Evaluation of allylated gelatin as a bioink supporting spontaneous spheroid formation of HepG2 cells.

The spheroid culture system has gained significant attention as an effective in vitro model to mimic the in vivo microenvironment. Even though numerous studies were focused on developing spheroids, the structural organization of encapsulated cells within hydrogels remains a challenge. Allylated gelatin or GelAGE is used as a bioink due to its excellent physicochemical properties.

Silymarin enriched gelatin methacrylamide bioink imparts hepatoprotectivity to 3D bioprinted liver construct against carbon tetrachloride induced toxicity.

Three-dimensional liver bioprinting is an emerging technology in the field of regenerative medicine that aids in the creation of functional tissue constructs that can be used as transplantable organ substitutes. During transplantation, the bioprinted donor liver must be protected from the oxidative stress environment created by various factors during the transplantation procedure, as well as from drug-induced damage from medications taken as part of the post-surgery medication regimen following the procedure. In this study, Silymarin, a flavonoid with the hepatoprotective properties were introduced into the GelMA bioink formulation to protect the bioprinted liver against hepatotoxicity.

Fabrication and evaluation of a bi-layered gelatin based scaffold with arrayed micro-pits for full-thickness skin construct.

There is an unmet need for a reliable and reproducible method for incorporating hair follicle derived stem cells in tissue engineered skin models to reconstitute hair follicles. This study discloses a novel method for introducing hair follicle derived stem cells in microneedle embossed micro-pits of a bilayer skin equivalent fabricated from a gelatin based scaffold. The microneedles are hard and strong enough to penetrate the upper layer of the bilayer gelatin based scaffold that corresponds to the epidermis and permeates down to lower layer that corresponds to dermal layer.

Biocompatibility evaluation of antioxidant cocktail loaded gelatin methacrylamide as bioink for extrusion-based 3D bioprinting.

Three-dimensional (3D) liver bioprinting is a promising technique for creating 3D liver models that can be used fordrug testing, hepatotoxicity studies, and transplantation. The functional performance of 3D bioprinted liver constructs are limited by the lack of cell-cell interactions, which calls for the creation of bioprinted tissue constructs with high cell densities. This study reports the fabrication of 3D bioprinted liver constructs using a novel photocrosslinkable gelatin methacrylamide (GelMA)-based bioink formulation.

High-throughput production of liver parenchymal microtissues and enrichment of organ-specific functions in gelatin methacrylamide microenvironment.

Liver parenchymal microtissues (LPMTs) are three-dimensional (3D) aggregates of hepatocytes that recapitulate in vivo-like cellular assembly. They are considered as a valuable model to study drug metabolism, disease biology, and serve as ideal building blocks for liver tissue engineering. However, their integration into the mainstream drug screening process has been hindered due to the lack of simple, rapid techniques to produce a large number of uniform microtissues and preserve their structural-functional integrity over the long term.

A Novel, Single Step, Highly Sensitive In-Vitro Cell-Based Metabolic Assay Using Honeycomb Microporous Polymer Membranes.

This study describes a novel, simple and versatile system for cell-based assays at the bench-top. The system consists of Polyurethane (PU) based honeycomb membrane with the active compounds/assay reagents dispensed on its pore linings. Membranes with functionalized pores were thus created and used for conducting cell based assays.

Evaluation of dynamic creep properties of surgical mesh prostheses--uniaxial fatigue.

In this study, we examine the dynamic creep behavior of four commonly used commercial hernia meshes (Prolene, Ultrapro, Vypro, and Vypro II). The meshes, differing from each other with respect to composition and architecture, were tested under uniaxial tension at simulated physiological loads and environmental conditions. The changes in percentage strain elongation, secant modulus, and cyclic energy dissipation over 100,000 cycles were compared.

The fabrication and characterization of biodegradable HA/PHBV nanoparticle-polymer composite scaffolds.

This study reports the fabrication and characterization of nano-sized hydroxyapatite (HA)/poly(hydroxyabutyrate-co-hydroxyvalerate) (PHBV) polymer composite scaffolds with high porosity and controlled pore architectures. These scaffolds were prepared using a modified thermally induced phase-separation technique. This investigation focuses on the effect of fabrication conditions on the overall pore architecture of the scaffolds and the dispersion of HA nanocrystals within the composite scaffolds.

Biological evaluation of pliable hydroxyapatite-ethylene vinyl acetate co-polymer composites intended for cranioplasty.

Hydroxyapatite (HAP) is undoubtedly a material suitable for repairing the defective bone tissue. However, the brittleness and non-malleability of HAP limit its clinical application as a cranioplastic analogue. To improve these properties, pliable, osteoconductive composites composed of HAP and ethylene vinyl acetate co-polymer (EVA) have been developed.

Effect of vinyl acetate content on the sintering behavior of hydroxyapatite-ethylene vinyl acetate copolymer composites.

Ethylene vinyl acetate copolymer (EVA) alone could be used as a binder material for the fabrication of hydroxyapatite (HAP) into intricate shapes for various bone substitute applications. It was observed that as the vinyl acetate content in the polymer was increased from 12 to 28 wt % an increase in the sintered density of the HAP was observed. Retention of the shapes of HAP in the molded form was also observed.