Bestimmung von Jod in schwer aufschließbaren (getrockneten) biologischen Substanzen

Amperometric determination of sulfide at a pre-oxidised nickel electrode in acidic media

“…[27][28][29] The resulting absorbance spectra of the solutions in which a voltammetric experiment had been undertaken confirms the presence of Ni 2+ by an enhancement in the absorbance spectra at 460 nm. [27][28][29] In order to provide quantitative evidence for the formation of Ni 2+ the sample was doped with 4 mM Ni 2+ and the resulting spectra of this solution reveals once again an enhancement in the absorbance at 460 nm. Analysis of the absorbance at 460 nm reveals the presence of 1.5 mM Ni 2+ (Fig.…”

“…In order to provide evidence that nickel ions were being liberated from the electrode surface after the electrochemical experiments with sulfide had been completed, a standard UV/ Vis protocol based on the use of dimethylglyoxime was undertaken. [27][28][29] Nickel standards solutions (2 to 10 mM) for a calibration plot were prepared from a stock solution of 4 mM nickel sulfate salt dissolved in deionised water. An addition of 4 mM dimethylglyoxime to the nickel standards and to the sample were made from a 50 mM dimethylglyoxime stock solution in ethanol.…”