selective detector

in chromatography
https://doi.org/10.1351/goldbook.09910

Detector which responds to a related group of components in the effluent.

Example: Spectroscopic detector that monitors all compounds with an absorbance at a particular wavelength.
Source:
PAC, 2017, 90, 181. (Terminology of separation methods (IUPAC Recommendations 2017)) on page 201 [Terms] [Paper]