The effect of Affimers F5 and G2 on fibrin network structure. Scaffold and Affimer proteins F5 and G2 were added to plasma clots and visualized using laser scanning confocal microscopy and scanning electron microscopy. For confocal images, clots were made with the addition of fluorescently labeled Alexa Fluor-488 fibrinogen. Z stacks of 30 slices over 20.30 µm were taken, 3-dimensional images of compiled Z stacks are presented. Clots were made with increasing concentrations of Affimer proteins (increasing Affimer:fibrinogen molar ratio). (A) Buffer-only control, (B) 1:1, (C) 5:1, and (D) 10:1 Affimer:fibrinogen molar ratio. Laser scanning confocal microscopy scale bar = 20 μm; scanning electron microscopy scale bar = 1 μm.