Abstract

The urgent necessity for early disease diagnosis and detection continues to drive innovation in imaging techniques and contrast agents. Nanoparticle-based bioimaging offers significant potential to enhance therapeutics, treatment management, and cancer diagnostics. In both clinical practice and biomedical research, nanoparticles (NPs) can serve as labeled carriers or biomarkers for tracking immunotherapy responses, contrast-enhancing agents for improved imaging, or signal amplifiers to increase specificity and sensitivity in the visualization of cellular and molecular mechanisms in vivo. The development of advanced imaging probes with controlled biodistribution, heightened sensitivity, improved contrast, multifunctionality, and enhanced temporal and spatial resolution is made possible by the unique chemical, magnetic, and optical properties of nanomaterials. These probes are particularly beneficial, to multi-modal imaging techniques such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), magnetic resonance imaging (MRI), and ultrasound (US). Finally, these characteristics contribute to clinical benefits, including personalized medicine, real-time monitoring of disease progression, AI-based design of nanoparticles (NPs) and earlier detection, addressing current limitations in oncologic imaging. This review highlights promising nanoparticle-based imaging strategies, including radiolabeled nanoparticles for dual/multimodal cancer imaging, bio-conjugated quantum dots (QDs) for in vivo and in vitro diagnosis and imaging, green-synthesized nanoparticles for cancer diagnostics, nanoparticle-enabled molecular imaging strategies for monitoring immunotherapy responses, MXene-based imaging systems, and nanoparticle-assisted image-guided therapies. Collectively, these imaging technologies present novel tools to resolve biological challenges, enhance the effectiveness of cancer treatments, and drive clinical translation, which ultimately improve patient outcomes and care. © 2025 Elsevier B.V.