Techniques for sensing chloride ions in wet or dry media

A sensor for measuring chloride ion concentration in a medium, comprising:

• a pair of electrodes;
• and
• a polymer film imprinted for uptake of chloride ions under alkaline conditions,
• wherein the polymer film comprises one of
• (i) polypyrrole and polystyrene sulfonate, and
• (ii) poly-methylpyrrole,
• wherein the film is disposed on an electrode of the pair of electrodes for contact with the medium,
• wherein the film is disposed in contact with the pair of electrodes.

A sensor for measuring chloride ion concentration in a medium, comprising:

• a pair of electrodes;
• and
• a polymer film imprinted for uptake of chloride ions under alkaline conditions,
• wherein the film is disposed on an electrode of the pair of electrodes for contact with the medium,
• wherein the film is disposed in contact with the pair of electrodes, and
• wherein the pair of electrodes comprises gold electrodes.

A sensor for measuring chloride ion concentration in a medium, comprising:

• a pair of electrodes;
• and
• a conductive polymer film imprinted for uptake of chloride ions under alkaline conditions,
• wherein
• the polymer film comprises one of
• (i) methylpyrrole,
• (ii) polypyrrole and polystyrene sulfonate, and
• (iii) poly-methylpyrrole,
• the film is disposed in contact with the pair of electrodes,
• the film is disposed for contact with the medium, and
• an electrical conductivity of the film depends on an amount of chloride ions taken up by the film.

An apparatus for long term monitoring of chloride ion concentration in a medium, comprising:

• a sensor platform for embedding in a medium;
• a transmitter disposed on the sensor platform for transmitting to an interrogation unit a response signal based on a chloride measurement;
• and
• a chloride sensor disposed on the sensor platform, which chloride sensor generates the chloride measurement, said chloride sensor comprising
• a pair of electrodes, and
• a conductive polymer film imprinted for uptake of chloride ions under alkaline conditions,
• wherein
• the film is disposed in contact with the pair of electrodes,
• the film is disposed for contact with the medium, and
• an electrical conductivity of the film depends on an amount of chloride ions taken up by the film.