A novel method for the determination of vitamin C（Vc） is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-orde...A novel method for the determination of vitamin C（Vc） is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-order derivative spectrum were obtained from the original spectrum. The values of derivative selected at 995 nm were used for determination. It was proved that Vc could quickly react with Folin-Ciocalteau reagent within 5 min and the product was quite stable for a long time. The conditions required for this method is not very complicated, its precision and accuracy are similar to those of the iodometric titration described in Chinese Pharmacopoeia, and the limit of detection is 0.312 μg/mL. The determination of the results of vitamin C tablet, pill, and injection demonstrates that this method has wide pharmaceutical applications.展开更多
A quasi-reversible reduction peak of a fentanyl derivative DNPME is found by cyclic voltammetry at Hg electrode. E_(pc)=-1.58 V (vs. Ag/AgCl). The cathodic peak shows adsorptive characteristics. The adsorbed species i...A quasi-reversible reduction peak of a fentanyl derivative DNPME is found by cyclic voltammetry at Hg electrode. E_(pc)=-1.58 V (vs. Ag/AgCl). The cathodic peak shows adsorptive characteristics. The adsorbed species is DNPME neutral molecule. The method for measuring trace amount of DNPME by adsorptive stripping voltammetry is established.展开更多
Novel ferrocenyl derivatives of p-(10-mercaptodecyloxy) benzal 4-ferrocenylaniline have been prepared and characterized by element analysis, 1HNMR, and FAB-MS. Cyclic voltammetry has been used to characterize the self...Novel ferrocenyl derivatives of p-(10-mercaptodecyloxy) benzal 4-ferrocenylaniline have been prepared and characterized by element analysis, 1HNMR, and FAB-MS. Cyclic voltammetry has been used to characterize the self-assembled monolayers formed from the compounds on the gold electrodes.展开更多
A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H2ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H2O had been synthesized and structurally characterized by X...A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H2ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H2O had been synthesized and structurally characterized by X-ray single crystal diffraction in this paper. The Mn(Ⅱ) ion is coordinated with a distorted octahedron by two oxygen atoms from neighboring two deprotonated ligands ADTZ2- and other four oxygen atoms from four coordinated water molecules. The structural feature of the title compound is the formation of one-dimensional manganese chains polymer through the bridging of dioxygen O-O units. In the solid state structure of the complex, one-dimensional manganese chains are joined together by the weak intermolecular hydrogen bonds and vander Waals interactions forming a two-dimensional supramolecular compound. Furthermore, the UV spectra and electro-chemical properties of the title compound were also investigated. CCDC: 260532.展开更多
This paper reported the behavior of cyclic voltammetry (CV), differential pulsevoltammetry (DPV ) and spectroelectrochemistry (SEC) of Co2Co2-superoxide dismutase.The results obtained by CV and DPV were in agreement w...This paper reported the behavior of cyclic voltammetry (CV), differential pulsevoltammetry (DPV ) and spectroelectrochemistry (SEC) of Co2Co2-superoxide dismutase.The results obtained by CV and DPV were in agreement well with that obtained by SEC.The diffusion coefficient, the apparent number of electrons and oxidation-reductionpotentials were obtained.展开更多
制备了壳聚糖/乙炔黑复合修饰电极（CS-AB/GCE）,采用SEM和交流阻抗法对其进行表征。并利用循环伏安法（CV）研究了萘酚异构体（α-N和β-N）在该修饰电极上的电化学行为,对实验条件进行了优化。结果表明,在p H 7.0的PBS缓冲液中,α-N和...制备了壳聚糖/乙炔黑复合修饰电极（CS-AB/GCE）,采用SEM和交流阻抗法对其进行表征。并利用循环伏安法（CV）研究了萘酚异构体（α-N和β-N）在该修饰电极上的电化学行为,对实验条件进行了优化。结果表明,在p H 7.0的PBS缓冲液中,α-N和β-N在该修饰电极上均出现一不可逆氧化峰,且在20-200m V/s范围内,其峰电流与扫速呈线性关系,表明电极过程是受吸附控制的不可逆过程。计算了电极过程的部分动力学参数,优化了差分脉冲伏安法（DPV）的实验参数,并对α-N和β-N进行同时测定,发现二者的微分氧化峰电流值与其浓度在2.5×10-6-1.0×10-4mol/L范围内呈良好的线性关系（rα-N=0.996;rβ-N=0.998）。α-N和β-N的检出限（S/N=3）分别为3.4×10-7mol/L和2.4×10-7mol/L。采用该法对实际水样进行检测,得到α-N和β-N的加标回收率分别为96.7%-105.1%和98.8%-103.9%。展开更多
基金Natural Science Foundation of Jilin Province, China(No.200305502)
文摘A novel method for the determination of vitamin C（Vc） is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-order derivative spectrum were obtained from the original spectrum. The values of derivative selected at 995 nm were used for determination. It was proved that Vc could quickly react with Folin-Ciocalteau reagent within 5 min and the product was quite stable for a long time. The conditions required for this method is not very complicated, its precision and accuracy are similar to those of the iodometric titration described in Chinese Pharmacopoeia, and the limit of detection is 0.312 μg/mL. The determination of the results of vitamin C tablet, pill, and injection demonstrates that this method has wide pharmaceutical applications.
