A noninvasive precise treatment strategy for implant-related infections based on X-ray-induced luminescent/photodynamic therapeutic multilayered device surface materials

Conventional prophylaxis and treatment of implant-related infections via devices’ surface biofilm elimination include extensive non-targeting antibiotics prescription, invasive surgical intervention, and periodic implant replacement, with their inevitable relapses being lifelong guaranteed leading to financial burdens and drug resistance risks for patients. Herein, we propose a novel, sustainable modality of noninvasive precise treatment strategy based on potential theranostic, multilayered Gd³⁺ (UV), Eu³⁺ (red) and Tb³⁺ (green) doped Y(PO₃)₃ X-ray-induced luminescent matrix surface materials cum a nanolayer coating of titanium dioxide with pH indicators on implantable medical devices, which simultaneously integrate X-ray-initiated pH-sensitive NIR luminescence for location detection of biofilm infection, and X-ray-excited, UV-triggered deep-tissue-localized antimicrobial photodynamic therapy. The Y(PO₃)₃ crystal composite structures allow doping of rare earth ions at rarely high concentrations and produce high emission intensity even under less-detrimental low-dose X-ray radiation. The feasibility of such precise treatment strategy has been substantiated through various pH and inactivation experiments. With the growing aging population, this work aims to provide a potentially new, patient-friendly, (i.e. surgery/antibiotics-free and lower-cost) proof-of-principle theranostic resolution for the increasing incidence of orthopaedic implant-related biofilm infections, from preventive device maintenance to precise curative eradication.