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以D-色氨酸为保护剂和还原剂, 采用水热法快速制备了具有强荧光的金纳米簇(D-Trp@AuNCs); 以其作为荧光探针, 建立了基于荧光猝灭的选择性高灵敏检测Fe3+的传感方法. 利用透射电子显微镜(TEM)、 紫外-可见光谱(UV-Vis)和红外光谱(IR)等手段对制备的金纳米簇进行了表征, 并利用荧光光谱研究了D-Trp@AuNCs的荧光性能. 结果表明, D-Trp@AuNCs具有较好的生物相容性, 其最大激发波长为370 nm, 最大发射波长为460 nm; 向金纳米簇溶液中加入Fe3+后, D-Trp@AuNCs的荧光发生明显猝灭, 其猝灭程度与Fe3+的浓度在0.3~500.0 μmol/L范围内呈现良好的线性关系, 检出限为33.1 nmol/L(S/N=3). 将该荧光探针用于实际水样中Fe3+的检测, 回收率为86.6%~106.5%. 相似文献
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生态纺织品中铬(Ⅵ)含量有严格的限制.本实验利用海藻酸钠一步法成功合成了纳米金溶胶,并对其荧光特性进行了研究.结果表明,海藻酸钠-纳米金复合物(AuNPs-SA)在激发波长λex=330 nm处表现出最强荧光特性,在该激发波长下,最大发射波长λem=415 nm.铬(Ⅵ)对海藻酸钠-纳米金复合物的荧光有猝灭效应,纳米金荧光强度随铬(Ⅵ)浓度的增加而减弱,利用其荧光猝灭特性建立了铬(Ⅵ)定量分析方法.调节AuNPs-SA溶液至pH 7.0,加入Cr(Ⅵ),反应40 min后,测定荧光强度变化.铬(Ⅵ)浓度在1.0×10-8~9.0×10-8 moL/L范围内与F/F0有较好的线性关系(R=0.9919),方法的检出限(S/N=3)为5.0×10-9 mol/L.本方法用于纺织品中苎麻与涤纶的痕量铬(Ⅵ)的检测,所得结果与国家标准方法(GB/T 17593.3-2006)没有显著性差异. 相似文献
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《分析科学学报》2021,37(5)
以CuCl_2为原料,聚乙烯吡咯烷酮(PVP)为模板,2-巯基苯并噻唑(MBT)为稳定剂,葡萄糖为还原剂,采用化学还原法制备一种新的铜纳米簇(Cu NCs)荧光探针,并用于快速检测林可霉素。该Cu NCs在激发波长为335 nm下,于发射波长为580 mm处发出黄绿色荧光,林可霉素通过与MBT反应,破坏了其对Cu NCs的保护作用使其荧光猝灭,且猝灭程度与林可霉素的含量成正比,据此建立了一种快速检测林可霉素的新方法。测定林可霉素最佳条件为:pH=5.0的HAc缓冲溶液,温度30℃下反应40 min。林可霉素的浓度分别在4.0×10~(-8)~8.0×10~(-7) mol/L和8.0×10~(-7)~2.0×10~(-5) mol/L范围内与荧光猝灭程度(ΔF)呈良好线性关系,方法的检出限为1.01×10~(-8) mol/L。采用本法和国家标准方法测定同一样品,t检验法结果P0.05,说明两种方法没有显著性差异。此纳米探针制作简单,原料便宜,用于盐酸林可霉素针剂和牛奶中林可霉素的检测,回收率为99.6%~103.4%。 相似文献
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氯金酸-罗丹明S缔合纳米微粒体系的共振散射增强与荧光猝灭研究 总被引:8,自引:0,他引:8
在0.2mol/L HCl介质中,罗丹明S(RDS)分别在520nm和550nm处有一个吸收峰和荧光峰。当有Au(Ⅲ)存在时,Au(Ⅲ)与Cl^-形成AuCl4^-,AuCl^-与RDS^ 借助于静电引力形成疏水性的AuCl4-RDS缔合物分子。AuCl4-RDS分子间存在较强的分子间作用力和疏水作用力而生成(AuCl4-RDS)。缔合纳米微粒,粒径为45nm。在360nm产生瑞利散射峰,在600nm产生共振散射峰。由于纳米微粒形成后,只有裹露在(AuCl4-RDS)n纳米微粒界面的RDS荧光分子才能吸收激发光子跃迁到激发态,进而返回基态产生荧光。而体相的RDS荧光分子无法与激发光作用产生荧光,即受激RDS分子数大为降低,故550nm荧光峰和520nm吸收峰的降低。当缔合纳米微粒体系加入乙醇后,体系的红紫色和共振散射峰消失,吸收峰和荧光峰恢复,由于乙醇致使(AuCl4-RDS)。纳米微粒分解为AuCl4-RDS分子。结果表明:红紫色(AuCl4-RDS)n纳米粒子的形成是其共振散射增强、荧光猝灭和产生共振散射峰的根本原因。 相似文献
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近年来,贵金属纳米材料由于其具有独特的光学性质、稳定性、生物相容性和自身的结构特性等优点,被广泛用于重金属检测领域。总结了近年来金纳米粒子在重金属离子检测方面的研究现状,最后对贵金属纳米材料在重金属离子检测中的发展前景进行了展望。 相似文献
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近年来,贵金属纳米材料由于其具有独特的光学性质、稳定性、生物相容性和自身的结构特性等优点,被广泛用于重金属检测领域。总结了近年来金纳米粒子在重金属离子检测方面的研究现状,最后对贵金属纳米材料在重金属离子检测中的发展前景进行了展望。 相似文献
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ATP是机体代谢过程中不可或缺的能量物质,参与机体的各项重要的生理生化活动,在各方面起着至关重要的作用。因此,对ATP的快速精准检测具有重要的临床意义。纳米金(AuNPs)因优良的光学特性、催化活性、生物相容性等特点,被广泛应用于构建ATP检测体系。本文综述了目前AuNPs应用于ATP检测的研究进展,如比色检测、荧光分析、电化学检测、电化学发光检测、化学发光检测以及表面增强拉曼散射等,比较了各种检测方法的优点与不足,并对AuNPs在ATP检测应用中面临的挑战和机遇做了展望。 相似文献
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《Analytical letters》2012,45(15):2236-2245
The fluorescence quenching technique was applied to study the interactions between lysozyme and Gold nanoparticles (GNPs). GNPs were synthesized by microwave assisted heating under reflux, using trisodium citrate as the reducing agent. The UV-visible spectra and TEM image were used to characterize the GNPs. The GNPs had a maximum absorption peak at 520 nm, with an average diameter of 13.3 nm. The fluorescence quenching mechanism was studied by Stern-Volmer equation. It was proved that the fluorescence quenching of lysozyme by GNPs was mainly a result of the formation of a lysozyme-GNP complex. Experimental results indicated that the combination reactions of GNPs and lysozyme were static quenching processes. It can be expected that the fluorescence quenching technique could provide a promising tool to study the interactions of GNPs and proteins. The binding constants, the number of binding sites at different temperatures and corresponding thermodynamic parameters ΔG, ΔH, and ΔS were also calculated. 相似文献
