共查询到20条相似文献,搜索用时 15 毫秒
1.
A dual-wavelength resonance lighting scattering (DW-RLS) ratiometry is developed to detect anion biopolymer based on their bindings with cation surfactant. Using the interaction of Hyamine 1622 (HM) with fish sperm DNA (fsDNA) as an example, a dual-wavelength resonance light scattering (DW-RLS) ratiometric method of DNA was constructed. In Britton-Robinson buffer controlled medium, fish sperm DNA (fsDNA) could interact with Hyamine 1622 (HM), displaying significantly enhanced RLS signals. By measuring the RLS signals characterized at 300.0 nm (I300.0) and the RLS intensity ratio (I276.0/I294.0), respectively, fsDNA over a wide dynamic range of content could be detected. Typically, when HM concentration is kept at 6.0 × 10−5 mol l−1, using I300.0 could detect fsDNA over the range of 50-2000 ng ml−1 with the limit of 3.0 ng ml−1, while using I276.0/I294.0 could detect fsDNA over the range of 0.5-2500 ng ml−1 with the limit of 0.05 ng ml−1. Thus the latter so-called DW-RLS ratiometry is obviously superior to the former one. Based on the measurements of I300.0 and I276.0/I294.0 data, a Scatchard plot concerning the interaction between HM and fsDNA could be constructed and thus the binding number (n) and binding constant (K) could be available with the values of 13.5 and 1.35 × 105 mol−1 l, and 11.9 and 1.65 × 105 mol−1 l, respectively. 相似文献
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Gold nanoparticles are known for their plasmon resonance absorption (PRA) depending on their size. Our this investigation shows that plasma resonance light scattering (PRLS) signals in the corresponding PRA region could be measured using a common spectrofluorometer, and be enhanced when aggregation of gold nanoparticles occurs due to their interaction with organic small molecules (OSMs). Using captopril (Cap) as an example, we investigated the interactions of gold nanoparticles with OSMs in order to propose a general method of OSMs such as typical clinic organic drugs. In aqueous medium of pH 2.09, there are about 2.2 × 103 Cap molecules covalently binding to the surface of a 10-nm diameter gold nanoparticle through the thiol functional group of Cap, and thus forms a core-shell assembly of [(Au)31000]@[(Cap)2200], displaying strong enhanced PRLS signals in the PRA region of gold colloid. The PRLS intensities characterized at 553.0 nm were found to be proportional to the concentration of Cap over the range of 0.1-1.7 mg L−1 with the determination limit (3σ) of 32.0 μg L−1. With that, Cap in pharmaceutical preparations could be determined with the recovery of 97.0-104.5% and R.S.D. of less than 2.4%. 相似文献
3.
Spectral assignments to the light emissions of fluorescent organic small molecules in aqueous medium
Spectrofluorometric identifications of artificial organic dyes have important environmental significance, but both scattered light signals and the fluorescence signals were twins in fluorospectroscopy, and the light scattering signals are always the interference sources of spectrofluorometry. In order to investigate the relationship between the light scattering and fluorescence in the spectrofluorometric measurements, herein we discuss the scattered light and fluorescence emission properties of organic small molecules (OSMs) using Lignin Pink (LP) in neutral medium as an example. With the help of UV-vis measurements, and starting from three-dimensional light emission measurements, scattered light and fluorescence emissions could be assigned. Investigations by increasing LP concentration showed that the light emission at 282.0 and 344.0 nm could be attributed to the resonance light scattering (RLS) signals and that at 420.0 and 570.0 nm are composed of both RLS and fluorescence emissions, respectively. UV-vis measurements showed that LP does not have the tendency of aggregation, and the strong RLS signals should be ascribed to the large hydrodynamic diameter of LP itself in aqueous medium, supported by dynamic light scattering (DLS) measurements. 相似文献
4.