基金This work was supported by the National Natural Science Foundation of China
文摘A quasi-reversible reduction peak of a fentanyl derivative DNPME is found by cyclic voltammetry at Hg electrode. E_(pc)=-1.58 V (vs. Ag/AgCl). The cathodic peak shows adsorptive characteristics. The adsorbed species is DNPME neutral molecule. The method for measuring trace amount of DNPME by adsorptive stripping voltammetry is established.
文摘Novel ferrocenyl derivatives of p-(10-mercaptodecyloxy) benzal 4-ferrocenylaniline have been prepared and characterized by element analysis, 1HNMR, and FAB-MS. Cyclic voltammetry has been used to characterize the self-assembled monolayers formed from the compounds on the gold electrodes.
文摘A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H2ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H2O had been synthesized and structurally characterized by X-ray single crystal diffraction in this paper. The Mn(Ⅱ) ion is coordinated with a distorted octahedron by two oxygen atoms from neighboring two deprotonated ligands ADTZ2- and other four oxygen atoms from four coordinated water molecules. The structural feature of the title compound is the formation of one-dimensional manganese chains polymer through the bridging of dioxygen O-O units. In the solid state structure of the complex, one-dimensional manganese chains are joined together by the weak intermolecular hydrogen bonds and vander Waals interactions forming a two-dimensional supramolecular compound. Furthermore, the UV spectra and electro-chemical properties of the title compound were also investigated. CCDC: 260532.
文摘This paper reported the behavior of cyclic voltammetry (CV), differential pulsevoltammetry (DPV ) and spectroelectrochemistry (SEC) of Co2Co2-superoxide dismutase.The results obtained by CV and DPV were in agreement well with that obtained by SEC.The diffusion coefficient, the apparent number of electrons and oxidation-reductionpotentials were obtained.
文摘制备了壳聚糖/乙炔黑复合修饰电极（CS-AB/GCE）,采用SEM和交流阻抗法对其进行表征。并利用循环伏安法（CV）研究了萘酚异构体（α-N和β-N）在该修饰电极上的电化学行为,对实验条件进行了优化。结果表明,在p H 7.0的PBS缓冲液中,α-N和β-N在该修饰电极上均出现一不可逆氧化峰,且在20-200m V/s范围内,其峰电流与扫速呈线性关系,表明电极过程是受吸附控制的不可逆过程。计算了电极过程的部分动力学参数,优化了差分脉冲伏安法（DPV）的实验参数,并对α-N和β-N进行同时测定,发现二者的微分氧化峰电流值与其浓度在2.5×10-6-1.0×10-4mol/L范围内呈良好的线性关系（rα-N=0.996;rβ-N=0.998）。α-N和β-N的检出限（S/N=3）分别为3.4×10-7mol/L和2.4×10-7mol/L。采用该法对实际水样进行检测,得到α-N和β-N的加标回收率分别为96.7%-105.1%和98.8%-103.9%。
