Construct And Properties Of Novel¹⁹F/¹²⁹Xe MR Contrast Agents

Magnetic resonance imaging(MRI)is a common method for tumor detection.How to improve its detection sensitivity and accuracy has always been a problem.The development of new MRI contrast agents is an effective way to solve this problem.Traditional 1H MRI is subject to background signal interference in the body.19F has 100%natural abundance,a wide chemical shift range,the highest gyromagnetic ratio in heteronuclear,and the physiological concentration of 19F is below the detection limit.So 19F MRI is of an imaging technique with great application potential.Multimodal imaging can combine the advantages of different imaging technologies to provide more anatomical information and biological information to provide a more accurate diagnosis method for cancer.On the other hand,hyperpolarized 129Xe can obtain 10,000 times enhanced magnetic resonance signal,which shows a huge advantage in sensitivity over traditional magnetic resonance.However,it lacks targeting and often requires a carrier to give it more functions.We designed and constructed three novel magnetic resonance contrast agents for the detection of lung adenocarcinoma tumor cells.1.A new derivative of the cryptophane has been obtained for ultra-sensitive MRI detection for Cat B.The probe,combined with the detection of 129Xe Hyper-CEST signal,provide a methodfor responsive detection of Cat B with the changes in the chemical shift and signal intensity of 129Xe in the cage of cryptophane,which was caused by the structural changes in the side chains of cryptophane after the cleavage of bond caused by Cat B.The probe has good biocompatibility,and can achievesensitivedetection for the Cat B with low concentration of probe.2.We combine tumor-derived particles(T-mps)with perfluorobromooctane(PFOB)emulsionto obtain the structure ofPFOBemulsion@T-mps.T-mps detected the gaseous 129Xe signal and could homologously target A549 cells.PFOB emulsion@T-mps can realize the detection of 129Xe/19F dual-channel NMR signals and has the potential to be used in 129Xe and 19F dual-channel MRI.It can provide more abundant and unique information and provide a basis for accurate diagnosis and effective treatment of lung cancer.3.Common 19F contrast agents often have the problem of incompatibility in water solubility and sensitivity.We designed and synthesized a fluorine-containing porphyrin compound T(3,5-DTFMB)P corresponding frozen micelle,which has the advantages of simple preparation,high fluorine loading,good water solubility,uniformity and stability,and has the potential to be used in tumor 19F MRI.