Beckman coulter gel filled combination electrodes provide which

beckman-coulter-gel-filled-combination-electrodes-provide-which

Beckman coulter gel filled combination electrodes provide which of the following features to overcome various problems that occur in gel filled electrodes?

A. Filters

B. Semi-permeable membrane

C. Gas-permeable membrane

D. Micro-pore junction

This question was addressed to me during an interview for a job.

The doubt is from Combination Electrode in division pH Meters and Ion Analysers of Analytical Instrumentation

Correct choice is D. Micro-pore junction

The explanation is: Beckman coulter gel filled combination electrode provides a special micro-pore junction to overcome various problems that occur in gel filled electrodes. Here, there is direct contact between the sample and the gel.