/ Electrode Response / Enzyme Electrodes / Enzyme Layer / enzyme-based detection / Field Effect Transistor / Flame photometer / Glass Electrode / Internal Electrolyte / Iodide Electrode / ion activity / Ion Selective Electrode Measurements / Ion Selective Fluoride Electrode / laboratory instrumentation / Membrane Probe / Osmotic Strength / potentiometric analysis / Primary Ion / Reaction Kinetic Parameters / Relative Standard Deviation / SCIENCE / Chemistry / Analytic / Thin Film Solutions / Uncoated Electrode