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1.
崔志平  刘绍璞  刘忠芳  胡小莉 《应用化学》2011,28(11):1331-1336
在pH=10.0的Britton-Robinson(BR)缓冲溶液中,多菌灵与Pd(Ⅱ)反应形成1∶1的六元螯合物,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)显著增强,并产生新的共振瑞利散射光谱,其最大RRS、SOS和FDS波长分别位于309、606和310 nm。 在一定范围内,3种散射增强(ΔIRRS、ΔISOS和ΔIFDS)均与多菌灵的浓度成正比,反应具有较高的灵敏度,对于多菌灵的检出限分别为7.1×10-9 g/mL(RRS)、7.4×10-9 g/mL(SOS)和10.7×10-9 g/mL(FDS)。 据此提出了测定多菌灵的光散射新方法。 以灵敏度最高的RRS法为例,测定了西芹和市售农药中多菌灵的含量,结果与标准方法一致。 文中还对反应机理和散射增强的原因进行了讨论。  相似文献   

2.
在pH=1.5的HCl介质中,阿苯达唑(ABZ)与12-磷钨酸(TPA)形成摩尔比为3∶1的离子缔合物,从而引起共振瑞利散射(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372nm、726nm和392nm。在一定范围内,三种散射信号的增强(△IRRS、△ISOS和△IFDS)均与ABZ的浓度呈线性关系。方法具有较高的灵敏度,RRS、SOS和FDS法对ABZ的检出限(3σ)分别为1.0ng/mL、3.7ng/mL和2.5ng/mL。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。据此,提出了简便、快速、准确且高灵敏度的测定痕量ABZ的光散射新方法,并应用于片剂和尿样中ABZ的测定。  相似文献   

3.
在pH=3.5的HAc-NaAc介质中,呋塞米(FUR)与Ag(Ⅰ)形成1:1(摩尔比)的螯合物,从而引起共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)光谱显著增强,其最大RRS,SOS和FDS波长分别位于310,584和330 nm.在一定范围内,3种散射信号的增强(△ⅠRRs,△ⅠSOS和△ⅠFDS...  相似文献   

4.
孙谦  杨迎春  叶芝祥  张林 《应用化学》2013,30(4):474-480
在pH=9.0的弱碱性环境中,Hg2+与邻菲啰啉(phen)反应形成无色螯合物[Hg(phen)3]2+,再与刚果红(CR)反应,形成三元离子缔合物Hg(phen)3CR,其摩尔比为1∶1。 此时引起共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)光谱显著增强,最大的散射波长分别位于578 nm(RRS法)、612 nm(SOS法)和352 nm(FDS法)。 在一定条件下,散射增强(ΔI)与Hg2+浓度呈良好的线性关系,检出限分别为2.32 μg/L(RRS法)、3.20 μg/L(SOS法)和1.56 μg/L(FDS法),考察了最佳实验条件和影响因素,表明本方法具有良好的选择性,并以RRS法为例研究了共存物质的影响。 据此建立了灵敏度高、选择性好、快速准确测定Hg2+的光散射新方法,该方法用于环境水样中Hg2+的测定取得满意结果。 并对RRS增强的原因和反应机理进行了讨论。  相似文献   

5.
用共振Rayleigh散射(RRS)、倍频散射(FDS)、二级散射(SOS)并结合吸收光谱研究了刚果红(CR)与阿米卡星(AMK)的相互作用. 在弱酸性条件下, CR与AMK借静电引力、疏水作用力和电荷转移作用形成1︰1离子缔合物, 导致RRS, FDS和SOS光谱显著增强, 并出现新的RRS, FDS和SOS光谱. 最大RRS, FDS和SOS分别位于563, 475和940 nm, 散射强度在一定范围内与AMK的浓度成正比. 此方法具有很高的灵敏度, 对于AMK的检出限(3σ)分别为4.0 ng·mL-1 (RRS法), 3.6 ng·mL-1 (FDS法), 1.9 ng·mL-1 (SOS法). 此方法也有较好的选择性. 据此发展了一种用刚果红测定AMK的共振散射新方法. 并用于人血清和尿液中AMK的测定, 回收率在95.5%~105.5%之间. 采用量子化学方法计算了反应前后生成焓、电荷分布、平均极化率等的变化, 探讨了反应机理和散射光谱产生及增强的原因.  相似文献   

