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Abstract One of the most fundamental characteristics of a biomaterial tailored for bone repair and regeneration is its ability to promote bone regeneration and healing of large defects. This work reports producing a functionalized and hieratically porous bone scaffold that significantly supports cell adhesion and proliferation by providing bone mimicry structure and controlled release of protein. The Slit Guidance Ligand 3 (SLIT3) protein was previously tested to promote bone formation and control the resorption process in natural bone healing. In this study, our goal was to design a nanocomposite bone scaffold to be functionalized with SLIT3 protein and then evaluate the uptake and release profile from surface into culture media to support bone marrow-derived mesenchymal stem cells (MSC) 3D culture. Indirect 3D printing of a polylactic-co-glycolic acid (PLGA), hydroxyapatite nanoparticles, and polydopamine coated (PLGA-HANPs-PDA) was utilized to obtain a hierarchically porous and SLIT3 protein-releasing scaffold. The produced scaffold was evaluated and optimized using chemical, architectural, mechanical, and biological characterization techniques. Optimal physicochemical properties resulted in a unique microstructure with an average pore size of 178.06 ± 45 µm, 63% porosity, and stable and homogenous chemical composition. Mechanical testing demonstrated a compression strength up to 1.5 MPa at 75% strain, with a compression modulus of 0.58 ± 0.05 MPa. Preliminary biological experiments showed that the scaffold exhibited gradual SLIT3 protein release, biodegradability, and reliable biocompatibility for MSC cell culture. Finally, we showed for first time the bioactivity of SLIT3 protein within PLGA-HANPs-PDA scaffold to promote attachment and growth of mesenchymal stem cell (MSCs) seeded in bone mimicry scaffold matrix. The collected findings will serve as a bedrock for thorough and targeted in vitro studies to evaluate anticipated osteogenesis the MSCs.
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This content will become publicly available on December 1, 2025
A Multi‐functional Hybrid System Comprised of Polydopamine Nanobottles and Biological Effectors for Cartilage Repair
Abstract Biological effectors play critical roles in augmenting the repair of cartilage injuries, but it remains a challenge to control their release in a programmable, stepwise fashion. Herein, a hybrid system consisting of polydopamine (PDA) nanobottles embedded in a hydrogel matrix to manage the release of biological effectors for use in cartilage repair is reported. Specifically, a homing effector is load in the hydrogel matrix, together with the encapsulation of a cartilage effector in PDA nanobottles filled with phase‐change material. In action, the homing effector is quickly released from the hydrogel in the initial step to recruit stem cells from the surroundings. Owing to the antioxidation effect of PDA, the recruited cells are shielded from reactive oxygen species. The cartilage effector is then slowly released from the nanobottles to promote chondrogenic differentiation, facilitating cartilage repair. Altogether, this strategy encompassing recruitment, protection, and differentiation of stem cells offers a viable route to tissue repair or regeneration through stem cell therapy.
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- Award ID(s):
- 2137669
- PAR ID:
- 10641718
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Small
- Volume:
- 20
- Issue:
- 50
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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