colourimetric , also: colorimetric

Lieberman-Burchard is a reagent used in a colourimetric test to detect cholesterol, which gives a deep green colour.

Using a detection antibody conjugated to an enzyme or fluorophore the quantity of bound protein can be accurately measured by fluorometric or colourimetric detection.

(2001) Single-step multiplex RT-PCR for simultaneous and colourimetric detection of six RNA viruses in olive trees.

During the detection process the membrane is "probed" for the protein of interest with a modified antibody which is linked to a reporter enzyme, which when exposed to an appropriate substrate drives a colourimetric reaction and produces a colour.