1). Synthesis of bioactive materials for tissue engineering

Focus: Biodegradable polymers, dendrimers, hyperbranched polymers, bottle brush polymers

Develop new injectable bioactive tissue repair materials for precise treatment based on minimally invasive techniques to address high surgical trauma, slow repair, and narrow indications problems in bone, tendon, ligament, spine, and nerve injury regenerations.t

Selected Publications:

1.      Liu X, Camilleri ET, Li L, Gaihre B, Rezaei A, Park S, Miller AL, Tilton M, Waletzki BE, Terzic A, Elder BD, Yaszemski MJ, Lu L. Injectable catalyst-free “click” organic-inorganic nanohybrid (click-ON) cement for minimally invasive in vivo bone repair. Biomaterials, 2021, 276, 121014. (IF 15.3)

2.      Liu X, Gaihre B, Li L, Rezaei A, Tilton M, Elder BD, Lu L. Bioorthogonal “Click Chemistry” Bone Cement with Bioinspired Natural Mimicking Microstructures for Bone Repair. ACS Biomater. Sci. Eng., 2023, 9, 1585−1597. 

3.      Liu X, Miller AL, Xu H, Waletzki BE, Lu L. Injectable Catalyst-Free Poly (Propylene Fumarate) System Cross-Linked by Strain Promoted Alkyne–Azide Cycloaddition Click Chemistry for Spine Defect Filling. Biomacromolecules, 2019, 20 (9), 3352-3365. 

4.  Liu X, Miller AL, Fundora KA, Yaszemski MJ, and Lu L. Poly(ε-caprolactone) Dendrimer Cross-Linked via Metal-Free Click Chemistry: Injectable Hydrophobic Platform for Tissue Engineering. ACS Macro Lett., 2016, 5, 1261−1265. 

2). Fabrication of bioactive scaffolds for tissue engineering

Focus: 3D printing of polymers, 3D bioprinting of polymers with stem cells

Using digital intelligent manufacturing and 3D printing technology to develop 3D scaffolds and devices with desired shape and porosity, or using 3D bioprinting technology to integrate stem cells and polymer scaffolds into one combined complex, and incorporate with growth factors and immuno-regulators for expedited bone, nerve, and spine injury repair.

Selected Publications:

1. Liu X, Gaihre B, Park S, Li L, Dashtdar B, Astudillo Potes MD, Terzic A, Elder BD, Lu L. 3D-Printed Scaffolds with 2D Hetero-Nanostructures and Immunomodulatory Cytokines Provide Pro-healing Microenvironment for Enhanced Bone Regeneration.  Bioactive Materials, In press, 2023. (IF 16.8)

2.      Liu X, George MN, Park S, Miller AL, Gaihre B, Li L, Waletzki BE, Terzic A, Yaszemski MJ, Lu L. 3D-Printed Scaffolds with Carbon Nanotubes for Bone Tissue Engineering: Fast and Homogeneous One-Step Functionalization. Acta Biomaterialia, 2020, 111, 129-140. (IF 10.6)

3.      Liu X, Miller AL, Park S, M.N. George, Waletzki BE, Xu H, Terzic A, Lu L. Two-Dimensional Black Phosphorus and Graphene Oxide Nanosheets Synergistically Enhance Cell Proliferation and Osteogenesis on 3D Printed Scaffolds. ACS Appl. Mater. Interfaces, 2019, 3, 11, 23558-23572. (Cover Story) (IF 10.3)

4.      Liu X, Gaihre B, George MN, Miller AL, Xu H, Waletzki BE, Lu L. 3D Bioprinting of Oligo(Poly(Ethylene Glycol) Fumarate) for Bone and Nerve Tissue Engineering. J. Biomed. Mater. Res. A, 2021, 109(1), 6-17. 

3). Building biomaterial-cell complex for tissue engineering

Focus:  Cell-inductive spheroids, multi-cell-organoids

In the face of the therapeutic needs of organ injuries, develop bioactive materials to regulate the functions of stem cell organoids, therefore, fit injury-site niche after implantation with further induction of desired immunomodulation and cell differentiation to build a pro-healing microenvironment for accelerated organ regeneration.

Selected Publications:

1.      Liu X, Li L, Gaihre B, Park S, Li Y, Terzic A, Elder BD, Lu L. Scaffold-Free Spheroids with Two-Dimensional Heteronano-Layers (2DHNL) Enabling Stem Cell and Osteogenic Factor Codelivery for Bone Repair. ACS Nano, 2022, 16, 2, 2741–2755. (IF 18.0)