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1.
茜素红S与人血清白蛋白相互作用的分光光度研究   总被引:32,自引:3,他引:32  
在pH4.3左右的Briton-Robinson(B-R)缓冲溶液中,茜素红S(ARS)与人血清白蛋白(HSA)结合,生成红色的复合物,吸光度值与HSA含量呈线性关系。复合物的吸收峰值λmax为530nm,比ARS试剂本身红移110nm。其表观摩尔吸光系数ε=1.0×104L·mol-1·cm-1。HSA标准曲线在其质量浓度10~900mg/L间呈线性关系,最低检出限为3mg/L。研究了该配合物用于蛋白质分光光度法测定的基本条件。应用该法测定了人血清样品,回收率在96.9%~102.1%范围内。实验表明该反应选择性、重现性和对照性均好,操作简便,适用测定浓度范围宽  相似文献   

2.
The best complexing conditions have been determined for the tin-stilbazo-poly(sulfonylpiperidi nylmethylene hydroxide) system. The ratio between the components in the complex has been found, and the mechanism of complexation has been examined. A rapid procedure for the determination of tin has been developed and tested in the analysis of standard reference samples of bronzes.  相似文献   

3.
研究了氯霉素与茜素红之间的络合反应,确定了最佳反应条件,建立了一种快速、简便测定氯霉素含量的可见分光光度法。研究表明,在pH=11.41的B-R介质中,氯霉素与茜素红在室温条件下即可形成1∶1型络合物,该络合物的λmax=474 nm,表观摩尔吸光系数ε为1.19×104L/(mol.cm)。氯霉素的浓度在2.0×10-7~3.0×10-5mol/L范围内服从比耳定律,相关系数r为0.9985。测定结果的相对标准偏差为0.86%(n=10),回收率为99.4%~101.2%。  相似文献   

4.
In order to understand the chelation process and investigate the intermediate species as a step towards verifying the exact functional groups that are involved in bonding with transition metals, specifically Cu(II) and Zn(II), pH-oscillotitrimetric (pHOT) and volumetric-oscillographic (VOG) methods have been profoundly used. Alizarin Red S (ARS) - as one of the chameleon compounds (chromogenic) - confirms its different approach of bonding with copper and zinc in different mediums. These two methods thoroughly confirm the adequate conditions for each metal to chelate with ARS. pH is responsible for the ambience in which the formation energy in its less value for the salt or complex to be formed, confirming that pH  =  5 is the value that allows Cu(II) to bond with ARS, whereas Zn(II) bonds at pH = 6. A new approach has been also suggested as to how to discuss the titrimetric curves in both methods, taking into account the importance of ‘volumetric-oscillographs’ that give more information when analysed appropriately. Volumetric-oscillographs have been shown and utilized as fingerprint spectrums to track any change in the solutions and firmly expect the compounds that can be step-by-step formed during titration operation. The resulting-in rules have been suggested during reading the graphs. Moreover, the competition between these two metals to chelate with ARS has been extensively studied.  相似文献   

5.
《Analytical letters》2012,45(8):1625-1633
ABSTRACT

Aluminium was determined in a weakly alkaline medium by reaction with alizarin at trace level. Flotation of the complex was carried out with heptane, followed by dissolution in N, N-dimethylformamide (DMF) for subsequent spectrophotometric determination. The molar absorptivity was 2.92×105 mol? cm? at 518 run. Beer's law was obeyed in the range 5–80 μg/1 and the detection limit was 0.4μg/l.

