Hydrophobically Modified Isosorbide Dimethacrylates as a Bisphenol-A (BPA)-Free Dental Filling Material.

A series of bio-based hydrophobically modified isosorbide dimethacrylates, with , , and benzoate aromatic spacers (ISBGBMA), are synthesized, characterized, and evaluated as potential dental restorative resins. The new monomers, isosorbide 2,5-bis(4-glyceryloxybenzoate) dimethacrylate (ISB4GBMA), isosorbide 2,5-bis(3-glyceryloxybenzoate) dimethacrylate (ISB3GBMA), and isosorbide 2,5-bis(2-glyceryloxybenzoate) dimethacrylate (ISB2GBMA), are mixed with triethylene glycol dimethacrylate (TEGDMA) and photopolymerized. The resulting polymers are evaluated for the degree of monomeric conversion, polymerization shrinkage, water sorption, glass transition temperature, and flexural strength.

Probing the textures of composite skin care formulations using large amplitude oscillatory shear.

Identifying meaningful and measurable rheological parameters that shadow the dynamic shear stresses sustained in the initial application and subsequent spreading of structured cosmetic formulations onto the skin is quite challenging. When applied to non-Newtonian soft solids, traditional oscillatory rheological testing tends to best correlate with the “at-rest” state, or, more fundamentally, with the initial and thermodynamically reversible perturbations in the physiochemical networking that binds components of the amalgamated microstructure. In addition, after yielding, as an applied film is further thinned while spreading on the skin surface, shear rates during flow processes may rapidly and dynamically increase to 10⁴ s⁻¹ , which is a magnitude that is not practically simulated with a standard rotational rheometer.

Shell-core bi-layered scaffolds for engineering of vascularized osteon-like structures.

Bottom-up assembly of osteon-like structures into large tissue constructs represents a promising and practical strategy toward the formation of hierarchical cortical bone. Here, a unique two-step approach, i.e.

Multifunctional protein-encapsulated polycaprolactone scaffolds: fabrication and in vitro assessment for tissue engineering.

Here we demonstrate the use of a twin screw extrusion/spiral winding (TSESW) process to generate protein-encapsulated tissue engineering scaffolds. Bovine serum albumin (BSA) was distributed into PCL matrix using both wet and hot melt extrusion methods. The encapsulation efficiency and the time-dependent release rate, as well as the tertiary structure of BSA (via circular dichroism), were investigated as a function of processing method and conditions.

Functionally graded beta-TCP/PCL nanocomposite scaffolds: in vitro evaluation with human fetal osteoblast cells for bone tissue engineering.

The engineering of biomimetic tissue relies on the ability to develop biodegradable scaffolds with functionally graded physical and chemical properties. In this study, a twin-screw-extrusion/spiral winding (TSESW) process was developed to enable the radial grading of porous scaffolds (discrete and continuous gradations) that were composed of polycaprolactone (PCL), beta-tricalciumphosphate (beta-TCP) nanoparticles, and salt porogens. Scaffolds with interconnected porosity, exhibiting myriad radial porosity, pore-size distributions, and beta-TCP nanoparticle concentration could be obtained.

Surface patterning of poly(L-lactide) upon melt processing: in vitro culturing of fibroblasts and osteoblasts on surfaces ranging from highly crystalline with spherulitic protrusions to amorphous with nanoscale indentations.

Large-scale and reproducible manufacturing of scaffolds for tissue engineering applications will necessitate the adoption of methods relying on the processing of the biodegradable polymers directly from the melt. Such solventless processing will give rise to bulk and surface properties that will differ significantly from those generated upon processing from solution-based methods. Thus, detailed understanding of the microstructures that are developed during melt processing and the resulting surface/cell interactions is needed.