6.
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   

7.
在0.05 mol/L(pH 1.3)的 HCl 介质中,十二烷基苯磺酸钠(SDBS)与亚甲蓝(MB)借静电引力和疏水作用力形成 2︰1 的离子缔合物,导致溶液共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)急剧增强,并产生新的 RRS,SOS 和 FDS 光谱。最大 RRS, SOS 和 FDS 分别位于 310, 647 和 341 nm, 散射强度在一定范围内与MB的浓度成正比,方法具有很高的灵敏度,对于MB的检出限(3?)分别为 1.2 ng/mL (RRS法)、1.4 ng/mL (SOS法) 和 1.7 ng/mL (FDS法)。据此发展了一种测定痕量亚甲蓝的新方法。用于人血清样品中亚甲蓝含量的检测,回收率在 94.4-103.7 ? 之间。实验优化了反应条件,考察了共存物质的影响,并结合量子化学AM1法讨论了反应机理和散射光谱产生及增强的原因。  相似文献   

8.
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   

9.
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   

10.
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   

11.
In 0.1 mol/L HCl medium, 12-tungstophosphoric(TP) acid reacted with matrine(Mat) and oxymatrine(Oxy) to form an ion-association complex. As a result, the new spectra of resonance Rayleigh scattering(RRS), second-order scattering(SOS) and frequency doubling scattering(FDS) appeared and their intensities were enhanced greatly. The maximum scattering wavelengths of RRS, SOS and FDS were located at 370, 670 and 390 nm, respectively. The increments of scattering intensity were directly proportional to the concentration of Mat and Oxy in a certain range. Based on this, the method for the determination of matrine and oxymatrine has been established. It has been applied to the determination of matrine and oxymatrine in samples of Radix sophorae flavescentis with satisfactory result. The reaction mechanism and reasons of RRS enhancement were discussed.  相似文献   

12.
In 0.1 molL(-1) (pH 1.0) HCl medium, 12-tungstophosphoric acid (TP) reacted with malachite green (MG) to form an ion-association complex. As a result, the new spectra of RRS, SOS and FDS appeared and their intensities were enhanced greatly. The maximum wavelengths of RRS, SOS and FDS were located at 334 nm, 586 nm and 330 nm, and the scattering intensities were proportional to the concentration of MG. Based on it a new method for the determination of MG has been established. The detection limits (3σ) of these methods were in the range of 3.7-27 ng mL(-1). The RRS, SOS, and FDS characteristics, absorption spectrum characteristics and optimum reaction conditions of the system were discussed. Effects of coexistent substances were tested, and the results demonstrated that this method had good selectivity. It has been applied to the determination of malachite green residues in fish flesh with satisfactory results. The reaction mechanism and reasons of RRS enhancement are discussed.  相似文献   

13.
《Analytical letters》2012,45(4):637-647
Three new methods for the determination of trace amounts of sodium alginate (SA) based on the reaction of SA with cetyltrimethylammonium bromide (CTAB) by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS), and second-order scattering (SOS) have been investigated. The SA can react with CTAB in a pH 10.0 Britton–Robinson buffer to form a new product, which can lead to a significant enhancement of RRS, FDS, and SOS intensities and appearance of new spectra. The maximum scattering wavelengths, λex/λem, appear at 351 nm/351 nm for RRS, 240 nm/480 nm for SOS, and 870 nm/435 nm for FDS, respectively. The increments of the scattering intensities (ΔI) are proportional to the concentration of SA in a certain range. The detection limits (3σ) for SA are 3.69 ng mL?1 for the RRS method, 6.91 ng mL?1 for the FDS method, and 7.45 ng mL?1 for the SOS method under optimum conditions. The proposed methods were applied to the determination of SA in real samples with satisfactory results.  相似文献   