The reliability of the procedure was confirmed by determination of a sample of milk with Graphite Furnace Atomic Absorption Spectrophotometric method (GFAAS). The precision and accuracy of the method were both acceptable via F and tests at the 95% confidence level.  相似文献   

6.
Zhong H  Li N  Zhao F  Li KA 《Talanta》2004,62(1):37-42
A new protein determination method by enhanced Rayleigh light scattering (RLS) technique has been developed. In acid condition (pH=3.60), RLS of 1,2-dihydroxyanthraquinone-3-sulfonate (Alizarin Red S) can be greatly enhanced by addition of proteins, resulting in two characteristic peaks, 360 and 505 nm, respectively. The new protein assay is based on the RLS enhancement and spectrum change. The optimum condition for the reaction was investigated. The linear range is 0.20-24.9 μg ml−1 for BSA and 0.20-15.5 μg ml−1 for HSA. The detection limits (S/N=3) are 9.59 ng ml−1 for BSA and 9.51 ng ml−1 for HSA. The results of determination for human serum samples were comparable to those obtained by Bradford method. The binding stoichiometry was determined.  相似文献   

7.
A new and convenient method for the determination of Alizarin Red S by the perturbations caused by different amounts of Alizarin Red S on a novel B-Z oscillating system is proposed. This new type Belousov-Zhabotinskii involves a macrocyclic copper(II) complex [CuL](ClO4)2 as catalyst and malic acid as the substrate. The ligand L in the complex is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene. It is found that the relationship between the change in the oscillation amplitude and the logarithm of the Alizarin Red S concentration in the range of 1.5 × 10−7 to 1 × 10−3 M fits a polynomial model: ΔA = 659 + 184.2 log [Alizarin Red S]+ 12.9 log2 [Alizarin Red S]. The RSD obtained with ten samples is 4.4%. The probable mechanism involving the perturbation of Alizarin Red S on the oscillating chemical system is also discussed.   相似文献   

8.
《Analytical letters》2012,45(14):2621-2633
Abstract

A sensitive and selective voltammetric method for determination of antimony(III) using Alizarin Red S (ARS) as complexing agent is described. The method is based on the monitoring the oxidation peak of antimony(III)-ARS complex at ?520 mV in ammonium-ammonia buffer (pH = 7.5). The peak current was measured by scanning the potential from ?700 mV versus Ag/AgClto more positive potentials without accumulation in the presence of 1 × 10?6 mol L?1 of ARS. The limit of detection (3 s) and limit of quantification (10 s) of the method were calculated from calibration curve as 1.45 µg L? and 4.8 µg L? respectively. The calibration plot for antimony(III) was linear in the range of 4.8–30 µg L?. The interference of various ions was examined. Serious interference from Al(III), Fe(III), Cu(II), Pb(II), and Zn(II) was eliminated by addition of EDTA to the solution. The method was applied to drinking water samples. The recoveries were in the range 94% – 105%. The results obtained from the developed method were compared with those from the differential-pulse anodic-stripping method and no statistically significant difference was found.  相似文献   

9.
Di J  Yang T 《Talanta》2003,61(2):165-171
A new high sensitive spectrophotometric determination of trace molybdenum was investigated. The sensitivity of the determination of molybdenum, which based on the color charge transfer complex of molybdotungstophosphate-3,3′,5,5′-tetramethylbenzidine, was greatly enhanced by copper(II) ions in the presence of polyvinyl alcohol. The improved method maintained the features of simplicity, rapidity and selectivity, especially eliminating the interference from tungsten. Under the optimum conditions, Beer's law was obeyed over the range from 2 to 32 ng ml−1 molybdenum with molar absorptivity being 4.92×105 l mol−1 cm−1 at 660 nm. The relative standard deviation was 1.2% under nine determinations for 16 ng ml−1 Mo(VI). The present method had been applied to the determination of trace molybdenum in tungsten ores with satisfactory results.  相似文献   

10.
The electrochemical behavior and the interaction of alizarin red S (ARS) with calf thymus DNA was investigated on a bare glassy carbon electrode (GCE) and DNA modified GCE (DNA/GCE), respectively. ARS showed a pair of redox peaks at ?0.445 V and ?0.414 V on a bare GCE. On addition of DNA into the ARS solution, the peak current of ARS decreased and the peak potential positively shifted, but without new redox peaks appeared. The ARS reduction peak current increased with immersion time on a DNA/GCE. The results showed that ARS could interact with DNA molecules by intercalative binding mode. The equilibrium constant, binding number and the ratio of binding constant for oxidized and reduced ARS forms were obtained. The DNA damage was directly detected by appearance of guanosine and adenosine bases oxidation signal. The influence of experimental conditions on DNA damage extent was discussed in detail.  相似文献   

