Analysis of electroplating baths by capillary electrophoresis with high voltage contactless conductivity detection

Abstract

A new design of a contactless conductivity detector for capillary electrophoresis is demonstrated for the detection of compounds of relevance in metal plating baths. Galvanic baths for the deposition of Zn, Cu, Ni and Ag were analysed. The compounds related to the zinc plating system contained Zn2+, Na+, Mg2+ and NH4+, the copper plating system CuEDTA2−, SO42−, oxalate−, EDTA2− and glyoxylate, the nickel plating system Ni2+, Co2+ and NH4+ and the silver plating system included AgCN−, NO3− and CN−. Concurrent determinations of the compounds could be carried out in less than 10 min.

New Fully Portable Instrument for the Versatile Determination of Cations and Anions by Capillary Electrophoresis with Contactless Conductivity Detection

“…The resulting current, flowing through the detection cell, is subsequently picked up by another electrode and converted to voltage using an OPA655 (Texas Instruments, 1 MW feedback resistor) operational amplifier located in the cell itself. Details on the construction of the detector cell can be found in reference [20]. The signal is then rectified, amplified, lowpass filtered and offset using the electronic circuitry described in an earlier publication [21].…”

Quantification of plasma lactate concentrations using capillary electrophoresis with contactless conductivity detection

“…The detector was also built in-house. It is based on two electrodes of 4 mm length, consisting of steel tubing with an internal diameter of about 400 mm, and a detection gap of 1 mm [43]. A sine-wave voltage of 320 kHz and an amplitude of 340 Vpp (peak-to-peak) was used for cell excitation.…”

Study of acetylcholinesterase inhibitors using CE with contactless conductivity detection

“…Both instruments were fitted with a contactless conductivity detector constructed in-house. The mechanical and electrical details of the detector cell can be found in previous publications [31,32]. The cell current was transformed into an AC voltage with an operational amplifier (OPA655, Texas Instruments, Dallas, TX, USA) in the current follower configuration (feedback resistor: 220 kO).…”