Sweat chloride analysis can be quantified by which two methods?

• A. Coulometry, Amperometry
• B. Titration, Potentiometry
• C. Spectrophotometry, Chromatography
• D. Electrogravimetric, Gravimetric

Answer: (A)

Sweat chloride analysis is effectively done with electrochemical methods that turn the amount of chloride into an electrical signal. In coulometry, a constant current is applied to drive a reaction that consumes chloride completely; by measuring the total charge passed, you can relate that charge directly to the number of chloride ions present through Faraday’s law. This makes the result highly precise and well-suited for small, challenging samples like sweat.

Amperometry uses a fixed potential where the chloride-related redox reaction at the electrode produces a current. The magnitude of that current, or the integrated current over time, is proportional to the concentration of chloride in the sample. This approach is fast, sensitive, and compatible with automated instrumentation used in clinical labs.

Other methods listed, such as titration, spectrophotometry, chromatography, or gravimetric techniques, are not as practical or reliable for sweat chloride in routine analysis. Titrations require clear endpoints and can be affected by the sweat matrix; spectrophotometry and chromatography add unnecessary complexity for a straightforward ionic measurement; gravimetric methods are less feasible for trace ions in a small, complex fluid like sweat.

So, the best-fit pair for quantifying sweat chloride are electrochemical approaches that translate ion content directly into electrical signals: coulometry and amperometry.