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1.
This paper reports the electrochemical properties of sulpiride at a mercury electrode,especially its adsorptive characteristic,Sulpiride dissolved in a supporting electrolyte of a McIlvaine buffer at pH 6.8 represents a sensitive and well defined reduction wave by linear sweep stripping voltammetry.This method is based on the pre-concentration and the reduction of sulpiride at a hung mercury drop electrode.The reduction peak potential is -1.72V(vs.Ag-AgCl) and the peak current is proportional to the concentration of sulpiride in the range of 0.1-0.6 μg/mL.The detection limit is 0.0250μg/mL obtained under the experimental conditions selected in this work.The electrochemical properties of this system were investigated.and the proposed method was applied to the determination of sulpiride in pharmaceutical tablets with satisfactory results,It was compared well with the UV spectrophotometric method,showing a superior sensitivity.  相似文献   

2.
用线扫溶出伏安法和循环伏安法研究了鸟嘌呤在玻碳电极上的电化学行为,鸟嘌呤的阳极锋电流与其浓度在1×10-7-5×10-4mol/L范围内有良好线性关系。讨论了实验条件,建立了测定鸟嘌呤的新分析方法,应用于生物样品中鸟嘌呤的测定,结果满意.  相似文献   

3.
《Analytical letters》2012,45(9):1967-1977
Abstract

Organophosphorus pesticides, such as parathion methyl (PTM), fenitrothion (FT), parathion (PT), and isocarbophos (ICP), have sensitive but overlapped voltammetric peaks with peak potentials ?309, ?364, ?317, and ?480 mV, respectively, in Britton‐Robinson buffer of pH 4.8 by application of linear sweep stripping voltammetry (LSSV). In this work, two multivariate calibration methods, partial least squares (both PLS‐1 and PLS‐2), and principal component regression (PCR), were applied to quantitatively resolve the overlapping voltammogram of the mixtures of these four pesticides. The prediction results obtained from a set of independent test samples showed that PLS‐1 method performed better prediction ability than PLS‐2 and PCR methods. The proposed method was successfully applied to the determination of these four pesticides in grain samples after a pre‐extraction step with a solvent of acetone.  相似文献   

4.
Phoxim, benzoyl cyanide-O-(diethoxyphosphinothioyl)oxime, is an organophosphorusinsecticide of moderate to low mammalian toxicity. Phoxim was individuallydetermined in fruit and vegetable samples, utilizing chromatography1 and single sweeppolarography2.Ex…  相似文献   

5.
A new sensitive electrochemical assay of free sulfite in wine samples at a bare glassy carbon electrode is reported. The method is based on the titration of sulfite with Ellman's reagent using voltammetric detection of the final point. The electrochemical sensing protocol should facilitate rapid field screening of sulfite preservatives.  相似文献   

6.
本研究利用含参数积分的导数运算,Reimann-Stielties积分展开,推导了固态平面电极下的线性扫描平行催化伏安法的电流理论方程。所得方程直观明了,各种参数之间的关系较清晰,为无限加和形式,可以精确计算任何kf值的电流理论值,整个过程仅需个人计算机即可完成。  相似文献   

7.
线性扫描伏安法同时测定铬、镉、铜   总被引:9,自引:0,他引:9  
在苯胲类试剂-乙醇-醋酸铵体系中,Cr(Ⅵ)、Cd^2 、Cu^2 都能产生灵敏的阴极络合吸附波。Cr(Ⅵ)的二次导数峰电位在-0.92V(vs.SCE)处,在0.0017~0.67μg/mL范围内与峰电流成正比;Cu^2 的峰电位在-0.21V(vs.SCE)处,在0.0083~5.8μg/mL范围内与峰电流成正比;Cd^2 的峰电位在-0.70V(vs.SCE)处,线性范围为0.0017~0.117μg/mL。这一方法为工业废水中重金属的同时测定提供了可靠、灵敏的检测方法。  相似文献   