14.
In pH 0.6-1.1 HCl-NaAc buffer solution, torasemide (TOR) reacted with TP to form a 3:1 ion-association complexes. As a result, not only the absorption spectra were changed, but also the intensities of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) were enhanced greatly. The maximum RRS, SOS and FDS wavelengths were located at 370, 333, 776 nm, respectively. Under given conditions, the intensities of RRS, SOS and FDS were all directly proportional to the concentration of TOR. The detection limits of RRS, SOS and FDS were 0.7173 ng mL(-1), 7.007 ng mL(-1) and 10.90 ng mL(-1). The optimum conditions and the effects of coexisting substances on the reaction were investigated. The results showed that the method had good selectivity. Therefore, a highly sensitive, simple and quick method has been developed for the determination of TOR. The method can be applied satisfactorily to the determination of TOR in tablets and urine samples.  相似文献   

15.
The interaction between congo red (CR) and amikacin (AMK) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium, CR combined with AMK to form an ion association complex with the composition ratio of 1∶1 by electrostatic interaction, hydrophobicity and charge transferring effect. As a result, the new spectra of RRS, FDS, and SOS appeared and their intensities were enhanced greatly. The maximum wavelengths of RRS, FDS and SOS were located at 563 nm, 475 nm and 940 nm, and the scattering intensities were proportional to the concentration of AMK. These three methods have very high sensitivities, and the detection limits were 4.0 ng·mL?1 for RRS, 3.6 ng·mL?1 for FDS and 1.9 ng·mL?1 for SOS, respectively. At the same time, the methods have better selectivity. A new method for the determination of trace amounts of AMK with congo red by resonance scattering technique has been developed. The recovery for the determination of AMK in blood serum and urine sample was between 95.5% and 105.5%. In this study, the properties, such as enthalpy of formation, charge distribution and mean polarizability, were calculated by AM1 quantum chemistry method. In addition, the reaction mechanism and the reasons for the enhancement of scattering spectra were discussed.  相似文献   

16.
在pH 5.9 NaAc-HAc的缓冲溶液中,法莫替丁(FMTD)与Hg(II)形成五元环螯合阳离子([Hg(FMTD)]2+),再进一步与十二烷基硫酸钠(SLS),十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)等阴离子表面活性剂(AS)反应形成1: 1: 2的三元混配物([Hg(FMTD)(AS)2]). 此时,引起体系共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)的显著增强. 最大的散射波长位于345~352 nm (RRS法)、544 nm (SOS法) 和352 nm (FDS法),3种散射强度(?I)的顺序均为SLS>SDS>SDBS,在一定范围内?I与FMTD的浓度成良好的线性关系,检出限为3.3~3.9 ng/mL (RRS法)、14.6 ~ 16.3 ng/mL (SOS法)和7.0 ~ 8.5 ng/mL (FDS法). 据此提出了灵敏度高、选择性好、快速准确测定FMTD的光散射新方法. 适用于注射液、血清和尿样中FMTD含量的测定. 文中探讨了[Hg(FMTD)(AS)2]的形成对吸收和RRS光谱的影响及引起RRS增强的原因.  相似文献   

17.
Liquid phase gold nanoparticles with different diameters and colors can be prepared using sodium citrate reduction method by controlling the amounts of sodium citrate. The mean diameters of gold nanoparticles are measured by transmission electron microscope (TEM). Gold nanoparticles with different sizes have specific absorption spectra. When the diameters of nanoparticles is between 12 and 41 nm, the maximum absorption peaks locate at 520-530 nm and there are red shifts gradually with the increase of diameters of gold nanoparticles. And when the size of gold nanoparticle is constant, the absorbance is proportional to the concentration of gold. Obvious resonance Rayleigh scattering (RRS) and the resonance non-linear scattering such as second-order scattering (SOS) and frequency-doubling scattering (FDS) appear at the same time as well, and the maximum scattering peaks are located at 286 nm (RRS), 480 nm (SOS) and 310 nm (FDS), respectively. When the concentration of gold is constant, absorbance and the intensities of RRS, SOS and FDS (I(RRS), I(SOS) and I(FDS)) have linear relationships with the diameters of gold nanoparticles. When the diameter of gold nanoparticle is constant, the absorbance and I(RRS), I(SOS), I(FDS) are directly proportional to the concentrations of gold nanoparticles. Therefore, it is very useful for studying the liquid phase gold nanoparticles by investigating the absorption, RRS, SOS and FDS spectra.  相似文献   

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