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1.
《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   

2.
When trypsin reacts with Herring sperm DNA (hsDNA), Salmon sperm DNA (sDNA), and Calf thymus DNA (ctDNA) to form a complex, the resonance Rayleigh scattering (RRS) was remarkably enhanced and new RRS spectra appear. These new spectra have similar characteristics of RRS spectra. The maximum RRS peaks are at 307 nm (hsDNA, sDNA) and 290 nm (ctDNA), and other peaks are at 350 nm. The scattering intensity is proportional to the concentration of DNA or trypsin; so this intereaction can be used to determine trypsin using DNA or DNA using trypsin. In the determination of DNA using trypsin, the linear ranges for hsDNA, sDNA, and ctDNA are 0–2.3, 0–2.5, and 0–1.9 μg·mL−1, and the detection limits are 0.4, 0.7, and 1.1 ng·mL−1, respectively. In the determination of trypsin using hsDNA, the linear range is 0–30.0 μg·mL−1, and the detection limit is 39.0 ng·mL−1. In this paper, the intereaction conditions were optimized. The affecting factors, chemical properties of the complex, and the composition ratio of trypsin with DNA were investigated. Using trypsin as RRS probe, a sensitive method for the determination of trace amounts of DNA was developed. Translated from Chemical Journal of Chinese Universities, 2006, 27(3) (in Chinese)  相似文献   

3.
In pH 4.9 Britton-Robinson buffer solution, methotrexate (MTX) reacted with thallium(III) to form a 3∶1 chelate. This resulted in great enhancement of second-order scattering (SOS) spectra and frequency doubling scattering (FDS) spectra and appearance of new SOS and FDS spectra. Their maximum wavelengths were located at 520 and 390 nm, respectively. The increments of scattering intensities (ΔI) were directly proportional to the concentrations of MTX in the ranges of 0.022—2.0 μg•mL-1 (SOS method) and 0.008—2.5 μg•mL-1 (FDS method). The methods exhibited high sensitivities. The detection limits for MTX were 7.4 ng•mL-1 (SOS method) and 2.3 ng•mL-1 (FDS method), respectively. The optimum conditions of the reaction, the influencing factors and the effects of coexisting substances were investigated. A highly sensitive, simple and fast method for the determination of MTX has been developed. The method can be applied satisfactorily to the determination of MTX in human serum samples. In this work, the charge distribution of MTX was calculated by a CNDO quantum chemistry method. In addition, the reaction mechanism was discussed.  相似文献   

4.
In pH 4.5–7.0 Britton-Robinson buffer solution, furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic chelate. This chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV), crystal violet (CV), methyl violet (MV), methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association complexes. This not only resulted in the change of absorption spectra, but also led to the significant enhancement of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS). The maximum RRS wavelengths were located at 324 nm for the EV, CV and MV system, and 340 nm for the BG and MeG system. The maximum SOS wavelengths were located at 550 nm for the EV, CV, BG and MeG system, and 530 nm for the MV system. The maximum scattering peaks of all the systems were at 392 nm for FDS. The enhanced RRS, SOS and FDS intensities were directly proportional to the concentration of FUR. The detection limits for the different dye systems were 0.3–4.9 ng mL?1 for the RRS method, 3.2–33.1 ng mL?1 for the SOS method and 9.0–85.7 ng mL?1 for the FDS method. These methods could be used for the determination of trace amounts of FUR. The effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption, RRS, SOS and FDS have been investigated. The optimum conditions of these reactions, the influencing factors and the analytical properties have been tested. The influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high sensitivity. Based on the aforementioned research, the highly sensitive, simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established, which could be applied to the determination of FUR in tablet, injection, human serum and urine samples. The composition and structure of the ternary ion-association complex and the reaction mechanism were discussed.  相似文献   