8.
吸附溶出伏安法测定普罗帕酮的研究   总被引:1,自引:0,他引:1  
在pH 6.47的磷酸盐缓冲溶液中,可得到普罗帕酮的吸附溶出峰。峰电位为-1.38V(vs.Ag/AgCl),富集1min,溶出峰电流与普罗帕酮浓度在8.0x10~(-9)~7.0x10~(-7)mol/L范围内呈线性关系。富集4min检测下限为3.0×10(-10)mol/L。该法用于测定普罗帕酮制剂及人血清中的痕量普罗帕酮,均得到了满意的结果,并探讨了电极反应过程机理。  相似文献   

9.
Introduction Sensitive linear sweep voltammetry to have been applied to the catalytic kinetic analysis may be helpful for the application of some organic reagents to the analysis of inorganic ones by voltammetry, The catalytic reaction-linear sweep voltammetric method for the determination of noble metals, such as Ag, Os, Ru and Ir has been developed, but no report about the method for the determination of rhodium has been published so far.  相似文献   

10.
《Analytical letters》2012,45(6):1203-1210
ABSTRACT

An electrochemical method using linear sweep voltammetry techniques was developed to determine nitrite ion in aqueous solution in the presence of nitrate. Nitrite solutions exhibited a well-defined oxidation wave at +1.0V vs SCE at vitreous carbon, while no oxidation process was observed for nitrate solutions. The pH of the nitrite solutions varied from 2.37 to 5.60 and no change was observed in the Ep values, except for the pH 5.60 solution, where little change was verified. The potential also did not vary with change in the nitrite concentration in the 5.0 x 10?5 to 7.0 x 10?4 mol L?1 range. Very good straight lines for plots of current versus nitrite concentration in the 7.0 x 10?5 to 7.0 x 10?4 mol L?1 range were obtained; the correlation coefficient was never worse than 0.990. The nitrite determination was also performed in the presence of 1.0 x 10?3 mol L?1 of NO3 ? ions. The addition of NO3 ? did not change significantly the current values even when it was added in one hundred times molar excess.  相似文献   

11.
吸附溶出伏安法测定苯胺的研究   总被引:7,自引:2,他引:7  
在酸性介质中,苯胺与亚硝酸根离子和盐酸萘乙二胺反应生成玫瑰红色偶氮染料,该染料在汞电极上具有良好的吸附性能,并且在氨性缓冲介质中可在汞电极上还原,于-0.55V左右产生一灵敏的吸附极谱波。据此,建立了吸附溶出伏安法测定苯胺的方法。当吸附富集时间为3min时,该法的检测下限为5×10-9mol/L,比分光光度法降低了近两个数量级。应用本方法测定了废水中的苯胺,结果满意。  相似文献   

12.
在0.01mol/LNH.H2O-NH4Cl和3.0×10^-5mol/L安息香缩氨基硫脲体系中,钴产生一灵敏的还原波,其峰电位是-0.94V(vs.SCE),峰电流与钴的浓度在2.0×10-8-1.0×10^-6mol/L范围内成直线关系,检测限为5.0×10^-9mol/L,该法测定水中痕量钴结果令人满意。  相似文献   

13.
A new quantitative method for the determination of DNA in aqueous solution based on the interaction of methyl violet (MV) with fsDNA by linear sweep voltammetric technique is proposed in this paper. The interaction of MV with fsDNA caused the decrease of the reductive peak current of MV at ?0.650 V (vs. SCE) on a mercury electrode in pH 1.5 Britton‐Robinson (B‐R) buffer solution. Factors including the acidity of the buffer, the reaction time, the optimal concentration of MV, the reaction temperature, the influences of the foreign substances, etc. were all carefully investigated. Under the optimal conditions, the decrease of the reductive peak current of MV was proportional to the concentration of fsDNA in the linear range of 0.90~20.0 mg/L and the detection limit for fsDNA was 0.25 mg/L with the RSD of 4.00%. Synthetic samples were determined with satisfactorily results. The stoichiometry of MV with DNA was calculated by voltammetric data and the results showed that the binding ratio of DNA:MV was 1:2 with the binding constant β as 7.36 × 108.  相似文献   

