Figure 1.

Real-time ex vivo monitoring of first-pass phenolic metabolism using the everted gut sac technique. The apparent permeability (Papp) and biotransformation of bioaccesible phenolic compounds (PC) and their associated first-pass metabolites were followed by spectrophotometry (Folin–Ciocalteau; 120 min), HPLC-ESI-QTOF-MS (120 min) and, differential pulse voltammetry (DPV; 0 to 120 min). Diffusion from apical (A; out) to basolateral (B; in) and B-A were considered permeability and efflux, respectively.