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1.
在pH 4.5的HAc-NaAc缓冲液中,茜素红(ARS)-镧与牛血清白蛋白(BSA)形成三元离子缔合物,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)显著增强,光谱最大散射波长分别位于373 nm 620 nm和310 nm.体系的光散射强度与BSA浓度在一定范围内呈线性增强,线性范围分别是RRS...  相似文献   

2.
在pH=5.50的HAc-NaAc缓冲体系中,低浓度的甲基蓝(MB)-铕稀土配合物的光散射较弱,将微量的美他环素(MTC)加入后体系的共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)均显著增强,且光散射信号与MTC浓度在一定范围内呈良好的线性关系,据此建立了灵敏的测定美他环素的共振瑞利散射和共振非线性散射分析法.实验以RRS法考查了甲基蓝-铕-美他环素体系形成三元离子缔合物的适宜条件、影响因素等,并初步探讨了其反应机制.  相似文献   

3.
在pH 3.2的邻苯二甲酸氢钾-HCl缓冲液中,酸性铬兰K(ACBK)-OP与牛血清白蛋白(BSA)形成三元离子缔合物,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)的显著增强,光谱最大散射波长分别位于420,678和340nm。体系的光散射强度与BSA浓度在一定范围内呈线性增强,RRS在0~3.5 mg/L,SOS在0~3 mg/L,FDS在0~3 mg/L范围内对BSA的检出限分别为0.3,0.7和0.8μg/L,据此建立了测定BSA的共振线性(RRS)和共振非线性光散射(RNLS)分析法。以RRS法考察了酸性铬兰K-OP与白蛋白形成三元缔合物的适宜条件、影响因素等。方法可用于合成样品及血清样品中蛋白含量的测定。  相似文献   

4.
宋仲容  何家洪  匡海艳  徐强 《应用化学》2010,27(12):1470-1473
在pH=4.1的HCl溶液中,Bi(Ⅲ)与茜素红和十六烷基三甲基溴化铵(CTMAB)缔合形成粒径较大的疏水性三元离子缔合物(结合比为n(Bi(Ⅲ))∶n(AR)∶n(CTMAB)=1∶3∶3),该反应导致共振光散射显著增强,最大散射峰位于364 nm。 研究了反应介质、pH值、共振探针浓度等对散射体系的影响,考察了该散射反应的稳定性及共存物质的影响,并对该三元离子缔合物的反应机理进行了探讨。 在2.5 mL 1.0×10-4 mol/L茜素红和2.0 mL 1.0×10-4 mol/L CTMAB最优试验条件下,Bi(Ⅲ)质量浓度与共振光散射强度ΔI364 nm在0~0.384 mg/L范围内呈良好线性关系,检测限为5.898×10-8 g/L,对含量为0.18 mg/L Bi(Ⅲ)溶液进行11次平行测定,其相对标准偏差为2.2%。 将该方法用于环境水样中痕量铋(质量浓度为0.552~0.831 μg/L)的测定,加标回收率为99.5%~100.2%,测定偏差小于2.7%。 基于Bi(Ⅲ)-AR-CTMAB三元离子缔合物的共振光散射光谱,建立了以茜素红染料为光谱探针的痕量Bi(Ⅲ)共振光散射检测新方法。  相似文献   

5.
在pH 5.0 NaAc-HAc介质和吐温80溶液中,研究了zn(SCN)42-与结晶紫形成的离子缔合微粒的共振散射光谱,考察了其各种影响因素和适宜的反应条件,确定了共振散射强度与Zn2+浓度的关系,建立了测定痕量zn(Ⅱ)的共振散射新方法.研究表明,在0.020~0.80μg/mL范围内,体系的共振散射强度△I与Zn...  相似文献   

