共查询到20条相似文献,搜索用时 78 毫秒
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硫化镉纳米粒子的合成及荧光猝灭法测定Cu 2+的初步研究 总被引:1,自引:0,他引:1
以淀粉为包裹剂,硫脲为硫源,通过简单且“绿色”的途径,在水溶液中成功地合成了淀粉包裹的CdS纳米粒子。研究了纳米粒子的大小,不同的硫源、pH值、反应时间等条件因素对其吸收光谱和荧光光谱特性的影响,并以该纳米粒子作为荧光探针,初步探讨了痕量铜离子对其的荧光猝灭作用。结果表明:在最佳实验条件下,在2.0~50μg/L测定区间内铜离子呈现良好的线性(r=0.9986),证明该方法灵敏度高且简便易行,有望进一步开发其在生物样品微量元素分析中的应用。 相似文献
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半胱胺修饰的CdS纳米粒子荧光猝灭法测定锰离子 总被引:1,自引:1,他引:0
常温下在水溶液中制备了半胱胺修饰的CdS纳米溶胶,并用原子力和扫描电子显微镜、傅立叶变换红外、紫外-可见分光光度法、荧光分光光度法测试技术对其进行了表征. 以修饰的纳米粒子为荧光探针,建立了荧光猝灭定量检测锰离子的新方法. 考察了不同缓冲体系、缓冲液浓度及缓冲液pH值、反应时间、纳米粒子浓度等多种因素的影响. 在最佳实验条件下,测定锰离子的线性区间为0.053 40~77.62 mg/L,检出限为0.016 78 mg/L. 方法经济、简单、快速、灵敏度高、检出限比较低、检测范围宽. 相似文献
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荧光红-曙红Y能量转移及荧光猝灭法测定痕量铜(Ⅱ)的研究 总被引:9,自引:0,他引:9
在λex/λem=404.7/550nm,乳化剂OP存在下,荧光红-曙红Y能够发生有效能量转移,使曙红Y荧光强度大大提高;在pH6.5~7.6的KH2PO4-NaOH缓冲溶液中,Cu(Ⅱ)与曙红Y和邻菲罗啉形成配合物,使曙红Y的荧光猝灭,从而建立了测定痕量铜的荧光分析新方法。铜含量在0~250μg/L范围内与曙红Y的荧光猝灭程度呈良好的线性关系。方法的检出限为0.82μg/L;测定100μg/L铜溶液,其RSD为4.6%(n=11);样品加标回收率为102.1%~105%。本法用于人发、茶叶和大米中痕量铜的测定,结果满意。 相似文献
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本文建立了一种快速灵敏检测水中硫离子的新方法。该方法利用聚胸腺嘧啶单链DNA保护的铜纳米簇为荧光探针。以聚胸腺嘧啶单链DNA为模板制备了具有荧光性质的铜纳米簇,当加入S2-后,铜纳米簇荧光显著猝灭。铜纳米簇荧光猝灭量与S2-浓度在0.125~8μmol/L范围内有良好的线性,检测限为22nmol/L。该方法对S2-有较好的选择性,实际样品检测结果显示回收率良好,说明该方法可以用于实际水样中S2-的检测。由于聚胸腺嘧啶单链DNA为模板制备的铜纳米簇制备过程简单快速,可在5min内完成,使得检测时间大大缩短。 相似文献
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铌-桑色素荧光探针猝灭法测定核酸 总被引:4,自引:0,他引:4
探讨了应用铌-桑色素(MR)络合物作为荧光探针测定核酸的方法,最大激发峰与发射峰分别位于428nm与497nm;测定的线性范围分别为:HS DNA 10-110μg/L,CT DNA 0-30μg/L,SM DNA 5-60μg/L与Yeast RNA 200-600mg/L;相应的检出限分别为3.8、1.7、0.96与60μg/L,对络合物与DNA的吸收光谱、荧光偏振与热变性行为进行了测量。结果指出:Nb(V)-MR络合物嵌入DNA的双螺旋结构中。 相似文献
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阐释了反斯托克斯光的发光原理.根据荧光的定义,得出反斯托克斯光不属于荧光的结论.指出了仪器分析课程中存在的概念性错误,简要分析了错误原因. 相似文献
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A chip-size spectrometer is realized by combining a linear variable band-pass filter with a CMOS camera. The filter converts the spectral information of the incident light into a spatially dependent signal that is analyzed by the camera. A fluidic platform is integrated onto the spectrometer for analyzing the fluorescence from moving objects. The target is continuously excited within an anti-resonant waveguide, and its fluorescence spectrum is recorded as the object traverses the detection area. 相似文献
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壳聚糖支载有机荧光染料可在生理条件下改变其荧光特性,本文采用壳聚糖(CTS)支载有机荧光染料Cy3,利用红外光谱和热分析对产物进行了表征,研究了壳聚糖支载的荧光染料紫外吸收光谱和荧光光谱特性,结果表明,壳聚糖支载的荧光染料Cy3的紫外吸收特征峰的波长无明显变化,荧光强度明显增强,支载后的荧光染料光稳定性良好,初步细胞标记实验显示,壳聚糖支载后的Cy3染料对脑胶质瘤细胞具有良好的亲和性,并能穿透细胞膜且发出明显荧光。 相似文献
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空间分辨荧光分析技术 总被引:1,自引:0,他引:1
空间分辨荧光分析技术突破了传统荧光分析的局限,为获得空间定位信息提供了技术保障。系统地综述了构成该技术的共焦荧光法、全内反射荧光法、多光子荧光法以及近场荧光法等4种方法的原理、特点、发展及其应用,并且强调了其在单分子测定中的作用。引用文献64篇。 相似文献
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In this paper, we integrate the apparatus of electrophoresis with polarized fluorescence detection to suppress the background fluorescence arising from illuminating the coating layer of channel containers with a laser excitation source. It has demonstrated moderate background suppression efficiency, close to the ideal 3‐fold reduction on the surface doped with randomly distributed static fluorophores. In addition, when the fluorescence coverage is coated along the same orientation more uniformly, the background reduction is 10‐fold in our experiments. This detection scheme is applicable to acquire the electrophoregrams of separating small organic molecules and biopolymers, such as nucleic acids, when the loading of staining dyes is not heavy. This apparatus is simple. Only adding a pair of polarizer optics is needed. This detection scheme should work equally well with an incoherent light source. 相似文献
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Dr. Yang Zhang Dr. Yeting Zheng Yasniel Meana Prof. Françisco M. Raymo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(44):11257-11267
The borondipyrromethene (BODIPY) chromophore is a versatile platform for the construction of photoresponsive dyes with unique properties. Specifically, its covalent connection to a photocleavable group can be exploited to engineer compounds with photoswitchable fluorescence. The resulting photoactivatable fluorophores can increase their emission intensity or shift their emission wavelengths in response to switching. Such changes permit the spatiotemporal control of fluorescence with optical stimulations and the implementation of imaging strategies that would be impossible to replicate with conventional fluorophores. Indeed, BODIPYs with photoactivatable fluorescence enable the selective highlighting of intracellular targets, the nanoscaled visualization of sub-cellular components, the real-time monitoring of dynamic events and the photochemical writing of optical barcodes. 相似文献
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《Analytical letters》2012,45(9):499-504
Abstract A rapid and sensitive fluorescence test for distinguishing flavonols from flavones is reported. Under test conditions flavonoid compounds with free or glycosidated hydroxyl groups at the C3 position fluoresce; others do not. 相似文献