Sustained-release microneedle system based on PCL/PLA and cerium/zinc-doped bioactive glass for gastric ulcer repair

Abstract

As gastric ulcers remain a significant clinical challenge, this study presents the development of a flexible microneedle system based on cerium/zinc-doped bioactive glass (CeZnBG) and a PCL/PLA matrix for targeted ulcer therapy. The design leverages the synergistic antioxidant and antibacterial properties of CeZnBG, combined with the localized drug delivery capability of microneedles, to enhance ulcer healing. CeZnBG was synthesized via high-temperature sintering at various temperatures (950 °C, 1050 °C, 1150 °C, and 1250 °C), and subsequently incorporated into PCL/PLA microneedles (PCMN) at doping concentrations of 0.5 %, 1.5 %, and 2.5 % to form composite materials. The structural and physicochemical characteristics of the CeZnBG-PCMN, were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), mechanical properties, differential scanning calorimetry (DSC), and X-ray photoelectron spectroscopy (XPS). In vitro assays, including ROS scavenging and cytocompatibility, were used to assess the bioactivity of the composites. The results demonstrated that PCMN containing 1.5 % CeZnBG maintained excellent cytocompatibility (with relative cell viability exceeding 80 %) while exhibiting notable antibacterial performance, indicating promising potential for targeted gastric ulcer repair.