5.
CdTe nanocrystals (CdTe NCs) were achieved by reaction of CdCl2 with KHTe solution and were capped with sodium mercaptoacetate. The product was detected by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS), fluorescence spectra, ultraviolet-visible spectra and X-ray diffraction (XRD). The CdTe NCs are of cubic structure and the average size is about 5 nm. The fluorescence quantum yield of CdTe NCs aqueous solution increased from 37% to 97% after 20 d under room light. The maximum λ em of fluorescence changed from 543 nm to 510 nm and the blue shift was 33 nm. CdTe NCs aqueous solution can be steady for at least 10 months at 4 in° a refrigerator. The resonance Rayleigh scattering (RRS) of CdTe NCs in the aqueous solution was investigated. The maximum scattering peak was located at about 554 nm. The interactions of CdTe NCs with amikacin sulfate (AS) and micronomicin sulfate (MS) were investigated respectively. The effects of AS and MS on fluorescence and RRS of CdTe NCs were analyzed. It was found that AS and MS quenched the photoluminescence of CdTe NCs and enhanced RRS of CdTe NCs. Under optimum conditions, there are linear relationships between quenching intensity (F 0-F), intensity of RRS (I-I 0) and concentration of AS and MS. The detection limits (3б) of AS and MS are respectively 3.4 ng·mL−1 and 2.6 ng·mL−1 by the fluorescence quenching method, and 15.2 ng·mL−1 and 14.0 ng·mL−1 by the RRS method. The methods have high sensitivity, thus CdTe NCs may be used as fluorescence probes and RRS probes for the detection of aminoglycoside antibiotics. Supported by the National Natural Science Foundation of China (Grant No. 20475045)  相似文献   

6.
金纳米微粒作探针共振瑞利散射光谱法测定卡那霉素   总被引:18,自引:0,他引:18  
在一种含柠檬酸盐的溶液中, 柠檬酸根阴离子自组装于带正电荷的金纳米微粒表面, 使金纳米微粒成为一种被柠檬酸根包裹的带负电荷的超分子化合物. 在pH 4.4~6.8的弱酸性介质中, 它可与质子化的卡那霉素(KANA)阳离子借静电引力、疏水作用力结合, 形成粒径更大的聚集体(平均粒径从12增至20 nm), 这种聚集体的形成在引起金纳米的等离子体吸收带明显红移(Δλ=102 nm)的同时, 共振瑞利散射(RRS)显著增强并且倍频散射(FDS)和二级散射(SOS)等共振非线性散射也有较大的增强, 最大散射峰分别位于280 nm (RRS), 310 nm (FDS)和480 nm (SOS)处. 在适当条件下, 散射强度(ΔI)与卡那霉素的浓度成正比, 其中RRS法灵敏度最高, 因此金纳米微粒可作为测定卡那霉素的高灵敏RRS探针, 它对卡那霉素的检出限为10.52 ng•mL-1, 方法有较好的选择性, 可用于血液中卡那霉素的测定, 文中还讨论了有关反应机理和RRS增强的原因.  相似文献   

7.
在pH为5.0-5.4的乙酸-乙酸钠缓冲溶液中,克林霉素(Clin)与钯(Ⅱ)形成螯合阳离子,它能进一步与二碘荧光素(DIF),赤藓红(Ery),曙红Y(EY)等卤代荧光素类染料反应形成1:1:1的三元离子缔合物,此时将引起吸收光谱变化和荧光猝灭,同时还导致共振瑞利散射(RRS)的急剧增强并产生新的RRS光谱,钯(Ⅱ)-克林霉素与DIF,Ery和EY形成产物的最大散射波长分别位于285,287,32 1nm处,另外还有些较弱的散射峰存在。散射增强(ΔI)与克林霉素浓度在一定范围内成正比,可用于克林霉素的定量测定。对于DIF,Ery和EY体系的线性范围和检出限分别为0.025-2.1μg•mL-1和7.8 ng•mL-1,0.053-2.4μg•mL-1和16.0 ng•mL-1;以及0.038-2.4μg•mL-1和11.0 ng•mL-1。本文研究了适宜的反应条件,考察了共存物质的影响,表明方法有较好的选择性,基于三元离子缔合物的RRS光谱,发展了一种高灵敏、简便快速测定克林霉素的新方法。文中还对离子缔合物的组成,结构和反应机理,以及离子缔合物对吸收,荧光和RRS光谱的影响进行了讨论。  相似文献   