11.
A new modified carbon paste electrode based on multi-walled carbon nanotube and Alizarin Red S acts as a chelating agent for tellurium(IV) ions, is described. The electrochemical responses were found to be analytically suitable to develop a method for the determination of tellurium at low concentration levels. Under optimised operational conditions, the sensor exhibited linear behaviour in the range of 2.0–300 ng mL?1 (correlation coefficient: 0.9982) with a detection limit of 0.45 ng mL?1. The results indicate that the sensor is sensitive and effective for the determination of tellurium in water samples and certified reference materials.  相似文献   

12.
A simple, rapid, sensitive, and inexpensive method for spectrophotometric determination of chromium(VI), based on the absorbance of its complex with 1,4,8,11-tetraazacyclotetradecane (cyclam) is presented. The complex showed a molar absorbtivity of 1.5?×?104?L?mol?1?cm?1 at 379?nm. Under optimum experimental conditions, a pH of 4.5 and 1.960?×?103?mg?L?1 cyclam were selected, and all measurements were performed 10?min after mixing. Major cations and anions did not show any interference; Beer's law was applicable in the concentration range 0.2–20?mg?L?1 with a detection limit of 0.001?mg?L?1. The standard deviation in the determination is ±0.5?mg?L?1 for a 15.0?mg?L?1 solution (n?=?7). The described method provides a simple and reliable means for determination of Cr(VI) in real samples.  相似文献   

13.
茜素红S-铜(Ⅱ)金属配合物与溶菌酶作用研究   总被引:5,自引:0,他引:5  
采用UV-Vis光谱法研究了pH=4.25的缓冲溶液中茜素红S(ARS)-铜(Ⅱ)金属配合物与溶菌酶(LYS)的结合反应。提出了双波长物质的量比法和平衡透析物质的量比法,与单波长物质的量比法进行对照测定研究,实验结果基本相符。研究发现,ARS-Cu(Ⅱ)-LYS的最大吸收波长为526 nm,比ARS红移96 nm,比ARS-Cu(Ⅱ)配合物红移10 nm。在526 nm处,测得ARS-Cu(Ⅱ)-LYS三元配合物的结合比为nARSnCu(Ⅱ)nLYS=6∶3∶1,摩尔吸光系数ε=7.93×104 L·mol-1·cm-1,ARS-Cu(Ⅱ)配合物与LYS作用的条件平衡常数K=3.21×1012。ARS-Cu(Ⅱ)与LYS之间的作用力为配位键和电荷力。  相似文献   

14.
茜素红S与壳聚糖相互作用的电化学行为研究   总被引:3,自引:0,他引:3  
在pH5.0NaAc—HAc缓冲溶液中,茜素红S能与壳聚糖生成一种紫红色的复合物。复合物使茜素红S在-0.408 V处的还原峰峰电流降低。在选定的最佳条件下,用循环伏安法和线性扫描极谱法测定其峰电流的降低值与壳聚糖的浓度在0.5~7.5mg/L的范围内呈线性关系,线性回归方程为△ip^#=30.92 108.4CCTS(mg/L),相关系数0.9990;检出限0.4mg/L。据此建立一种快速、简便测定壳聚糖的方法。该方法可应用于实际样品的测定。  相似文献   

15.
《Analytical letters》2012,45(3):141-152
Abstract

The complex formed between molybdenum(VI) and benzoylacetanilide in the pH range 0.6 and 1.9 has been extracted into methyl isobutyl ketone and the absorbance has been measured at 410 mμ. Quantities of 0.15 to 2.10 mg of molybdenum have been determined with a standard deviation of 0.6%. The color is stable up to 2 hours. The presence of Co2+, Ni2+, Zn2+, Mn2+, Be2+, Al3+, Cr3+, Ce4+, Th4+ or UO2+ 2 up to 100 μg causes no interference. Ordinarily, Fe3+ interferes with the determination, but when masked with 1 ml of 0.5% solution of ascorbic acid the tolerance limit is 10 mg. Thus, molybdenum can be determined in steel when present in amounts as low as 0.26%.  相似文献   

