In immunoassay instrumentation, which pairing correctly matches the detector type with the instrument commonly used to read it?

• A. IFA - Fluorometer
• B. Chemiluminescence - Luminometer
• C. Radioassay - Scintillator
• D. Turbidimetry - Nephelometer

Answer: (A)

The detector type in immunoassay readouts is tied to how the signal is produced. Immunofluorescence uses fluorescent labels that emit light when excited, so a fluorometer—the instrument designed to excite and quantify fluorescence—is the natural reader. This makes the pairing with a fluorometer the best match, since it directly measures the fluorescence signal produced by the labeled antibodies.

Chemiluminescence relies on light from a chemical reaction, so a luminometer is the typical reader; radioassays depend on radioactive emissions detected by a scintillation counter; turbidity is assessed by instruments that measure scattered light, like a nephelometer. While these other instruments are appropriate for their respective signal types, the fluorescence-based readout of immunofluorescence aligns best with a fluorometer.