MRI -Specific Contrast Agents for Molecular Imaging: A Systematic Review

Introduction: Magnetic resonance imaging (MRI) contrast agents enhance the diagnostic capabilities of molecular imaging by providing critical insights into tissue composition and pathology. By selectively targeting molecular markers associated with diseases such as cancer and cardiovascular disorders, these agents enable higher specificity and sensitivity in disease detection. This study systematically reviews various MRI-specific contrast agents developed for molecular imaging, focusing on their applications, benefits, and limitations in clinical and research settings. Search Strategy: PubMed, Science Direct, Web of Science, and Google Scholar databases were explored up to October ۲۰۲۴, using different combinations of the keywords: 'Contrast Agent', 'Molecular Imaging', 'Magnetic Resonance Imaging', and 'MRI-specific'. Finally, eight more recent and relevant records were included in the study. Results: The developed MRI-specific contrast agents in the reviewed records included Gd-DO۳A-Tyr-(C۱۸)۲ (Gadolinium-loaded dodecane tetraacetic acid Tyr-(C۱۸)۲), PG-grafted Fe۳O۴ (Polyglycerol-grafted superparamagnetic iron oxide nanoparticles), MUC ۵AC-USPIO (Human gastric mucin-ultrasmall superparamagnetic iron oxide particles), CLT۱-(Gd-DTPA) (cyclic decapeptide CGLIIQKNEC-gadolinium-diethylene-triamine-pentaacetic acid), CLT۱-dL-(Gd-DOTA)۴ (small molecular peptide-targeted Gd-DOTA monoamide complex), Gd-DTPA-BOA (Gadolinium-diethylenetriamine-pentaacetic acid bis-oleate), PsL-EGFmAb-BSA۴-(Gd-DTPA) (P-selectin-targeted paramagnetic EGFmAb-BSA۴-(Gd-DTPA)), and Gd-containing PTPμ (protein tyrosine phosphatase mu). These contrast agents have been applied in MR imaging to detect diseases in various organs, including the liver, kidney, prostate, breast, and colon, as well as in assessing conditions like thrombosis and vascular diseases. Conclusion and Discussion: The integration of molecular imaging with high-resolution MRI holds significant promise for early disease detection and more accurate assessment of disease status using the newly developed contrast agents, primarily based on gadolinium and superparamagnetic iron oxide. These agents enhance MRI sensitivity and resolution, enabling more precise imaging of molecular and cellular processes. However, potential limitations such as toxicity, allergic reactions, kidney dysfunction, and high costs remain critical challenges. Recent research has focused on developing alternative formulations, such as biocompatible coatings and targeted delivery systems, to reduce adverse effects and improve safety profiles. Moreover, addressing the high production costs of these agents is crucial to ensure their broader clinical adoption. Further studies are essential to optimize the safety, effectiveness, and affordability of these novel agents, ensuring they meet clinical and research demands while maintaining high diagnostic standards.

کلیدواژه ها:

Contrast Agent ، Molecular Imaging ، Magnetic Resonance Imaging ، MRI-specific