Novel High-Atomic-Number Element and Nanoparticle-Based CT Contrast Agents: Advanced Design Strategies and Clinical Translational Barriers.

In clinical medicine, computed tomography (CT) contrast media serve as vital diagnostic adjuncts that substantially elevate tissue contrast and diagnostic precision. This review systematically summarizes the latest advances in CT contrast agent research, focusing on four key areas: novel molecular design and synthesis strategies, optimization of pharmacokinetics and imaging performance, expansion of clinical application fields, and safety management including strategies to address adverse reactions. Despite considerable progress, challenges remain in improving biocompatibility, reducing toxicity, and tailoring agents for specific diagnostic needs. By providing a comprehensive overview of current research hotspots and unresolved issues, this article defines a specific translational framework aimed primarily at contrast agent development for human clinical patients, while systematically assessing the physical and biological boundaries that bridge preclinical small animal models to human diagnostic workflows. Crucially, we highlight key unresolved milestones, specifically focusing on the critical clinical translational barriers of nanoparticle-based agents, including long-term reticuloendothelial organ retention risks and global supply chain constraints inherent to rare High-Atomic-Number (high-Z) minerals.