应用双波长共振光散射比率法(DW-RLS)研究了甲基紫与苋菜红之间的相互作用.在pH 1.24的乙酸钠-HCl缓冲溶液中,甲基紫和苋菜红本身的共振光散射(RLS)信号均很弱,但是当它们相互作用形成缔合物时,导致RLS信号明显增强并出现新的RLS光谱,适当浓度的Triton X-100存在使结合反应敏化,缔合物最大散射峰位于528 nm,RLS信号强度与苋菜红的浓度呈线性关系.通过测量528 nm处的RLS强度或两个波长处RLS强度比值(I417/I343),可对苋菜红进行定量检测.当溶液中甲基紫的浓度为1.54×10-5 mol/L时,RLS法测定苋菜红的线性范围和检出限分别为0.05~0.50 μg/mL和0.02 μg/mL,而DW-RLS法的线性范围和检出限分别为0.01~0.60 μg/mL和1 ng/mL,与RLS法相比较,DW-RLS法受酸度、离子强度等环境条件影响较小,并且有更宽的线性范围和更低的检出限. 相似文献
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Zhanguang Chen Weifeng Ding Fenglian Ren Jinbin Liu Yizeng Liang 《Analytica chimica acta》2005,550(1-2):204-209
A new assay of nucleic acids at nanogram level was established based on the enhanced resonance light scattering (RLS) signals of two zwitterionics cocamidopropyl hydroxysultaine (HSB) and lauryl betaine (BS-12). Under optimum conditions, the weak RLS signal of HSB is enhanced by nucleic acids, and the enhanced RLS intensity is proportional to the concentration of nucleic acids in the range of 0.02–7.3 mg l−1 for calf thymus DNA and 0.01–8.6 mg l−1 for fish sperm DNA. The detection limits were 1.5 ng ml−1 for calf thymus DNA and 1.9 ng ml−1 for fish sperm DNA. Plasmid DNA extracted from K-12-HB101 colt was determined with satisfactory results. 相似文献
8.
A novel free-probe assay of dextrin was established based on the resonance light scattering (RLS) enhancement in aqueous solution due to the self-aggregation of dextrin. The RLS intensity was well proportional to the concentration of dextrin over the wide range 0.2-14 μg mL−1 and a detection limit 0.02 μg mL−1 was obtained in the optimum conditions. The effect factors such as pH, buffer medium, holding time, ionic strength and temperature were studied in detail. Little or no interference was presented in the detection when adding coexisting substances including various metal ions and some saccharine in the solution. The assay proposed owns the advantages of easy operation, rapidity, sensitivity and practicability. Three synthetic samples and three kinds of medicine samples were analyzed with satisfactory results. 相似文献
9.
Qie Gen Liao 《Talanta》2007,71(2):567-572
Any signals, if their intensities have simple functional relationship with analyte concentration, can be applied to analytical purposes. Rayleigh light scattering signals and fluorescence signals are twins in flurospectroscopy, so the light scattering signals are the major interference when the Stokes shift is small. Herein, we propose a light scattering and fluorescence emission (LS-FL) coupled ratiometry using CdS quantum dots (QDs) as a fluorescence probe to detect aminoglycoside antibiotics (AGs). As model analytes, AGs, when attached to the surface of CdS-QDs via electrostatic interaction in aqueous medium, result in strong enhanced light scattering (LS) emission characterized at 376 nm and fluorescence quenching of CdS-QDs at 500 nm. Thus, a ratiometry using the coexistent light scattering and fluorescent emission signals has been proposed. Based on the linear relationship between logarithm of light scattering and fluorescence emission ratio (R) and logarithm of AGs concentration, a novel assay of AGs is established with the limits of detection (3σ) being 58-190 nmol l−1, and applied successfully to detect AGs injection and serum samples. 相似文献
10.