8.
In pH 6.6 Britton–Robinson buffer medium, the CdS quantum dots capped by thioglycolic acid could react with aminoglycoside (AGs) antibiotics such as neomycin sulfate (NEO) and streptomycin sulfate (STP) to form the large aggregates by virtue of electrostatic attraction and the hydrophobic force, which resulted in a great enhancement of resonance Rayleigh scattering (RRS) and resonance non-linear scattering such as second-order scattering (SOS) and frequency doubling scattering (FDS). The maximum scattering peak was located at 310 nm for RRS, 568 nm for SOS and 390 nm for FDS, respectively. The enhancements of scattering intensity (ΔI) were directly proportional to the concentration of AGs in a certain ranges. A new method for the determination of trace NEO and STP using CdS quantum dots probe was developed. The detection limits (3σ) were 1.7 ng mL−1 (NEO) and 4.4 ng mL−1 (STP) by RRS method, were 5.2 ng mL−1 (NEO) and 20.9 ng mL−1 (STP) by SOS method and were 4.4 ng mL−1 (NEO) and 25.7 ng mL−1 (STP) by FDS method, respectively. The sensitivity of RRS method was the highest. The optimum conditions and influence factors were investigated. In addition, the reaction mechanism was discussed.  相似文献   

9.
In pH 6.0-11.2 Britton-Robinson buffer solution, binding of heparin with crystal violet (CV) can result in a significant enhancement of resonance Rayleigh scattering (RRS) and resonance non-linear scattering, such as frequency doubling scattering (FDS) and second-order scattering (SOS). Their maximum scattering wavelengths, λex/λem, appear at 492 nm/492 nm for RRS, 984 nm/492 nm for FDS and 492 nm/984 nm for SOS, respectively. The optimum conditions of the reaction, the influencing factors and the relationship between the three scattering intensities and the concentration of heparin have been investigated. New methods for the determination of trace amounts of heparin based on the RRS, FDS and SOS methods have been developed. The methods exhibit high sensitivities, the detection limit for heparin is 2.9 ng ml−1 for the RRS method, 3.5 ng ml−1 for the FDS method and 3.3 ng ml−1 for the SOS method. The methods have good selectivity and were applied to the determination of heparin in heparin sodium injection samples with satisfactory results.  相似文献   

10.
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   

11.
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   

12.
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   

13.
王芬  刘忠芳  刘绍璞 《化学学报》2005,63(21):1991-1998
在pH 2.5左右的酸性介质中, 刚果红与表柔比星、柔红霉素和米托蒽醌等蒽环类抗生素反应形成离子缔合物时, 仅能引起吸收光谱和荧光光谱的微小变化, 但却能导致共振瑞利散射(RRS)的显著增强并产生新的RRS光谱, 与此同时也观察到二级散射(SOS)和倍频散射(FDS)的增强. 最大RRS峰位于370 nm附近, 并在280 nm附近有另一散射峰. 而它们的SOS峰均在530 nm附近, 最大FDS峰均位于353 nm处. 其中RRS法灵敏度最高, 它对表柔比星、柔红霉素和米托蒽醌的检出限分别为0.054, 0.058和0.033 μg/mL, 而其线性范围分别为0.05~12.0, 0.05~12.0和0.04~7.5 μg/mL. 文中研究了反应产物的吸收、荧光和RRS光谱特征, 适宜的反应条件及分析化学性质, 据此发展了一种用RRS技术灵敏、简便、快速测定蒽环类抗癌药物的新方法.  相似文献   

14.
Liu SP  He YQ  Liu ZF  Kong L  Lu QM 《Analytica chimica acta》2007,598(2):304-311
When gold nanoparticles were being prepared by sodium citrate reduction method, citrate anions self-assembled on the surface of gold nanoparticles to form supermolecular complex anions with negative charges, and protonated raloxifene (Ralo) was positively charged and could bind with the complex anions to form larger aggregates through electrostatic force and hydrophobic effects, which could result in the remarkable enhancement of the resonance Rayleigh scattering intensity (RRS), and the appearance of new RRS spectra. At the same time, the second-order scattering (SOS) and frequency-doubling scattering (FDS) intensities were also enhanced. The maximum wavelengths were located near 370 nm for RRS, 520 nm for SOS, and 350 nm for FDS, respectively. Among them, the RRS method had the highest sensitivity and the detection limit was 5.60 ng mL−1 for Ralo, and its linear range was 0.05-2.37 μg mL−1. A new RRS method for the determination of trace Ralo using gold nanoparticles probe was developed. The optimum conditions of the reaction and influencing factors were investigated. In addition, the reaction mechanism and the reasons for the enhancement of RRS were discussed.  相似文献   

