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1.
Time courses of changes in manganese, iron, copper, and zinc concentrations were examined in regions of the brain of a 6-hydroxydopamine (6-OHDA)-induced rat model of Parkinson’s disease using inductively coupled plasma mass spectrometry (ICP-MS). The concentrations were simultaneously determined in brain section at the level of the substantia nigra 1, 3, 7, 10, 14, and 21 days after the 6-OHDA treatment and compared with those of control rats. The distributions of these elements were obtained for 18 regions of the sagittal section (1-mm thick). The ICP-MS results indicated that Mn, Fe, Cu, and Zn levels of the 6-OHDA-induced parkinsonian brain were observed to increase in all regions that lay along the dopaminergic pathway. In the substantia nigra, the increase in Mn level occurred rapidly from 3 to 7 days and preceded those in the other elements, reaching a plateau in the 6-OHDA brain. Iron and Zn levels increased gradually until 7 days and then increased rapidly from 7 to 10 days. The increase in the copper level was slightly delayed. In other regions, such as the globus pallidus, putamen, and amygdala, the levels of Mn, Fe, Cu, and Zn increased with time after 6-OHDA treatment, although the time courses of their changes were region-specific. These findings contribute to our understanding of the roles of Mn and Fe in the induction of neurological symptoms and progressive loss of dopaminergic neurons in the development of Parkinson’s disease. Manganese may hold the key to disturbing cellular Fe homeostasis and accelerating Fe levels, which play the most important role in the development of Parkinson’s disease.  相似文献   

2.
火焰原子吸收光谱法连续测定菠萝中的铜、锌、铁、锰   总被引:6,自引:0,他引:6  
探讨了用微波消化罐消化样品、以火焰原子吸收光谱法在同一体系中测定菠萝中微量元素铜、锌、铁、锰的方法。考察了硝酸、过氧化氢的不同用量以及消化时间长短的影响和在同一体系中钢、锌、铁、锰的彼此干扰情况。在选定条件下,检测限铜为0.0060μg/mL、锌为0.0074μg/mL、铁为0.0040μg/mL、锰为0.0090μg/mL,相对标准偏差1.9%-4.7%,回收率93.2%-105%。  相似文献   

3.
采用微波消化技术,以氘灯背景校正方式,在HNO3介质中,直接用火焰原子吸收法在同一体系中连续测定了金银花中微量元素Fe、Zn、Cu、Mn,并优化了最佳实验条件.在选定条件下,检出限为Fe 0.0047 μg/mL,Zn 0.0032μg/mL,Cu 0.0052μg/mL,Mn 0.0028μg/mL,相对标准偏差为1.5%~3.2%,回收率为96.4%~103.4%.适用于金银花中微量Fe、Zn、Cu、Mn的测定.  相似文献   

4.
A dynamic ultrasound-assisted extraction procedure utilizing diluted nitric acid was developed for the determination of copper, iron, manganese and zinc in human hair taken from workers in permanent contact with a polluted environment. The extraction unit of the dynamic ultrasound-assisted extraction system contains a minicolumn into which a specified amount of hair (5–50 mg) is placed. Once inserted into the continuous manifold, trace metals were extracted at 3 mL min−1 with 3 mol L−1 nitric acid under the action of ultrasound for 2 min for zinc and 3 min for copper, iron and manganese determination, and using an ultrasonic water-bath temperature of 70 °C for zinc and 80 °C for copper, iron and manganese determination. The system permits the direct analysis of hair and yields concentrations with relative standard deviations of <3% (n = 11). The applicability of the procedure was verified by analysing human hair samples from workers exposed to welding fumes, and its accuracy was assessed through comparison with a conventional sample dissolution procedure and the use of a certified reference material (BCR 397, human hair).  相似文献   

5.
白玲  刘超 《分析试验室》2006,25(9):81-83
痕量Fe^3+、Mn^2+、Cu^2+、Zn^2+与2-(5-溴-2-吡啶偶氮).5-二乙氨基苯酚(5-Br-PADAP)和对.(1,1,3,3.四甲基丁基)苯基醚(Triton X-100)在pH8.3发生高灵敏显色反应,所形成的三元胶束络合物的吸收光谱严重重叠。本文采用主成分-偏最小二乘法(PC—PLS)辅助分光光度法成功地测定了合成试样及饲料中上述4种痕量组分。结果表明,PC—PLS法是化学计量学法中一种可适用于基体较复杂的实际试样中痕量组分同时分光光度测定的优良的多元计算方法。  相似文献   

6.
痕量Fe^3 ,Mn^2 ,Cu^2 ,Zn^2 ,Co^2 ,Ni^2 与2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚(5-Br-PADAP)和溴化十六烷基三甲基铵(CTMAB)在PH8.3时发生高灵敏显色反应,所形成的三元胶束络合的吸收光谱严重重叠,采用偏最小二乘法(PLS)辅助分光光度法测定了合成试样及饲料中上述6种痕量组分,结果表明,PLS法是化学计量学中一种可适用于基体较复杂的实际试样中痕量组分分光度同时测定的多元计算方法。  相似文献   

