Fabrication and evaluation of 3D printed PLGA/nHA/GO scaffold for bone tissue engineering

Abstract

The study aimed to fabricate and evaluate a bone tissue engineering scaffold made from a composite of polylactic-co-glycolic acid (PLGA), nano-hydroxyapatite (nHA), and graphene oxide (GO) using low-temperature 3D printing and freeze-drying techniques. The scaffolds were produced with varying compositions: PLGA alone and in combination with nHA and GO. The macro and microstructure, pore size, porosity, mechanical properties, and in vitro biocompatibility were assessed. Bone marrow mesenchymal stem cells (BMSCs) were co-cultured with the scaffolds to evaluate cell adhesion, proliferation, and cytotoxicity. The PLGA/nHA/GO composite scaffolds exhibited optimal pore size and microtopography, enhanced mechanical properties, excellent water absorption, and appropriate degradability. The co-culture with BMSCs demonstrated improved cell adhesion and proliferation, indicating good biocompatibility. The PLGA/nHA/GO composite scaffolds show potential as a bone tissue engineering material due to their favorable properties and biocompatibility, suggesting their suitability for bone defect repair applications.

Keywords: 3D printing; Bone tissue engineering; Graphene oxide; Nano-hydroxyapatite; Polylactic-co-glycolic acid; Scaffold.

Fig. 1

Macroscopic morphological characterization of scaffolds. (a) Top view; (b) front view.

Fig. 2

Macroscopic pores of the scaffolds. (a) Macroscopic pores of the scaffolds under the microscope; (b) Pore size of the scaffolds; (*) p < 0.05, PLGA/nHA/GO compared with PLGA; (#) p < 0.05, PLGA/nHA/GO compared with PLGA/nHA; (c) Porosity of the scaffolds.

Fig. 3

SEM images of the scaffolds. (a) Magnification X 100, scar bar = 100 μm; (b) Magnification X 500, scar bar = 100 μm; (c) Magnification X 1000, scar bar = 100 μm.

Fig. 4

Mechanical properties of the scaffolds. (a) Stress-strain curves of the PLGA scaffold; (b) Stress-strain curves of the PLGA/nHA scaffold; (c) Stress-strain curves of the PLGA/nHA/GO scaffold.

Fig. 5

Water absorption of the scaffolds. Note: *P < 0.05 compared with the PLGA group and #P < 0.05 compared with the PLGA/nHA group at 6, 9, and 12 h.

Fig. 6

Degradability of scaffolds. (a) Mass loss of scaffolds; (b) degradation rates of scaffolds; (c) pH changes during scaffolds degradation. (*) p < 0.05, PLGA/nHA/GO compared with PLGA ; (#) p < 0.05, PLGA/nHA/GO compared with PLGA/nHA.

Fig. 7

Biocompatibility of scaffolds. (a) Cell adhesion rates of scaffolds; (b) Proliferation of scaffold-seeded cells overtime. (*)p < 0.05, PLGA/nHA/GO compared with PLGA; (#) p < 0.05, PLGA/nHA/GO compared with PLGA/nHA.