TiO2 NPs improve ultrasound response: CS/β‑GP/TiO2 NP hydrogel enabling on‑demand administration

The present study developed a novel injectable, biocompatible, and thermosensitive hydrogel system for ultrasound‑triggered drug release, using a chitosan/sodium β‑glycerophosphate/titanium dioxide nanoparticle (CS/β‑GP/TiO₂ NP) composite. The inclusion of TiO2 NPs aimed to enhance ultrasound sensitivity, enabling precise therapeutic release to targeted tissues. The hydrogels displayed excellent injectability (maximum injection force <6.5 N) and gelled effectively at body temperature. Biocompatibility was confirmed through Cell Counting Kit‑8, LIVE/DEAD, and western blot assays. The present study demonstrated that hydrogels with TiO₂ NPs significantly increased the release rates of sodium fluorescein and bovine serum albumin, affirming the role of TiO₂ NPs as a sensitizer. This establishes the CS/β‑GP/TiO₂ NP hydrogel as a promising system for ultrasound‑responsive drug delivery. Potential applications include drug delivery, tissue engineering, and wound healing, with the system offering controlled and targeted therapy under ultrasound stimulation. Future research will optimize hydrogel properties, assess in vivo performance, and evaluate long‑term stability and effectiveness in clinical settings.