Cruz Enriquez A Rivero Espejel IA Andrés García E Díaz-García ME 《Analytical and bioanalytical chemistry》2008,391(3):807-815
The interaction of 11-mercaptoundecanoic acid capped gold nanoparticles (MUA-GNPs) with europium ions and aminoacids has been
studied by UV-Vis spectrophotometry, fluorescence, confocal fluorescence microscopy, resonance light scattering and TEM. Results
demonstrated that hyper-Rayleigh scattering emission occurs upon the addition of lysine to the MUA-GNPs–Eu(III) system, thus
providing an inherently sensitive method for lysine determination. The effects of geometrical factors of the gold nanoparticles
(aspect ratio, particle size, cluster formation) and the surrounding medium (pH) on this behavior are discussed. The cooperative
binding interactions of Eu3+ and lysine with gold nanoparticles permitted the discrimination of lysine from other amino acids. The probable mechanism
for the spectral changes and the enhanced resonance light scattering observed is outlined.
Figure Gold nanoparticle resonance light scattering plasmon enhancement through cooperative binding with europium and lysine 相似文献
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A sensitive, highly specific immunoassay method has been developed by measuring the enhanced resonance light scattering (RLS) signals of immunoreactions with simultaneously scanning both the excitation and the emission monochromators of a common spectrofluorometer. For a given content of antibody (Ab), the RLS signals of an immunoreaction follow Gaussian distribution with antigen (Ag) concentration. The central position of the Gaussian curve represents the concentration of given Ab, and the half bandwidth has proved to be a characteristic constant of a given Ab-Ag immunoreaction. With the RLS signals, the limit of detection for human immunoglobulin G (HIgG) in serum samples could reach 10 ng ml−1, and the concentration of HIgG in blood serum samples could be detected with the recovery of 90.2-107.7% and R.S.D. of 0.8-2.7%. The results of determination for three human serum samples are identical to those obtained by immunoturbidimetry. 相似文献
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A novel assay of DNA has been proposed by using ferric nanoparticles as probes coupled with resonance light scattering (RLS) detection. At pH 7.40, the RLS intensity of ferric nanoparticles can be greatly enhanced by the aggregation of positively charged ferric nanoparticles through electrostatic interaction with negatively charged DNA. The enhanced intensity of RLS at 452 nm is proportional to the concentration of DNA in the range of 0.01-0.8 μg ml−1 for calf thymus and salmon sperm DNA and in the range of 0.005-0.3 μg ml−1 for E. coli K12 genomic DNA. Detection limits are 3.6 ng ml−1 for calf thymus DNA, 4.4 ng ml−1 for salmon sperm DNA, and 1.9 ng ml−1 for E. coli K12 genomic DNA, respectively. Compared with the chromophores previously used in RLS assay, the ferric nanoparticles have offered several advantages in easy preparation, good photostability and high sensitivity without being modified or functionalized. 相似文献
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自从Pasternack[1,2]使用普通荧光分光光度计建立共振光散射(RLS)技术以来,人们用该技术建立了十分灵敏的蛋白质和核酸的分析方法[3,5]。同时该技术在研究化合物在溶液中的聚集态方面也有了较为广泛的应用,一般认为分子聚集体的形成是引起RLS增强的主要原因[6]。已知甲醇、乙醇与水互溶形成均匀的溶液体系,那么在这些溶液体系中是否也存在某种形式的分子聚集体呢?为此本文研究了不同浓度的甲醇水溶液和乙醇水溶液的RLS光谱。1 实验部分1 1 试剂和仪器甲醇(上海建鑫化工试剂厂,分析纯,含量%≥99 5);乙醇(安徽特酒总… 相似文献
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Ellagic acid (EA) reacted with Gemini zwitterionic surfactant, phosphodiesters quaternary ammonium salt (PQAS), and formed fine particles which produced strong enhancement in intensity of resonance light scattering (RLS). The effects of several factors on the RLS signal, such as pH, ionic strength, PQAS concentration and so on, were optimized. The relationship between enhanced RLS intensity and EA concentration was constructed. A novel and rapid method for the determination of EA was built. The linear range of this method was 0.016-4.0 μg mL−1 and the detection limit was 13.9 ng mL−1. Under the optimum conditions, the proposed method was applied to determine EA in body fluids with the results of quantitative recoveries between 98.4-101.4% in human serum samples and 99.1-102% in human urine samples. This method characterized by low limit detection is very sensitive and the cost is low, and constitutes a fast one-step procedure which requires only measuring the RLS intensities. The mechanism of the reaction was also studied. This investigation could contribute to the research on the delivery and release of bioactive molecules by Gemini surfactants. 相似文献