7.
Mercury vapor is effectively absorbed via inhalation and easily passes through the blood–brain barrier; therefore, mercury poisoning with primarily central nervous system symptoms occurs. Metallothionein (MT) is a cysteine-rich metal-binding protein and plays a protective role in heavy-metal poisoning and it is associated with the metabolism of trace elements. Two MT isoforms, MT-I and MT-II, are expressed coordinately in all mammalian tissues, whereas MT-III is a brain-specific member of the MT family. MT-III binds zinc and copper physiologically and is seemed to have important neurophysiological and neuromodulatory functions. The MT functions and metal components of MTs in the brain after mercury vapor exposure are of much interest; however, until now they have not been fully examined. In this study, the influences of the lack of MT-I and MT-II on mercury accumulation in the brain and the changes of zinc and copper concentrations and metal components of MTs were examined after mercury vapor exposure by using MT-I, II null mice and 129/Sv (wild-type) mice as experimental animals. MT-I, II null mice and wild-type mice were exposed to mercury vapor or an air stream for 2 h and were killed 24 h later. The brain was dissected into the cerebral cortex, the cerebellum, and the hippocampus. The concentrations of mercury in each brain section were determined by cold vapor atomic absorption spectrometry. The concentrations of mercury, copper, and zinc in each brain section were determined by inductively coupled plasma mass spectrometry (ICP-MS). The mercury accumulated in brains after mercury vapor exposure for MT-I, II null mice and wild-type mice. The mercury levels of MT-I, II null mice in each brain section were significantly higher than those of wild-type mice after mercury vapor exposure. A significant change of zinc concentrations with the following mercury vapor exposure for MT-I, II null mice was observed only in the cerebellum analyzed by two-way analysis of variance. As for zinc, the copper concentrations only changed significantly in the cerebellum. Metal components of metal-binding proteins of soluble fractions in the brain sections were analyzed by size-exclusion high-performance liquid chromatography (HPLC) connected with ICP-MS. From the results of HPLC/ICP-MS analyses, it was concluded that the mercury components of MT-III and high molecular weight metal-binding proteins in the cerebellum of MT-I, II null mice were much higher than those of wild-type mice. It was suggested that MT-III is associated with the storage of mercury in conditions lacking MT-I, and MT-II. It was also suggested that the physiological role of MT-III and some kind of high molecular weight proteins might be impaired by exposure to mercury vapor and lack of MT-I and MT-II.  相似文献   

8.
铁、锰、锌、铜的快速分析常用原子吸收光度法、发射光谱法、等离子体法、电位溶出法等。本文则研究了快速分光光度法,提出了新的分析方法及若干试验研究结果。  相似文献   

9.
应用灵敏极谱波技术测定了健康人及各种癌症患者的发锰、铁、锌、铜,对结果进行了统计分析与评价。  相似文献   

10.
火焰原子吸收光谱法测定奶类食品中铜锌铁锰   总被引:8,自引:0,他引:8  
对火焰原子吸收光谱法(FAAS)测定乳品中铜、锌、铁、锰的条件进行了试验和优化。对方法的干扰因素,准确度和精密度也作了试验。乳品试样用HNO3-HClO4混合酸消化处理。所得溶液蒸发至近干,用稀硝酸(1 99)溶解盐类,溶液经定容后供作FAAS测定。对4元素的测定时,吸光度与浓度之间呈良好线性关系,所求得的线性回归方程及其相关系数可作佐证。应用所提出的方法测定了3种不同的乳制品中的铜、锌、铁及锰,测定值的RSD值均小于3.5%,回收率在93.0%~103.0%之间。  相似文献   

11.
A sensitive and selective method for the simultaneous determination of copper, zinc and lead is presented. The method is based on the adsorptive accumulation of 2′,3,4′,5,7-pentahydroxyflavone (Morin) complexes of these elements onto a hanging mercury drop electrode, followed by reduction of adsorbed species by voltammetric scan using differential pulse modulation. Optimal analytical conditions were found to be Morin concentration of 2.0 μM, pH of 4.0, and an adsorption potential at −500 mV versus Ag/AgCl. With an accumulation time of 60 s, the peak currents are proportional to the concentration of copper, lead and zinc over the 1 to 60, 0.3-80 and 1-70 ng ml−1 range with detection limits of 0.06, 0.08 and 0.06 ng ml−1, respectively. The procedure was applied to the simultaneous determination of copper, lead and zinc in some real and synthetic artificial real samples with satisfactory results.  相似文献   

