Atmospheric-Pressure Plasma Jet-Induced Graft Polymerization of Composite Hydrogel on 3D-Printed Polymer Surfaces for Biomedical Application

Abstract

Poly(lactic acid) (PLA) is currently the most widely used material in 3D printing. PLA has good mechanical properties, chemical stability, and biodegradability, but its surface is hydrophobic and cannot be effectively used. The growth metabolism of attachments, how to increase the strength of PLA with high brittleness, and 3D printing of PLA materials for the biomedical field have always been a topic of research by scientists. This experiment used fused filament fabrication (FFF) to prepare structures. First, the 3D-printed polymer surfaces were treated with an atmospheric-pressure plasma jet (APPJ) to make the surface hydrophilic and increase the number of polar functional groups on the surface. Then, UV photo-grafting polymerization of 2-hydroxyethyl methacrylate (HEMA), poly(ethylene glycol) methacrylate (PEGMA), and hydroxyapatite (HAp) was applied onto the 3D-printed polymer surfaces. The experimental results of the water contact angle for the wettability test show that APPJ-treated and UV-grafted composite hydrogels become hydrophilic to activate the 3D-printed polymer surface successfully. For the in vitro study, the effect of APPJ treatment and composite hydrogel on the viability of osteoblast-like MG63 cells was examined using the Alamar Blue cell viability assay, indicating that biocompatibility has been improved in this study. This method is expected to have potential in the application of bone scaffolds in the future.

Three-Dimensional Printing Strategies for Enhanced Hydrogel Applications

“…The challenges and needs identified across these diverse applications demonstrate the interdisciplinary and innovative nature of research in 3D-printed hydrogels. From enhancing biocompatibility and mechanical strength [22,23] to achieving precision in nanoparticle arrangement [24] and optimizing scaffold fabrication [25], the field is characterized by a relentless pursuit of solutions that bridge the gap between theoretical potential and practical application. As researchers continue to address these challenges, the field of 3D-printed hydrogels stands on the border of significant breakthroughs that promise to transform a wide range of industries and improve human health and well-being.…”

“…A pivotal area of focus is on the mechanical properties and structural integrity of hydrogels, with a significant body of work [2,22,23,49,56,57,59,60,62,65,[71][72][73][74]80] emphasizing the evaluation of tensile strength, compressive strength, elasticity, toughness, and viscoelastic properties. This emphasis is crucial for applications where mechanical integrity is paramount, such as tissue engineering scaffolds [119,121,122,129] and soft robotics [63].…”