Extended Data Fig. 2: Rheological properties and printability of mycelium inks.
From: Three-dimensional printing of mycelium hydrogels into living complex materials
(A) Apparent viscosity of hydrogel inks measured under steady shear conditions, indicating the shear thinning behaviour of inks containing varying concentrations of malt extract. (B) Storage (G’) and loss (G’) moduli of inks before and after inoculation obtained from oscillatory rheological measurements at increasing applied frequency. The data show that the printed inks are predominantly elastic over the entire range of probed frequencies. (C) Rheological response of inks under printing simulation conditions. The alternating oscillatory (grey area) and steady-state (white area) measurements show quick recovery of the storage modulus of the ink upon cessation of shear. (D) 3D printed grids obtain from inks with increasing yield strength of approximately 100 Pa (left) 400 Pa (middle) and >1000 Pa (right). The images indicate filament sagging and flowing for inks with low yield stress, whereas high-yield-stress inks lead to fragile and brittle grids. Optimal print results are achieved with inks at intermediate yield stress level. (E) Effect of height and line gap spacing on the minimum yield stress required to print hydrogel grids that resist gravity-induced distortion. LD and DN correspond to the line spacing and the filament diameter, respectively.
