Polymer magnetic particle composite ultrasonic imaging microsphere

Abstract

The invention discloses a polymer magnetic particle composite ultrasonic imaging microsphere. The microsphere has a hollow inorganic / organic / inorganic three-layer structure, wherein a cavity is formed in the center of the microsphere and is filled with air inside; Fe3O4 magnetic particles are formed on the outer layer of the cavity; an intermediate layer is formed by a core / shell polymer nano microsphere obtained through free radical copolymerization of a poly(isopropyl acrylamide)-polymethylacrylic acid random copolymer, polymethylacrylic acid and divinyl benzene; coordinate bonds or ionic bonds can be formed between the copolymer and the Fe3O4 magnetic particles on the inner layer of the copolymer via carboxyl on the inner surface of the microsphere and iron salt, so that the microsphere is stable; an outer layer is formed by silicon dioxide and is connected with the intermediate layer through hydrogen-bond intersection between carboxyl on the surface of the microsphere and silicon hydroxyl on the surface of silicon dioxide. The material has the advantages that the polymer microsphere belongs to nanoparticles; a contrast agent can achieve targeted localization via the Fe3O4 magnetic particles on the inner layer; the silicon dioxide hollow microsphere has good biocompatibility and mechanical stability, and the inside cavity can generate strong echo signals in a contrast mode.

Description

technical field [0001] The invention relates to a contrast agent for medical detection, in particular to a multilayer organic / inorganic composite structure nano microsphere with magnetic function, which belongs to the field of medical technology. Background technique [0002] In recent years, molecular imaging technology has attracted extensive attention because it can provide important information for the diagnosis and monitoring of diseases in living tissues (Campbell R. E., Chang C. J. Curr Opin Chem Biol , 2010, 14(1):1-2.). Among many imaging modes, ultrasound imaging, as a non-invasive biomedical imaging mode, has important research value due to its advantages of safe and timely imaging and diagnosis, low price, lightness and quickness, and wide application. However, the difference in echo signals between different biological tissues often hinders the accuracy of diagnosis. In order to better obtain accurate information of specific tissues, people usually use the meth...

AI Technical Summary

Problems solved by technology

However, this method still has certain limitations, such as hollow SiO 2 The size of the spheres is too large and does not reach the nanoscale structure, which makes it difficult to be used for in vivo imaging, and it is difficult to carry out further connection without functional group modification

Therefore, the contrast agents currently used in clinical practice cannot simultaneously meet the requirements of good biocompatibility, mechanical stability, targeting performance, nanostructure, and functional group modification.

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