosslinking reaction occurs at first, and then intermolecular crosslinking reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

火焰原子吸收分光光度法测定钛白粉中的微量铅

建立用火焰原子吸收分光光度法测定钛白粉中微量铅的新方法,确立了仪器的工作条件,其线性关系良好。该方法简便、快速、准确、效果令人满意。     

氯化铬对热镀锌板三价铬钝化膜的影响

采用中性盐雾试验、醋酸铅点滴试验以及电化学极化和阻抗测试方法,研究了不同浓度的氯化铬对热镀锌板三价铬钝化膜耐蚀性能的影响;采用金相显微镜观察了钝化膜极化后的腐蚀形貌。研究表明,钝化膜中以Cr Cl3·6H2O为主要成膜物,当浓度在0.6~1.0 mol/L时,钝化膜耐中性盐雾试验和醋酸铅点滴时间最长,在3.5%Na Cl溶液中腐蚀电流最小、低频阻抗值最大,并分析了氯化铬浓度对钝化膜耐蚀性的影响。     

微波消解-火焰原子吸收光谱法测定玻璃制品中铅、镉含量

文章应用微波消解-原子吸收光谱法同时测定玻璃制品中铅、镉含量。采用8 mL硝酸 1 mL过氧化氢 2 mL氢氟酸的微波消解体系,消解液无需赶酸,定容后直接用原子吸收光谱仪测定。实验发现,该方法消解效率高、重现性好、可操作性强,准确快速。该方法铅回收率为93.3%;镉回收率为95.5%。方法检出限:铅:0.01 mg/L,镉:0.001 mg/L。     

成都市售皮蛋中重金属铅、锌含量的分析

以成都市部分市场的皮蛋为样品,以铅、锌含量为检测对象。采用石墨炉原子吸收光谱法测定铅的含量,火焰原子吸收光谱法测定锌的含量。实验结果表明,皮蛋中Pb含量为0.20~0.31μg/g,Zn含量为11.39~17.02μg/g。根据国家标准规定,传统工艺生产的皮蛋Pb含量最高标准为3.00μg/g,其他工艺生产的皮蛋Zn含量最高标准为20.00μg/g。实验结果与国家皮蛋中重金属含量标准相比,成都部分市场的皮蛋中的锌与铅的含量均在安全范围内。     

生物除铬的机理研究

本论文主要是研究厌氧微生物作为生物絮凝剂吸附六价铬的吸附特性及机理。污泥中的微生物以杆菌为主。污泥吸附沉降性良好。污泥在吸附时间40 min内,不会解析,吸附效果最好。在污泥吸附能力达到饱和时,加入营养经过一段时间后,其吸附能力会部分恢复。     

化学原子化器AAS测定生活污水中痕量砷和铅的研究

一般原子吸收法对成分复杂样品中痕量As、Pb元素测定较为困难。微型化学原子化器-原子吸收光谱法因其特殊的机理和结构,通过对介质酸度、NaBH4、载气流速等影响因素的优化,可直接测定生活污水中的As和Pb。相较于一般氢化发生器优点在于快速,成本低,干扰性小,不需要用HCl和NaBH4作载流,NaBH4的消耗可以节省90%以上。     

Motuporamine Derivatives as Antimicrobial Agents and Antibiotic Enhancers against Resistant Gram‐Negative Bacteria

Dihydromotuporamine C and its derivatives were evaluated for their in vitro antimicrobial activities and antibiotic enhancement properties against Gram‐negative bacteria and clinical isolates. The mechanism of action of one of these derivatives, MOTU‐N44, was investigated against Enterobacter aerogenes by using fluorescent dyes to evaluate outer‐membrane depolarization and permeabilization. Its efficiency correlated with inhibition of dye transport, thus suggesting that these molecules inhibit drug transporters by de‐energization of the efflux pump rather than by direct interaction of the molecule with the pump. This suggests that depowering the efflux pump provides another strategy to address antibiotic resistance.     

Cr2O3添加量对95铬刚玉瓷耐磨性能的影响

加入适量的Cr2O3可以改善95铬刚玉瓷的耐磨性.通过一系列的实验得知,当加入4%Cr2O3,常压下,1 583 ℃,保温2 h可以制得耐磨性能很好的铬刚玉瓷.这种提高95铬刚玉瓷耐磨性的方法非常实用.