14.
用微分脉冲阴极吸附溶出伏安法测定了利多卡因针剂的含量。浓度与波高的线性范围为1×10~(-7)~3×10~(-4)mol/dm~3。最低检测限l×10~(-8)mol/dm~3。回收率98.07±0.05%。  相似文献   

15.
《Electroanalysis》2003,15(1):27-32
The method of ytterbium(III) trace concentration in the presence of 2‐thenoyltrifluoroacetone (TTA) and polyethyleneglycol (PEG) in ammonium chloride is described. The adsorption was performed at the HMDE at ?1.0 V using linear scan voltammetry and square‐wave voltammetry. The relationship between properties of the SW response of the mixed ligand complex and parameters of a charge transfer were analyzed using theoretical data of SW redox processes.  相似文献   

16.
利用吸附溶出伏安法、极谱催化法测定痕量锗已有报道。但将吸附溶出伏安法与极谱催化法结合进行测定,尚未见报道。我们选择适当的体系和配位体3,4-二羟基苯甲醛(DHB)及氧化剂钒(V),首先使Ge(Ⅳ)-DHB络合物在悬汞电极上于一定电位处吸附富集一定时间,然后电位向负的方向扫描。当达到Ge(Ⅳ)-DHB络合物的还原电位时,Ge(Ⅳ)还原  相似文献   

17.
本文推导了超微带电极上准稳态过程可逆波及其微分、半微分伏安曲线方程式,对曲线的性质进行了详细的讨论。在K4Fe(CN)6·KCl体系中用超微金带电极对理论进行了验证,结果表明,理论与实验相符。  相似文献   

18.
 A sensitive method for the determination of amitraz pesticide at nanomolar level by adsorptive stripping voltammetry at a hanging mercury drop electrode is described. The cyclic voltammograms demonstrate the adsorption of this compound on the mercury electrode. A systematic study of the various experimental parameters, that affect the stripping response, was carried out by differential pulse voltammetry. Using an accumulation potential of −0.50 V, and 30 s accumulation time, the limit of detection was found to be 2.3 × 10−9 mol L−1 and the relative standard deviations (n = 5) was 2.2% at concentration level of 5.0 × 10−8 mol L−1 of amitraz. The influence of diverse ions and some other pesticides was investigated. Finally, the method was applied to the determination of amitraz in spiked soil and water. The relative standard deviation is 4.5% for 5 determinations of amitraz in water and 3.2% for 5 determinations in soil. Received December 6, 2000. Revision March 1, 2001.  相似文献   

19.
微分脉冲吸附溶出伏安法测定苯胺的研究   总被引:4,自引:0,他引:4  
苯胺经重氮化、偶合反应定量生成的偶氮化合物具有很强的电活性。作者用微分脉冲吸附溶出伏安法测定偶氮化合物来定量分析苯胺的含量。以NH3·H2O-NH4Cl(pH=10)缓冲液为底液,富集电位为-015V,富集时间120s,电位扫描速度4mV/s,在-0670V处产生一个灵敏度高、峰形好的溶出峰。苯胺浓度在10-9~10-7mol/L时与峰电流成线性关系。用印染厂土壤、废水和广州垃圾填埋场的渗出液作标准回收试验,平均回收率分别为982%、970%、975%,测定的相对标准偏差为43%、40%、33%。  相似文献   

20.
本文提出了利用吸附溶出催化伏安法测定人参中锗的方法。最佳体系为:2.5×10~(-2)mol/LH_2O_2、2.0×10~(-2)mol/L邻苯二酚、2.0×10~(-3)mol/L H_2SO_4。线性范围为2.0×10~(-9)~2.0×10~(-7)mol/L。当富集时间为4 min时,最低检测浓度为4.0×10~(-10)mol/L。此法己成功地应用于测定人参中的锗。  相似文献   

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