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Collagen type I, the main component of the extracellular matrix in vertebrates, is widely used in tissue engineering applications. This is on account that collagen molecules can self‐assemble under certain conditions into 3D fibrillar hydrogels. Although there is an extensive body of literature studying collagen self‐assembly, there is a lack of systematic understanding on how different experimental factors, such as pH and temperature, and their cumulative effects guide the self‐assembly process. In this work, a comprehensive workflow to study the interactive effects of several assembly parameters on the collagen self‐assembly process is implemented. This workflow consists of: 1) efficient statistical sampling based on Design of Experiments, 2) high‐throughput and automated data collection and 3) automated data analysis. This approach enables to screen several parameters simultaneously and derive a set of mathematical equations that link parameters with the kinetics and morphological aspects of collagen self‐assembly, and can be used to design collagen constructs with predefined characteristics. [ABSTRACT FROM AUTHOR]

Complex polymeric nanospheres were formed in water from comb-like amphiphilic block copolymers. Their internal morphology was determined by three-dimensional cryo-electron tomographic analysis. Varying the polymer molecular weight (MW) and the hydrophilic block weight content allowed for fine control over the internal structure. Construction of a partial phase diagram allowed us to determine the criteria for the formation of bicontinuous polymer nanosphere (BPN), namely for copolymers with MW of up to 17 kDa and hydrophilic weight fractions of ≤0.25; and varying the organic solvent to water ratio used in their preparation allowed for control over nanosphere diameters from 70 to 460 nm. Significantly, altering the block copolymer hydrophilic-hydrophobic balance enabled control of the internal pore diameter of the BPNs from 10 to 19 nm. [ABSTRACT FROM AUTHOR]

Diatoms are unicellular photosynthetic algae that produce a silica exoskeleton (frustule) which exposes a highly ordered nano to micro scale morphology. In recent years there has been a growing interest in modifying diatom frustules for technological applications. This is achieved by adding non-essential metals to the growth medium of diatoms which in turn modifies morphology, composition, and resulting properties of the frustule. Here, we investigate the frustule formation in diatom Pinnularia sp., including changes to overall morphology, silica thickness, and composition, in the presence of Al3+ ions at different concentrations. Our results show that in the presence of Al3+ the total silica uptake from the growth medium increases, although a decrease in the growth rate is observed. This leads to a higher inorganic content per diatom resulting in a decreased pore diameter and a thicker frustule as evidenced by electron microscopy. Furthermore, 27Al solid-state NMR, FIB-SEM, and EDS results confirm that Al3+ becomes incorporated into the frustule during the silicification process, thus, improving hydrolysis resistance. This approach may be extended to a broad range of elements and diatom species towards the scalable production of silica materials with tunable hierarchical morphology and chemical composition. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewandte Chemie International Edition" is presented.