Rheolution's Resources in Life Sciences

Dr. Daniel J. Kelly and his team at Trinity College Dublin researched how changing the formulation of an alginate bioink can alter the mechanical properties of a 3D printed scaffold. Like preparing a sauce, the consistency of a bioink can be adjusted by changing the concentration of its ingredients. However, it's more complex in biomedical research and requires analytical tools for quantification. Alginate, a natural biomaterial from algae, can quickly crosslink in the presence of ions (like Ca2+), forming a cohesive hydrogel with tunable properties. This makes it an ideal bioink for 3D bioprinting in tissue engineering and drug delivery.

During this last month, we explored the use of decellularized extracellular matrices (dECM) in tissue engineering and cell culture. dECM provides a natural scaffold for cells, containing the necessary biochemical cues and structural support to mimic native tissues. In one study, researchers from Trinity College Dublin investigated how the formulation of an alginate bioink can modulate the mechanical properties of 3D printed scaffolds. Alginate, a natural biomaterial derived from algae, is commonly used as a bioink due to its viscosifying, gelling, and biocompatible properties. The researchers examined different formulations of the bioink, varying the degree of polymerization and the type of divalent cations used for crosslinking. They evaluated the mechanical properties of the resulting scaffolds and assessed their suitability for tissue engineering applications. This work highlights the importance of optimizing bioink formulations to achieve desired mechanical properties in 3D printed constructs.

Mechanical testing of soft tissues and organs is crucial for biomaterial development. A study from the University of Massachusetts compared different testing techniques and evaluated the impact of sample freezing on lung tissue. The findings highlighted variations in mechanical properties depending on the technique used and showed a slight difference between fresh and frozen samples. Standardized testing methods are necessary for reliable measurements and advancements in tissue engineering.

In the context of dental treatments and other applications like surface coatings and 3D printing, the use of light to transform deformable resins into rigid materials is well-known. Similarly, in biomedical applications, photostimulation is used to modify the mechanical properties of hydrogels. Natural hydrogels have been chemically modified to allow precise control over their viscoelastic properties through light exposure. These photosensitive hydrogels can transition from a liquid to a gel state with varying levels of firmness based on formulation, light intensity, and exposure time. Matching the viscoelasticity of the hydrogel to the target organ is crucial in tissue engineering and regenerative medicine.

In a recent study, researchers from the University of California at Davis investigated the impact of the viscoelasticity of the cell's environment on bone formation by mesenchymal stromal cells (MSCs). They prepared alginate hydrogels with different mechanical properties and loaded them with MSC aggregates. The results showed that while both hydrogels supported high cell viability, the viscoelastic hydrogel promoted significantly higher calcium production by the cells compared to the elastic hydrogel. Calcium is an essential component for bone regeneration. These findings emphasize the importance of the cell's external environment, specifically its viscoelastic properties, in influencing cellular behavior and tissue regeneration.

A research study conducted by the University of Delaware explored whether the physiological differences in the maturation of specific brain regions could explain the increased risk-taking tendencies during adolescence. The study, titled "Viscoelasticity of reward and control systems in adolescent risk-taking" and published in the Neuroimage Journal, proposed that risk-taking behaviors are influenced by two opposing brain systems: the reward system (socioemotional system) and the cognitive control system, responsible for regulating impulsive responses. Due to the chronological development of these systems, an imbalance may occur, potentially making adolescents more prone to engaging in risky activities.