6.
在pH6.0的HAc-NaAc缓冲液中,茜素红-镧与左氧氟沙星(LVFX)形成三元配合物,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)均增强,光谱最大散射波长分别位于314 nm、570 nm和285 nm,对于RRS在0.02~1.2 mg/L、SOS在0.01~1.0 mg/L和FDS在0.01~1.0 mg/L范围内呈良好的线性关系,LVFX的检出限分别为4.00μg/L(RRS法)、9.16μg/L(SOS法)和4.42μg/L(FDS法),据此建立了灵敏的测定左氧氟沙星的共振线性和非线性光散射分析法。并以RRS法考察了茜素红-镧-左氧氟沙星体系的反应条件、影响因素等。方法可用于片剂、胶囊中左氧氟沙星的测定,同时以标准加入法对尿样和血样进行了分析。  相似文献   

7.
在pH3.5的HAc-NaAc缓冲介质中,盐酸二甲双胍(MFH)与Pd(Ⅱ)形成阳离子螯合物,它能进一步与酸性染料曙红Y(EY)的阴离子反应,形成离子缔合物。三元离子缔合物的生成将引起共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)光谱显著增强,其最大散射波长分别位于292、540和327 nm。在一定范围内,三种散射信号的增强(ΔI_(RRS),ΔI_(SOS)和ΔI_(FDS))均与MFH的浓度呈线性关系。方法具有较高的灵敏度,RRS、SOS和FDS法对MFH的检出限(3σ)分别为1.7、13.2和22.7 ng·m L-1。考察了适宜的反应条件和共存物质的影响,结果表明该方法选择性良好。探讨了缔合物生成及散射增强的机理。据此,提出了简便、快速、准确且高灵敏度的测定痕量MFH的光散射新方法,并应用于片剂和尿样中MFH的测定,结果满意。  相似文献   

8.
在稀磷酸介质中,当镉(Ⅱ)与过量I-离子形成[CdI4]2-配阴离子并进一步与罗丹明B(RhB)、罗丹明6G(Rh6G)、乙基罗丹明B(ERhB)和丁基罗丹明B(BRhB)等碱性吨染料(BXD)形成离子缔合配合物[BXD]2[CdI4]时,在产生强烈共振瑞利散射(RRS)的同时,也会产生强烈的倍频散射(FDS)和明显的二级散射(SOS).在一定条件下散射强度与镉的浓度成正比.方法有高灵敏度和较好的选择性,可用于纯锌中痕量镉的测定.文中对于FDS和SOS产生的原因进行了初步的探讨.  相似文献   

9.
铑-钨酸盐-罗丹明B缔合体系的共振光散射现象及其应用   总被引:6,自引:0,他引:6  
在聚乙烯醇(PVA)存在下,Rh(Ⅲ)与钨酸盐及罗丹明B(RB)形成的离子缔合物在620nm处产生强烈的共振瑞利光散射现象,且相对于试剂空白,缔合物体系的散射光强度(ΔI)与Rh(Ⅲ)的质量浓度在0.004~0.30ng mL范围内具有良好的线性关系,据此建立的测定Rh(Ⅲ)的共振光散射法的检出限可达0 002ng mL,且大量存在的常见离子对Rh(Ⅲ)的测定不干扰。已用此方法测定了催化剂及工业产品中的铑,结果与标准方法(SnCl2法)测得值基本一致。  相似文献   

10.
在Britton-Robinson(B-R)缓冲溶液中,利福霉素类药物与ctDNA反应的适宜的pH范围是1.9~2.1.此类药物本身有微弱RRS峰,它们具有相似的光谱特征,其散射峰均在290和370 nm附近;而ctDNA的RRS峰在310 nm处.两者反应形成结合产物后其RRS明显增强,并在375nm左右出现最大散射峰,且有不同程度的红移和散射增强,说明两者结合成新的产物;加入Cu2 离子后,Cu2 与利福霉素抗生素及DNA形成三元复合物,此时将导致RRS进一步剧增,而且RRS光谱增强值与DNA浓度呈正比,因而可用于DNA测定具有较高的灵敏度,实验对ctDNA的检出限为9.7ng/mL(RFSV-Cu2 -ctDNA体系).文中研究了三元配合物反应的适宜条件和影响因素,基于此反应发展了一种用RRS技术测定DNA的新方法.  相似文献   

