label-free detection

https://doi.org/10.1351/goldbook.14154
Direct detection of compound activity on a target without the requirement for a labeled reagent.
Examples: Use of calorimetry, mass spectrometry, surface plasmon resonance, or nuclear magnetic resonance to measure a signal.
Source:
PAC, 2011, 83, 1129. (Glossary of terms used in biomolecular screening (IUPAC Recommendations 2011)) on page 1146 [Terms] [Paper]