Journal Article

Enhancing bone repair ability of 3D-printed PLLA scaffolds via N-methyl-2-pyrrolidone etching

Xin, Huang, Shaohong, Wu, Jian, Cao, Jinlong, Li, Zhongxing, Liu, Yuanzheng, Wang, Qilin, Jiang

2026

Overview

The development of bone repair scaffolds has long been a research hotspot in tissue engineering. Owing to its unique capability for personalized customization of scaffold geometry and microstructure, 3D printing technology has been extensively adopted for fabricating bone repair scaffolds. Poly-L-lactic acid (PLLA), endowed with favorable biodegradability, excellent biocompatibility, and reliable in vivo safety, is widely used as a matrix material for 3D printed bone repair scaffolds. PLLA is a bioinert polymer characterized by inferior cell adhesion and osteogenic differentiation capabilities. To mitigate this bioinertness limitation, the present study employed N-methylpyrrolidone (NMP) etching to modify the surface of 3D-printed PLLA bone repair scaffolds. Following NMP etching for 1–24 h, the originally smooth scaffold surface evolved into a hierarchical, petal-like gradient microstructure, accompanied by a marked increase in surface roughness. Correspondingly, the hydrophilicity of the treated scaffolds was also enhanced. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses further confirmed that the crystallinity of PLLA in the scaffolds was significantly enhanced. Concomitantly, the modified scaffolds exhibited a marked improvement in adsorption capacity for green fluorescent protein (GFP), while the adhesion and proliferation of MC3T3-E1 on their surface were also significantly promoted. In vivo animal experiments demonstrated that the NMP-etched scaffolds could accelerate the process of bone defect repair. Collectively, surface modification of 3D-printed PLLA bone scaffolds via NMP etching enables precise modulation of their physicochemical properties, thereby effectively mitigating the inherent bioinertness limitation of PLLA scaffolds. Graphical Abstract

• Publisher: Springer US,Springer Nature B.V,Springer
• Subject: 3-D printers / Acids / Adhesion / Adsorption / Animals / Biocompatibility / Biocompatible Materials - chemistry / Biodegradability / Biodegradation / Biological activity / Biomaterials / Biomedical Engineering and Bioengineering / Bone healing / Bone Regeneration / Calorimetry / Calorimetry, Differential Scanning / Cell Adhesion / Cell adhesion & migration / Cell culture / Cell Differentiation / Cell Line / Cell Proliferation / Ceramics / Chemistry and Materials Science / Composites / Contact angle / Crystal defects / Defects / Differential scanning calorimetry / Differentiation (biology) / Etching / Fluorescence / Fourier transforms / Glass / Green fluorescent protein / Materials Science / Materials Testing / Mechanical properties / Mice / Microstructure / N-Methyl-2-pyrrolidone / Natural Materials / Osteogenesis / Physicochemical properties / Plasma etching / Polyesters - chemistry / Polylactic acid / Polymer Sciences / Polymers / Printing, Three-Dimensional / Proteins / Pyrrolidinones - chemistry / Regenerative Medicine/Tissue Engineering / Scaffolds / Software / Spectrum analysis / Surface Properties / Surface roughness / Surfaces and Interfaces / Thin Films / Three dimensional printing / Tissue engineering / Tissue Engineering - methods / Tissue Engineering Constructs and Cell Substrates / Tissue Scaffolds - chemistry / X-Ray Diffraction