147. enzyme-linked immunosorbent assay (ELISA) A form of immunoassay where the enzyme is linked to a protein that can bind to a captured analyte and through the subsequent addition of the enzyme’s substrate generate a molecule that is detected using UV, fluorescence or luminescence.
148. epimer Stereoisomer with more than one chiral center that differs in the configuration at only one center.
149. epitope The part of an antigen that is recognized by the immune system (i.e., antibodies, B or T cells).
150. esterase A family of hydrolase enzymes that react with esters to form an acid and alcohol. Their activity commonly requires inhibition for robust quantitative analysis of ester analytes in biofluids.
151. ex vivo That which occurs outside a living organism.