16.
依诺沙星与茜素红在水-乙醇介质中发生电荷转移反应,其中依诺沙星是电子给予体,茜素红是电子接受体,依据此荷移反应建立了一种快速测定依诺沙星的荷移分光光度法.荷移络合物在 546 nm 波长处有最大吸收,表观摩尔吸光率为 8.04×103L·mol-1·cm-1,相关系数为0.999 9.该络合物的组成为 1:1,表观稳定常数为 2.84×104.依诺沙星的质量浓度在 0~40 mg·L-1范围内服从比耳定律.当依诺沙星的质量浓度为 20 mg·L-1时,测定结果的相对标准偏差(n=6)为 1.2%,回收率在 99%以上.测定了依诺沙星制剂中有效成分的含量,与文献[1]方法结果基本吻合.  相似文献   

17.
Sun W  Jiao K 《Talanta》2002,56(6):1073-1080
In this paper, the electrochemical behavior of the interaction of Alizarin Red S (ARS) with bovine serum albumin (BSA) was investigated on the hanging mercury drop electrode (HMDE). In the acidic solution (pH 4.2), ARS can be easily reduced on the HMDE and it has a well-defined polarographic wave at −0.29 V (SCE). On addition of BSA or human serum albumin (HAS) into the ARS solution, the reduction peak current of ARS decreases without the movement of the peak potential and the appearance of new peaks. The study shows that a new electrochemically non-active complex is formed via intercalation of ARS with BSA or HSA, which can not be reduced on the Hg electrode. The decrease of reductive peak current of ARS is proportional to BSA and HSA concentration in the range of 2.0–60 and 2.0–40 mg l−1, respectively. The detection limit of BSA and HSA is 1.0-mg l−1. The analytical results of human serum and urine samples by this method were in good agreement with the Coomassie brilliant blue G-250 assay. The binding number and the binding interaction mechanism are also discussed.  相似文献   

18.
Lubal P  Koprivová H  Sedo O  Havel J  Lis S  But S 《Talanta》2006,69(4):800-806
Spectrophotometric determination of molybdenum(VI) and tungsten(VI) with application of Artificial Neural Networks is proposed and it was applied for elemental analysis of solid polyoxometalates. Better results in comparison with previously those achieved by previous published method were demonstrated. MALDI-TOF Mass Spectrometry was tested for possible determination of molecular weight of polyoxometalates utilizing different matrices. Phenomena observed during desorption-ionisation processes are discussed. LDI-TOF MS was found to be suitable for the determination of Mo:W ratio in polyoxometalates as a rapid screening method to follow synthetic procedure.  相似文献   

19.
茜素红荷移分光光度法测定头孢克洛   总被引:1,自引:0,他引:1  
以茜素红(ARS)为荷移试剂,采用分光光度法直接测定了头孢克洛(CFC),并研究了ARS-CFC络合物的可见光谱性质及最佳反应条件.CFC浓度在1.157~38.58μg/mL范围内遵循比尔定律,回归方程为A=0.1312683 p+0.01064(ρ:μg/mL),检出限0.56μg/mL,表观摩尔吸光系数5.77×...  相似文献   

20.
A new catalytic Spectrophotometric method for the determination of trace amounts of molybdenum (VI) has been proposed. The method is based on the catalytic effect of Mo(VI) on the reduction of metanil yellow by hydrazine dihydrochloride. Under experiment condition, the linear range of determination is 20–160 ng/mL for molybdenum and the detection limit is 11.2ng/mL. The method has been used to determine trace molybdenum in bean samples with the recovery of 96.0–99.0%, with relative standard deviations of 1.50–2.53%.  相似文献   

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