12.
The syntheses, spectroscopic and electrochemical properties of manganese (3), nickel (4) and iron (5) phthalocyanine complexes, octa-substituted at the peripheral positions with diethlyaminoethanethiol substituent, are reported. The electrochemistry of these complexes and the corresponding cobalt complex (6) are reported. Complex 3 showed two reversible reduction couples attributed to the MnIIIPc2/MnIIPc2 (E½ = −0.12 V versus Ag|AgCl) and MnIIPc2/MnIIPc3 (E½ = −0.82 V versus Ag|AgCl) species. Two ring-based reduction couples were also observed for complex 4. Two reduction couples, assigned to the FeIIPc2/FeIPc2 (E½ = −0.35 V versus Ag|AgCl) and FeIPc2/FeIPc3 (E½ = −0.96 V versus Ag|AgCl) species, and an oxidation couple, attributed to FeIIIPc2/FeIIPc2 (E½ = 0.26 V versus Ag|AgCl) species, were observed. For complex 6, two reductions and one oxidation were also observed with the potential range of 1.2 to −1.8 V versus Ag|AgCl Spectroelectrochemical studies were used to confirm some of the assigned processes.  相似文献   

13.
Reduction of 2-cyanopyridine by sodium in the presence of 3-piperidylthiosemicarbazide produces 2-pyridineformamide 3-piperidylthiosemicarbazone, HAmpip. Complexes with iron(III), cobalt(II,III) copper(II) and zinc(II) have been prepared and characterized by molar conductivities, magnetic susceptibilities and spectroscopic techniques. In addition, the crystal structures of HAmpip, [Fe(Ampip)2]ClO4, [Cu(HAmpip)Cl2]·CH3OH and [Zn(HAmpip)Br2]·C2H6SO have been determined. Coordination is via the pyridyl nitrogen, imine nitrogen and thiolato or thione sulfur when coordinating as the anionic or neutral ligand, respectively.  相似文献   

14.
单扫描示波极谱法连测五味子、榛蘑中的铜和锌   总被引:1,自引:0,他引:1  
研究了在HCl-KSCN底液中用单扫描示波极谱法连续测定五味子、榛蘑中铜和锌的方法。在此底液中,铜、锌分别在-0.42V(vs.SCE)、-1.03V(vs.SCE)处产生一敏锐的二阶导数波,检出限分别为0.005、0.01μg/mL,线性范围分别为0.01~8.00μg/mL,0.01~10.00μg/mL。应用本方法测定了五味子、榛蘑中的铜和锌,方法回收率为96.5%~101.8%。  相似文献   

15.
Polarographic adsorptive complex waves in the presence of catechol violet were studied for the simple and rapid simultaneous determination of traces of zinc, lead and copper in human hair and UV irradiation techniques were compared with conventional acid digestion procedures. UV irradiation of acidified hair with a 500-W mercury are lamp releases bound zinc, lead and copper after 3 h. Compared with the acid digestion procedure, the blank of the UV irradiation method is lower, the amounts of reagents used are smaller and the sample manipulations are simpler. The mechanisms of the polarographic adsorptive complex waves of Zn-, Pb-Cu- catechol violet are discussed.  相似文献   

16.
In the present work, a slurry sampling flame atomic absorption spectrometric method to determine directly manganese and zinc in powdered chocolate samples is proposed. The optimization step was performed using univariate methodology involving the following factors: nature and concentration of the acid solution, sonication time, and particle size. The established conditions led to the use of a sample mass of 150 mg, 2.0 mol L− 1 nitric acid solution, sonication time of 15 min, and a slurry volume of 50 mL. This method allows the determination of manganese and zinc with detection limit of 52 and 61 ng g− 1, respectively, and a precision expressed as relative standard deviation (RSD) of 2.6% and 3.2% (both, n = 10) for contents of manganese and zinc of 52.4 and 100.0 μg g− 1, respectively. The proposed method was applied for determination of manganese and zinc in five powdered chocolate samples. In these, the manganese content varied from 42.8 to 52.7 and from 88.6 to 102.4 μg g− 1 of zinc. The analytical results were compared with the results obtained by analysis of these samples after digestion using open vessel and acid bomb digestion procedures and determination using FS-FAAS. The statistical comparison by t-test (95% confidence level) showed no significant difference between these results.  相似文献   

17.
An efficient and convenient bimetallic MnF2/CuI catalyst in combination with trans-1,2-diaminocyclohexane has been developed for the cross-coupling of nitrogen heterocycles with aryl halides in water at moderate temperature. A variety of nitrogen nucleophiles including pyrazole, 7-azaindole, indazole, indole, pyrrole and imidazole afforded the corresponding products in moderate to good yields (up to 94%) under the described arylation conditions.  相似文献   

18.
19.
20.
ICP-AES法测定滑子蘑中的Cd、Cu、Pb和Zn   总被引:2,自引:0,他引:2  
周淼  徐烨  迂君  薛峰 《分析试验室》2008,27(6):101-104
建立了采用V(HNO3)∶V(HClO4)=15∶2作消解液进行溶样,ICP-AES法同时测定滑子蘑中Cd、Cu、Pb、Zn的分析方法,进行了ICP工作参数的优化,消解条件的选择及消解结果精密度实验。在最佳测定条件下,4种元素标准曲线相关性好(r为0.9990~0.9995),线性范围宽,精密度RSD为0.4%~4.6%,样品加标回收率为91.0%~101.0%,已用于实际样品的测定。  相似文献   

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