To replicate functional liver tissue in vitro for drug testing or transplantation, 3D tissue engineering requires representative cell models as well as scaffolds that not only promote tissue production but also are applicable in a clinical setting. Recently, adult liver‐derived liver organoids are found to be of much interest due to their genetic stability, expansion potential, and ability to differentiate toward a hepatocyte‐like fate. The current standard for culturing these organoids is a basement membrane hydrogel like Matrigel (MG), which is derived from murine tumor material and apart from its variability and high costs, possesses an undefined composition and is therefore not clinically applicable. Here, a cellulose nanofibril (CNF) hydrogel is investigated with regard to its potential to serve as an alternative clinical grade scaffold to differentiate liver organoids. The results show that its mechanical properties are suitable for differentiation with overall, either equal or improved, functionality of the hepatocyte‐like cells compared to MG. Therefore, and because of its defined and tunable chemical definition, the CNF hydrogel presents a viable alternative to MG for liver tissue engineering with the option for clinical use.

Nowadays, it is common to analyze crystallization processes and crystalline products using two-dimensional image analysis. Various techniques exist but they are not fundamentally capable of capturing the full morphology of particles due to their limitation in two dimensions. This is particularly true when complex shapes, e.g., through agglomeration or broken crystals, occur. Here, an approach is presented in which potash alum crystals are sampled from a laboratory-scale reactor at six time points over the course of a crystallization process. Three-dimensional (3D) images of all crystals in the samples were obtained by microcomputed tomography and used for morphological characterization. The method directly yields volume and surface area distributions without the need for any assumption regarding particle morphology. Applying geometric crystal models allowed for a more detailed analysis of the crystals. In the example considered, it was shown that most crystals assumed nonideal shapes over the course of the process. The supporting model provides indication that the shapes approach ideality through face-independent crystal growth. Overall, more than 11 000 crystals were analyzed. In general, this work aims at demonstrating the potential of crystal analysis by means of microcomputed tomography and 3D image analysis.

This study investigates digestibility enhancements of lignocellulose from shock pretreatment, alkaline pretreatment, and combination. Shock pretreatment subjects aqueous slurries of lignocellulose to shock waves, which disrupts its structure rendering it more susceptible to hydrolysis. Alkaline pretreatment submerges the biomass in aqueous alkali (NaOH, Ca(OH) 2 ), which removes lignin and acetyl groups. As indicators of digestibility, cellulase (CTec3) and hemicellulase (HTec3) were used to saccharify the pretreated corn stover and the resulting filtrate which contains about 10% of the sugars. Shock is most effective when it precedes alkaline pretreatment, presumably because it opens the biomass structure and enhances diffusion of pretreatment chemicals. Lignocellulose digestibility from calcium hydroxide treatment improves significantly with oxygen addition. In contrast, sodium hydroxide is a more potent alkali, and thereby eliminates the need for oxygen to enhance pretreatment.At low hydroxide loadings (<4 g OH À /100 g dry biomass), both NaOH and Ca(OH) 2 provide similar increases in digestibility; however, at high hydroxide loadings, NaOH is superior. For animal feed, Ca(OH) 2 treatment is recommended, because residual calcium ions are valuable nutrients. In contrast, for methane-arrested anaerobic digestion, NaOH treatment is preferred because NaHCO 3 is a stronger buffer. At 50 C, shock pretreatment improves sugar yields at all NaOH loadings. The effect of shock is most pronounced when the no-shock control employed the same soakingand-drying procedure as the shock treatment. The recommended conditions are shock treatment (5.52 bar [abs] initial H 2 /O 2 pressure) followed by 50 C alkaline treatment with NaOH loading of 4 g OH À /100 g dry biomass for 1 h.

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