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A new resonance light scattering (RLS) spectrometric method for mercury ions (Hg2+) in aqueous solutions with sulfur ion (S2−) modified gold nanoparticles (Au-NPs-S) has been developed in this contribution. It was found that S2− at the surface of Au-NPs resulting from the surface modification can interact with Hg2+ to form very stable S-Hg-S bonds when Hg2+ concentration is lower than that of S2−, resulting in the aggregation of Au-NPs-S and causing enhanced RLS signals. The enhanced RLS intensities (ΔIRLS) characterized at 392 nm were found to be proportional to the concentration of Hg2+ in the range of 0.025-0.25 μmol L−1 with a detection limit (3σ) of 0.013 μmol L−1. Our results showed that this approach has excellent selectivity for Hg2+ over other substances in aqueous solutions. 相似文献
18.
A rapid and sensitive method for the determination of proteins is proposed based on the measurements of the enhanced resonance light scattering (RLS) spectroscopy of sodium lauroyl glutamate (SLG). Under the optimum conditions, the interaction between SLG and proteins occurred rapidly, resulting in greatly enhanced RLS intensity with the maximum peak located at 394 nm. It was found that the enhanced RLS intensities were in proportion to the concentrations of proteins in the range of 0.01-3.1 μg ml−1 depending on the kind of proteins. The detection limits were below 6 ng ml−1. Compared with some other methods for the determination of proteins, this method shows high sensitivity, low detection limit and simplicity. This is an inexpensive, simple and fast one-step procedure which requires only measuring the RLS intensities. Human serum samples were determined with satisfactory results. 相似文献
19.
Determination of deoxyribonucleic acids by a resonance light scattering technique and its application 总被引:3,自引:0,他引:3
Jie N Jia G Hou S Xiong Y Dong Y 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(14):3295-3301
For the first time, acetamiprid has been used to determine nucleic acid (DNA) using the resonance light scattering (RLS). The RLS of acetamiprid was greatly enhanced by DNA in the range of pH 1.6-1.8. A RLS peak at 313 nm was found, and the enhanced intensity of RLS at this wavelength was proportional to the concentration of DNA. The linear range of the calibration curve was 0-11.0 microg ml(-1) with the detection limit of 20 ng ml(-1). The nucleic acids in synthetic sample and in rice seedling extraction were determined satisfactorily. The interaction mechanism of acetamiprid and DNA is discussed. Mechanism studies show that the enhanced RLS is due to the aggregation of acetamiprid in the presence of DNA. 相似文献
20.
Determination of trace proteins with pyronine Y and SDS by resonance light scattering 总被引:1,自引:0,他引:1
A new resonance light scattering (RLS) probe for determining proteins is presented. The weak RLS of pyronine Y–SDS can be
enhanced substantially by adding proteins in the presence of H2SO4, resulting in a strong and wide RLS band in the region 310–425 nm. The interaction of pyronine Y–SDS with proteins was studied
on the basis of this behavior and a new quantitative method was developed for determining proteins. The enhanced RLS intensity
is proportional to the concentration of proteins in the range 0.15–3.6 μg mL−1 for bovine serum albumin (BSA) and 0.06–4.8 μg mL−1 for human serum albumin (HSA), with detection limits of 21.0 and 12.0 ng mL−1, respectively. This method is characterized by high sensitivity, rapidity of reaction, and simplicity. Four synthetic samples
were determined satisfactorily and recovery was 99.5–101.5%. Results for human serum and urine samples were in agreement with
those obtained by the Bradford method, with relative standard deviations (RSD) of 1.5–3.1%. 相似文献