Organometallic chelate, as well as preparation method and application thereof, and probe

Abstract

The invention relates to an organometallic chelate, as well as a preparation method and application thereof, and a probe. The organometallic chelate has a structure as shown in the following formula (I): the micromolecular organometallic chelate can emit near-infrared two-region fluorescence, and can realize near-infrared two-region fluorescence and PET bimodal imaging. High relaxation rate and light stability can be maintained while infinite penetration depth and high-sensitivity imaging are realized; besides, elements of neodymium and gallium are chelated in the organometallic chelate, so that free neodymium atoms and free gallium atoms are prevented from being generated, the biological stability of a compound is improved, and the toxic and side effects of the compound on biological cells are reduced. Due to a RGD polypeptide structure, the compound can target glioma, and when the compound is used for brain operation, the spatial imaging resolution ratio of the brain glioma and the tumor boundary operation precision can be effectively improved.

Description

technical field [0001] The invention relates to the field of molecular / fluorescent dual-mode imaging probes, in particular to an organometallic chelate, a preparation method and application thereof, and a probe. Background technique [0002] In recent years, molecular imaging technology has provided a powerful tool for non-invasive diagnosis in vitro. Common molecular imaging techniques include magnetic resonance imaging, fluorescence imaging, positron emission tomography (PET), computed tomography (CT), photoacoustic imaging, and ultrasound imaging. Different molecular imaging technologies have unique advantages and disadvantages; for example, PET imaging can achieve unlimited penetration depth and high-sensitivity imaging, and can provide the metabolism of biological organs, which is currently the standard for clinical tumor diagnosis. Due to the decay characteristics of PET imaging probes, it is not suitable for real-time long-term observation of tumor development and ch...

AI Technical Summary

Problems solved by technology

Different molecular imaging technologies have unique advantages and disadvantages; for example, PET imaging can achieve unlimited penetration depth and high-sensitivity imaging, and can provide the metabolism of biological organs, which is currently the standard for clinical tumor diagnosis. Due to the decay characteristics of PET imaging probes, it is not suitable for real-time long-term observation of tumor development and changes; fluorescence imaging has high time resolution, simple equipment, and easy operation. With the help of molecular probes, tumors that are invisible to the naked eye can be " Precise lighting" can be applied in real time to surgical navigation and early diagnosis of tumors. However, the fluorescence emitted by the fluorescent probes used in current fluorescence imaging is mostly visible light and near-infrared fluorescence (NIR-I, 750nm-950nm). Compared with fluorescent probes that emit fluorescence in the second near-infrared region (NIR-II, 1000nm-1400nm and 1500nm-1700nm), fluorescent probes that emit fluorescence mostly in visible light and fluorescence in the first near-infrared region have stronger biological tissue absorption and Scattering effect, lower penetration depth and higher background fluorescence effect, low signal-to-noise ratio and sensitivity for in vivo imaging, greatly reduced glioma space for navigation in brain tumor surgery Imaging Resolution and Borderline Surgical Accuracy

[0003] At present, most of the probes for NIR imaging are nano-type probes, followed by small-molecule probes; nano-type probes have good EPR effects (that is, high tumor permeability and long retention effect) and drug It has the advantages of sustained release, etc., but has the disadvantages of easy accumulation of liver and spleen (enrichment effect of endothelial network tissue), low tumor uptake rate, and long residence time in the body. The clinical transformation of most nano-type probes has bottlenecks that are difficult to break through; while relatively Compared with nano-type probes, small-molecule probes have the advantages of small molecular weight, not easy to accumulate in the liver and spleen, easy to metabolize in the kidney, and can be flexibly modified for functionalization.

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