15.
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   

16.
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   

17.
在pH4.5~7.0的Britton-Robinson(BR)缓冲溶液中,呋塞米(FUR)与Pd(Ⅱ)形成1:1的螯合阴离子,它能进一步与乙基紫(EV)、结晶紫(CV)、甲基绿(MeG)、亮绿(BG)、甲基紫(MV)等碱性三苯甲烷染料(BTPMD)阳离子通过静电引力和疏水作用形成FUR:Pd(II):BTPMD为1:1:1的离子缔合物.此时,该离子缔合反应不仅能引起吸收光谱的变化,而且更能导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)的显著增强,其最大RRS波长分别位于324nm(EV,CV和MV体系)和340nm(BG和MeG体系),最大SOS波长分别位于550nm(EV,CV,BG和MeG体系)和530nm(MV体系),而最大FDS波长均位于392nm附近.在一定条件下三种散射增强(ΔIRRS,ΔISOS和ΔIFDS)均与呋塞米(FUR)的浓度成正比.对不同染料体系,三种方法对FUR的检出限分别在0.3~4.9ng/mL(RRS),3.2~33.1ng/mL(SOS)和9.0~85.7ng/mL(FDS)之间,均可用于痕量FUR的测定.本文研究了三元离子缔合物的形成对吸收,RRS,SOS和FDS光谱特征和强度的影响,考察了适宜的反应条件、影响因素和分析化学性质,并以RRS法为例考察了共存物质的影响.据此提出了一种高灵敏度、简便、快速测定FUR的共振光散射新方法,将其用于片剂、注射液、人血清和尿样中FUR的测定,结果满意.文中还对三元离子缔合物的组成、结构和反应机理进行了讨论.  相似文献   

18.
The interaction between erythrosine (ET) and tetracaine hydrochloride (TA) 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 of Britton-Robinson (BR) buffer solution of pH 4.5, erythrosine reacted with tetracaine hydrochloride to form 1:1 ion-association complex. As a result, the new spectra of RRS, SOS and FDS appeared and their intensities enhanced greatly. The maximum peaks of RRS, SOS and FDS were at 342 nm, 680 nm and 380 nm, respectively. The intensities of the three scattering were directly proportional to the concentration of TA in the range of 0.008-4.2 microg mL(-1) for RRS, 0.027-4.2 microg mL(-1) for SOS and 0.041-4.2 microg mL(-1) for FDS. The methods had very high sensitivities and good selectivities, and the detection limits were 0.003 microg mL(-1) for RRS, 0.008 microg mL(-1) for SOS and 0.012 microg mL(-1) for FDS, respectively. Therefore, a new method was developed to determinate trace amounts of TA. The recovery for the determination of TA in blood serum and urine samples was between 97.0% and 103.8%. In this study, mean polarizability was calculated by AM1 quantum chemistry method. In addition, the reasons for the enhancement of scattering spectra and the energy transfer between absorption, fluorescence and RRS were discussed.  相似文献   

19.
在pH为9.0的Clark-Lubs缓冲溶液中, 强力霉素、土霉素、四环素和金霉素等四环素类抗生素与钨酸钠反应形成1∶1的阴离子螯合物, 它仅能引起吸收光谱的变化, 不能引起共振瑞利散射(RRS)的增强, 但是当该螯合物进一步与乙基紫反应形成三元离子缔合物时, RRS显著增强并产生新的RRS光谱, 它们具有相似的光谱特征, 最大RRS波长均位于328 nm处. 4种抗生素的线性范围和检出限分别为0.047~4.8 μg•mL-1和14.1 ng•mL-1(强力霉素); 0.078~5.0 μg•mL-1和23.5 ng•mL-1(土霉素); 0.081~5.7 μg•mL-1和24.4 ng•mL-1(四环素); 0.122~7.7 μg•mL-1和36.6 ng•mL-1(金霉素). 考察了三元离子缔合配合物的组成, 讨论了配合物的结构和反应机理, 并发展了一种高灵敏、简便快速测定四环素类抗生素的新方法.  相似文献   

20.
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   

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