The manufacture of 3D scaffolds with specific controlled porous architecture, defined microstructure and an adjustable degradation profile was achieved using two-photon polymerization (TPP) with a size of 2  ×  4  ×  2 mm3. Scaffolds made from poly(D,L-lactide-co-ɛ-caprolactone) copolymer with varying lactic acid (LA) and ɛ -caprolactone (CL) ratios (LC16:4, 18:2 and 9:1) were generated via ring-opening-polymerization and photoactivation. The reactivity was quantified using photo-DSC, yielding a double bond conversion ranging from 70% to 90%. The pore sizes for all LC scaffolds were see 300 μm and throat sizes varied from 152 to 177 μm. In vitro degradation was conducted at different temperatures; 37, 50 and 65 °C. Change in compressive properties immersed at 37 °C over time was also measured. Variations in thermal, degradation and mechanical properties of the LC scaffolds were related to the LA/CL ratio. Scaffold LC16:4 showed significantly lower glass transition temperature (Tg) (4.8 °C) in comparison with the LC 18:2 and 9:1 (see 32 °C). Rates of mass loss for the LC16:4 scaffolds at all temperatures were significantly lower than that for LC18:2 and 9:1. The degradation activation energies for scaffold materials ranged from 82.7 to 94.9 kJ mol−1. A prediction for degradation time was applied through a correlation between long-term degradation studies at 37 °C and short-term studies at elevated temperatures (50 and 65 °C) using the half-life of mass loss (Time (M1/2)) parameter. However, the initial compressive moduli for LC18:2 and 9:1 scaffolds were 7 to 14 times higher than LC16:4 (see 0.27) which was suggested to be due to its higher CL content (20%). All scaffolds showed a gradual loss in their compressive strength and modulus over time as a result of progressive mass loss over time. The manufacturing process utilized and the scaffolds produced have potential for use in tissue engineering and regenerative medicine applications.

Intrinsically disordered protein polymers (IDPPs) have attracted a lot of attention in the development of bioengineered devices and use as molecular biology study models due to their biomechanical properties and stimuli-responsiveness. The present work aims to understand the effect of charge distribution on self-assembly of IDPPs. To that end, a library of recombinant IDPPs based on an amphiphilic diblock design with different charge distributions were bioproduced and their supramolecular assembly characterized on the nano-, meso-and microscale. Although phase transition was driven by the collapse of hydrophobic moieties, hydrophilic block composition strongly affected hierarchical assembly and, therefore, enabled the production of new molecular

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The efficiency of two-photon polymerization (TPP) techniques depends on the photoinitiator (PI) systems. Objective of this study was to enhance the performance of a cyclopentanone-based PI by introducing polar side chains in order to increase the solubility of the PI in the investigated macromonomers urethanedimethacrylate (UDMA) and lactide-caprolactone-methacrylate (LCM). The conditions for TPP were investigated in writing power/speed arrays. To confirm the high reactivity of the new PI a maximum speed experiment at a concentration of 2% was performed and a TPP structure in the dimensions of several centimeters could be written, which to our knowledge has not yet been reported elsewhere. materials have the potential to replace state-of-the-art implants and allografts. [5,7] It is common knowledge, that in vivo nearly all tissue cells reside in a 3D extracellular matrix (ECM). For that reason, the establishment of 3D scaffolds to reproduce the complex and dynamic environment of tissues and organs is directly associated with the development and adaptation of a variety of fabrication processes to meet the requirements of cell growth, organization, and differentiation. Having in mind, the enormous importance of hierarchical structures, for example, of biological load carriers like bones, tendons, or ligaments, techniques like TPP gain valuable ground, which allow the [*] Prof.

Elastin‐like recombinamers (ELRs) are biological polymers that due to their flexibility in the design, their self‐assembly properties, easy chemical modification allowing the introduction of many interesting functionalities, versatility to be processed in many forms (aggregates, fibers, layers, nanoparticles, or hydrogels), and excellent cyto‐ and biocompatibility have great potential in many fields, including drug delivery, tissue engineering, protein purification, anticancer gene therapies, and nanovaccines. In the next pages, we explore the evolution of ELRs from their ancient chemical origin to the most cutting‐edge bioproduction techniques, exploring several hosts that can be used to bioproduce them and their design versatility. We will also discuss several structures formed by ELRs and their potential medical applications.

A cellular coating based on hydrophobic interactions of an elastin-like recombinamer (ELR) with the cell membrane is presented. It is well-documented that biophysical properties such as net charge, hydrophobicity, and protein-driven cell–ligand (integrin binding) interactions influence the interaction of polymers, proteins or peptides with model membranes and biological cells. Most studies to enhance membrane–substrate interactions have focused on the introduction of positively charged groups to foster electrostatic interactions with the negatively charged membrane. Herein, we present an antagonistic approach based on ELRs with varying amounts of hydrophobic cholesteryl groups (ELR CTA s). The ability of the membranes to stabilize cholesteryl groups is hypothesized to assist the coordination of hydrophobic ELRs with the membrane. The main objective was to generate a defined cellular coating of a recombinant protein that allows for total sequence control and less host, or batch-to-batch, variation as a substitute for the existing coatings like alginate, polyelectrolytes, collagens, and fibronectin. We used an in vitro cell-binding assay to quantify cell–substrate interactions, showing enhanced cellular recognition and matrix distribution with an increasing number of cholesteryl groups incorporated. These novel materials and the versatile nature of their protein sequence have great potential as cellular markers, drug carriers, or hydrophobic cell-binding domains.

The diversity of nature including biopolymers, organisms, or active molecules and the fact that these natural systems can be transformed to be used for other purposes, enables a myriad of promising starting points for new developments. Here, Elastin-like recombinamers (ELRs) as a class of Abstract groups to foster electrostatic interactions with the negatively charged membrane. Herein we present an antagonistic approach based on ELRs with varying amounts of hydrophobic cholesteryl groups (ELR CTA s). The ability of membranes to stabilize cholesteryl groups is hypothesized to assist the coordination of hydrophobic ELRs with the membrane. The main objective was to generate a defined cellular coating of a recombinant protein that allows for total sequence control and less host, or batch-to-batch, variation as a substitute for existing coatings like alginate, polyelectrolytes, collagens and fibronectin. We used an in vitro cell-binding assay to quantify cellmembrane interactions, with the substrates showing enhanced cellular recognition and matrix distribution with an increasing number of cholesteryl groups incorporated. These novel materials and the versatile nature of their protein sequence have great potential as cellular markers, drug carriers, or hydrophobic cell-binding domains.

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