On-chip capacitively coupled contactless conductivity detection using “injected” metal electrodes†
Abstract
We demonstrate the use of injected gallium electrodes for capacitively coupled contactless conductivity detection (C4D) within a microchip electrophoresis device. Evaluation of the electrodes for quantitative detection of electrophoretically separated lithium, sodium and potassium ions showed the system offers competitive detection limits of 6.1 × 10−6 M, 6.7 × 10−6 M and 8.5 × 10−6 M, respectively. The fabrication process is fast, highly reproducible, and eliminates difficulties with