Hr208

Scanning electron microscopy (SEM) images depicting the topography of corn bran and jejunal and ileal digesta samples from HF, XY, and AX at each period were captured using field emission SEM at the Roy J. Carter High Resolution Microscopy Facility (Iowa State University, Ames, IA). Samples were uniformly mounted on circular aluminum stubs with double-sided carbon tape and coated with platinum to a maximum thickness of 8 nm using a high-resolution sputter coater adapted with a high-resolution thickness controller (HR 208, Cressington Scientific Instruments Ltd, Watford, UK). Samples were examined with an ultra-low voltage cold cathode field emission scanning electron microscope (Hitachi S-4800, Hitachi, Krefeld, Germany) at a voltage of 10.0 kV. The corresponding dietary treatment and period for a given sample were blinded to the technician imaging the samples. Multiple representative pictures were captured at 100x magnification, and images were scaled with an associated software (4800 FE-SEM Hitachi Internal Software, Hitachi; Krefeld, Germany). A representative picture of each dietary treatment for each period was selected by a research technician blinded to dietary treatments and experimental hypotheses to avoid confirmation bias in selecting a representative image.

Scanning electron micrographs of synthesised polymers were acquired sputtering a thin layer of Au (20 nm) on the films using a sputter coater (CRESSINGTON HR208). A field emission scanning electron microscopy (FESEM) ULTRAPLUS, (Zeiss Company, Germany) equipped with OXFORD detector for EDX (EHT = 10.00 kV, aperture size = 30.00 µm, detector = EDT) was used to detect secondary electrons onto dry samples operating under vacuum conditions at 61.90 KX (Azo-tz-PEDOT:PSS), 59.79 KX (N₃-PEDOT:PSS) and 57.64 KX (PEDOT:PSS) of magnifications.