11.
Scattering techniques represent non-invasive experimental approaches and powerful tools for the investigation of structure and conformation of biomaterial systems in a wide range of distances, ranging from the nanometric to micrometric scale. More specifically, small-angle X-rays and neutron scattering and light scattering techniques represent well-established experimental techniques for the investigation of the structural properties of biomaterials and, through the use of suitable models, they allow to study and mimic various biological systems under physiologically relevant conditions. They provide the ensemble averaged (and then statistically relevant) information under in situ and operando conditions, and represent useful tools complementary to the various traditional imaging techniques that, on the contrary, reveal more local structural information. Together with the classical structure characterization approaches, we introduce the basic concepts that make it possible to examine inter-particles interactions, and to study the growth processes and conformational changes in nanostructures, which have become increasingly relevant for an accurate understanding and prediction of various mechanisms in the fields of biotechnology and nanotechnology. The upgrade of the various scattering techniques, such as the contrast variation or time resolved experiments, offers unique opportunities to study the nano- and mesoscopic structure and their evolution with time in a way not accessible by other techniques. For this reason, highly performant instruments are installed at most of the facility research centers worldwide. These new insights allow to largely ameliorate the control of (chemico-physical and biologic) processes of complex (bio-)materials at the molecular length scales, and open a full potential for the development and engineering of a variety of nano-scale biomaterials for advanced applications.  相似文献   

12.
Raman spectrum is a powerful analytical tool for determining the chemical information of compounds. In this study, we obtained analytical results of chlorophenols(CPs) molecules including 4-chlorophenol(4-CP), 2,6-dich- lorophenol(2,6-DCP) and 2,4,6-trichlorophenol(2,4,6-TCP) on the surface of Ag dendrites by surface-enhanced Raman scattering(SERS) spectra. SEM images indicate that the SERS substrate of Ag dendrites is composed of a large number of polygonal nanocrystallites, which self-assembled into a 3D hierarchical structure. It was found that there were distinct differences for those three molecules from Raman and SERS spectra. This indicates that SERS could be a new tool of detection technique regarding trace amounts of CPs.  相似文献   

13.
Real time synchrotron Small-Angle and Wide-Angle X-ray Scattering was performed during the tensile deformation of a high-density polyethylene copolymer. The changes of the structure in the crystalline and in the amorphous domains were followed during the three characteristic stages of the load-displacement curves: The elastic stage and the plastic range composed of the stage of the lowering load in the force-displacement-curve (yielding) and the strain hardening. Competitive phenomena like crystallite fragmentation and cavitation were found to occur simultaneously in the phase of lowering the load but at different length scale. We prove that the void formation occurs mainly during yielding. During strain hardening there was no further increase of the void volume fraction, only changes in void size.  相似文献   

14.
 Yttrium was determined by means of the resonance light scattering (RLS) technique. The characteristics of resonance light scattering spectra of yttrium-1, 6-bi(1′-phenyl-3′-methyl-5′-pyrazolone-4′-) hexanedione (BPMPHD), the effective factors and optimum conditions were studied. In the pH range of 5.0–6.1, yttrium-BPMPHD complex produces three characteristic peaks of RLS at 365, 402 and 467 nm. The enhanced intensity of RLS is proportional to the concentration of yttrium in the range of 1.0×10−8 to 1.0×10−5 mol · L−1. The limit of detection is 5.9×10−9 mol · L−1. The method has been used for the determination of Y3+ in mixed rare earths. Correspondence: Key Lab for Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China. e-mail: wux@sdu.edu.cn Received July 3, 2002; accepted October 20, 2002  相似文献   

