bound fraction

in radioanalytical chemistry
https://doi.org/10.1351/goldbook.B00718
The fraction of the incubation mixture which, after separation, contains the analyte bound to the binding @R05190@.
Source:
PAC, 1994, 66, 2513. (Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)) on page 2519 [Terms] [Paper]