Composite hydrogel scaffolds with controlled pore opening via biodegradable hydrogel porogen degradation

Abstract

Poly(β-amino ester) (PBAE) biodegradable hydrogel systems have garnered much attention in recent years due to their appealing properties for biomedical applications. These hydrogel systems exhibit properties similar to natural soft tissue, degrade in aqueous environments, and have easily tunable properties that have been well studied and understood. In most cases, tissue engineering scaffolds must possess a three-dimensional interconnected porous network for tissue ingrowth and construct vascularization. Here, PBAE properties were explored and systems were selected to serve as both the pore-forming agent and the outer matrix of a scaffold that exhibits controlled pore opening upon degradation. To our knowledge, this is the first demonstration of a biodegradable hydrogel porogen system entrapped in a degradable hydrogel outer matrix. Scaffolds were prepared, and the degradation, compressive moduli, and porosity were analyzed. An added advantage of a degradable porogen is the potential for controlled drug release, and a model protein was released from the porogen particles to demonstrate this application. Finally, pluripotent cells seeded onto predegraded scaffolds were viable during the first 24 h of exposure, and furthermore, cell tracking confirmed the presence of cells within the pores of the scaffold. Overall, these present studies demonstrate the possibility of using these biodegradable hydrogel porogen-matrix systems as tissue engineering scaffolding materials.

Degradable hydrogels for spatiotemporal control of mesenchymal stem cells localized at decellularized bone allografts

“…Altering the specific PEG and amine used in the condensation reaction used to form the PBAE macromers controls hydrogel degradation rate, but the variations in chemical structure makes predicting the resulting degradation rate difficult (30, 31). Alternately, PEG can be modified with d,l -lactide, glycolide, or ε-caprolactone functionalities to form tri-block copolymers to achieve hydrolytic degradation of hydrogels formed from these macromers (32).…”

Drug release from calcium sulfate-based composites

“…43 The method for loading lysozyme in the A11 PBAE gels was similar to that used with H6 PBAE gels in this study. Although the two polymers have different compositions, they also have some similarities as members of the PBAE family of hydrogels.…”

“…Although the two polymers have different compositions, they also have some similarities as members of the PBAE family of hydrogels. 32,34,35,43,44 Among this family of materials, a variety of possible combinations of diacrylates and amines can produce similar range of properties. 32,34,35,43,44 The similarities between these two PBAEs demonstrate the adaptability of this gel family to accommodate different formulations or drug types if needed.…”

3D Microporous Scaffolds Manufactured via Combination of Fused Filament Fabrication and Direct Laser Writing Ablation

“…The fabricated scaffolds imitate the native ECM and have an impact on the cells by biological, chemical and physical cues from the ECM. Therefore, subtle changes in the scaffold architecture determine cellular fate [57]. The pores are one of the key elements in the scaffold topography.…”