15.
采用电化学沉积法制备了聚苯胺(Polyaniline,PANI)纳米棒、树枝状银和纳米颗粒银基体。并利用表面增强拉曼散射光谱技术(Surface-enhanced Raman Scattering,SERS)研究了PANI纳米棒的分子链在Ag金属表面的构象变化。实验结果表明由于Ag金属表面的等离子共振效应,PANI分子中N原子的孤对电子与Ag的自由电子产生共轭效应,使得PANI分子链上的电荷重新分布,结果 C—H面内弯曲振动频率和C—C键的伸缩频率向低波数方向移动(蓝移);拉曼散射频率增强的基团在金属表面倾向垂直于分子链的主轴,拉曼散射频率减弱的基团在金属表面倾向平行于分子链主轴。  相似文献   

16.
采用真空热蒸发法在自组装的单层阵列二氧化硅纳米粒子表面沉积银膜制备了帽状银纳米粒子。通过透射电镜(TEM)、扫描电镜(SEM)和紫外-可见-近红外分光光度计 (UV-Vis-NIR)对其表面形貌及光学性质进行了表征。以吡啶-(2-偶氮-4)间苯二酚作为探针分子,研究了该复合纳米粒子的表面增强拉曼散射 (SERS) 活性,增强因子高达2.88×106。结果表明在二氧化硅纳米粒子表面制备的帽状银纳米粒子是很好的表面增强拉曼散射活性基底。  相似文献   

17.
《Analytical letters》2012,45(2):221-235
ABSTRACT

The interaction of SPADNS [3-(4-sulfophenylazo)-4, 5-dihydroxy-2, 7-naphthalene disulfonic acid] with proteins in acidic solution was studied by spectrophotometric and Rayleigh light scattering (RLS) methods. SPADNS reacts rapidly with albumin at room temperature, and the intensity of the weak RLS of SPADNS was enhanced remarkably and quantitatively by this reaction.

Based on this observation, a novel RLS method for serum albumin determination was developed. The linear range is 0.125-14.9 μg/ml for BSA. The relative standard deviation (n=10) for 5.0 μg/ml BSA was 3.94%. The method was applied to the determination of proteins in human plasma, and the results were compared with the traditional proteins assay (CBB method). There is almost no interference from amino acids, metal ions and other coexistent substances. The reaction mechanism was also discussed.  相似文献   

18.
采用共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)光谱研究了阿苯达唑(ABZ)与12-磷钨酸(TP)的相互作用。在盐酸(p H 1.2)介质中,ABZ与TP反应形成离子缔合物(nABZ:nTP=3∶1),使RRS、SOS与FDS的光谱信号大大增强。在一定范围内,散射强度(ΔI)与ABZ的浓度成正比。对于ABZ的检出限(3σ)分别为1.98μg/L(RRS法)、3.75μg/L(SOS法)、5.07μg/L(FDS法),其中RRS法的灵敏度最高。文中讨论了ABZ与TP的最佳反应条件、影响因素以及共存物质的影响,还讨论了离子缔合物的结构和反应历程。据此发展了一种用RRS法快速、简便、灵敏测定ABZ的新方法。  相似文献   

19.
胡娟  张春阳 《化学进展》2010,22(8):1641-1647
表面增强拉曼散射(SERS)是一种基于拉曼散射原理识别生物及化学分子的分析方法。SERS具有灵敏度高、水干扰小、分辨率高、稳定性好等优点,广泛应用于生物分析和生物医学研究领域。近年来,SERS技术在基因分析领域得到迅速的发展,成为国内外研究的热点。本文对应用于基因分析的一些最新SERS技术(包括基因的免标记检测和标记检测)进行较为全面的综述,着重介绍了免标记检测中基于金属纳米粒子和针尖增强拉曼散射的SERS技术,标记检测中基于拉曼活性物、PCR技术、分子信标、基底和标记物的SERS信号放大技术,并概括了基因多组分检测技术及SERS技术的应用前景。  相似文献   

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