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Xiao-Ming MA Mi SUN Yue LIN Yin-Jin LIU Fang LUO Long-Hua GUO Bin QIU Zhen-Yu LIN Guo-Nan CHEN 《分析化学》2018,46(1):1-10
Visual detection method is a means of quantitative analysis by the naked eye through the comparison of color intensity or type of change. Owing to its simplicity, low-cost, rapid operation, and equipment-free, visual detection was widely used in the detection of numerous targets. Gold nanomaterials were widely used in the construction of visual biosensors due to its unique optical properties when compared to other nanomaterials. The local surface plasmon resonance absorption peak would change with the variety in the distance or the morphology. Herein, this paper reviewed the application of gold nanomaterials in the construction of visual biosensors for the detection of target molecules. Meanwhile, we pointed out the main problems of gold nanoparticles based colorimetric methods in the determination of actual samples. The forecast of gold nanoparticles based biosensor was also provided at the end of this article. 相似文献
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以聚甲基丙烯酸单层保护的金纳米粒子(GNPs)作为传感器, 实现了水溶液中Pb2+的选择性循环检测.先采用柠檬酸钠还原法获得尺寸均匀的GNPs, 再通过具有硫醇端基的聚甲基丙烯酸与金的强耦合作用, 获得了聚甲基丙烯酸单层保护的金纳米粒子(PMAA-@-GNPs).动态光散射、紫外-可见吸收光谱及透射电子显微镜表征证实了其单层结构.在Pb2+的诱导下, PMAA-@-GNPs溶液颜色从酒红色变为紫色并可肉眼识别.透射电子显微镜结果证实, 这种变化是由于Pb2+交联羧基使聚合物发生收缩, 并诱导GNPs的聚集所致.对比Pb2+与Hg2+, Mg2+, Cu2+, Zn2+, Na+, Ni2+, Fe3+, Cd2+, K+和Fe2+溶液颜色的变化, 证实此体系具有一定的选择性.用EDTA可夺取交联的Pb2+, 使PMAA-@-GNPs 的吸收峰恢复并可用于循环检测Pb2+. 相似文献
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纳米金是金的微小颗粒,在水溶液中以胶体金的形态存在。胶体金的颜色会随着其粒径及表面修饰差异而发生变化,这种颜色变化可通过肉眼观察;同时,这种改变会产生强烈的光散射或光吸收信号。基于这种信号而建立的纳米金比色检测法,已被广泛用于生物分子(如核酸、蛋白质、多糖甚至是细胞)的检测。DNA功能化纳米生物传感器是利用核酸碱基配对原则进行识别,能实现特定基因片段的持续、快速、灵敏和选择性检测。本文结合最近十年的研究现状,主要论述了DNA功能化纳米金用于比色检测法的原理及用于核酸、蛋白质和部分生物小分子的检测,并评述了其中的挑战和前景。 相似文献
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We report our findings that natural flavonoids such as quercetin, daizeol and puerarin can act as reductants for the enlargement
of gold nanoparticles (Au-NPs). Consequently, the UV–vis spectra of a solution containing Au-NPs will be gradually changed,
and the molecules of the natural herbs can be detected by making use of changes in the UV–visible spectra. Furthermore, we
have prepared a self-assembled monolayer modified electrode by modifying cysteamine on a gold substrate electrode, which is
further modified by some Au-NP seeds. When the modified electrode is immersed in a solution containing flavonoids and tetrachloroauric
acid as a gold source for the growth of the Au-NP seeds, with the increase of the concentration of flavonoids, the Au-NP seeds
on the surface of the modified electrode can be enlarged to varying degrees. As a result, the peak currents in the corresponding
cyclic voltammograms are inversely decreased, and simultaneously the peak separation is increased. Therefore, an electrochemical
method to detect flavonoids is also proposed. Compared with the optical detection method, the electrochemical method has an
extraordinarily lower detection limit and a significantly extended detection range. Moreover, the optical and electrochemical
experimental results can be also used to assay and compare the relative antioxidant activities of the flavonoids.
Figure Enlargement of Au nanoparticles by flavonoids at cysteamine modified electrode 相似文献