Holmium vanadate nanoparticles as a biosafe and efficient contrast agent for spectral CT imaging of gastritis and colitis.

The development of a biosafe and high-performance spectral computed tomography (CT) contrast agent for the specific and non-invasive diagnosis of gastrointestinal diseases represents a significant clinical need. Unlike conventional CT, which is susceptible to artifacts from polychromatic X-ray beams, spectral CT distinguishes itself by utilizing material-specific, energy-dependent attenuation data. This capability enables superior differentiation between tissue types, leading to reduced background noise and improved contrast specificity. In this study, we developed hyaluronic acid-functionalized holmium vanadate nanoparticles (HA-HoVO4 NPs) for targeted spectral CT imaging of gastritis and colitis. HA-HoVO4 NPs exhibited excellent biocompatibility, stability and high X-ray attenuation properties. Following oral administration, HA-HoVO4 NPs not only clearly delineated the gastrointestinal tract anatomy but also selectively accumulated in inflammatory regions in murine models of gastritis and colitis, demonstrating excellent targeting capability. The combination of HA-mediated targeting with spectral CT imaging significantly enhanced diagnostic sensitivity and accuracy. The findings indicate that HA-HoVO4 NPs represent a highly promising targeted spectral CT contrast agent, offering new possibilities for the precise and non-invasive diagnosis of gastrointestinal inflammatory diseases. This technology thus promises to advance inflammation identification and treatment efficacy evaluation under imaging guidance, thereby providing more reliable support for clinical diagnosis and management.