磁纳米分子影像探针研究热点与挑战

 近年来,磁纳米材料在分子影像领域的应用得到科研人员的广泛关注。常用的磁性纳米探针是超顺磁性氧化铁颗粒（SPION）,它具有较好的水质子横向弛豫时间（T₂）弥散加权核磁共振成像造影剂的性能。通过对SPION制备及表面修饰进行改进,使纳米颗粒具有磁共振造影功能和干细胞标记、药物/基因递送的功能。综述了SPION兼具影像探针和磁共振成像可视化治疗方面的功能。虽然已有多种磁纳米材料进入临床研究,但结合当前研究瓶颈以及纳米药物制备方法的发展,制备造影效果较好、药物生物相容性较高、具有靶向性及临床转换潜力较强的SPION是新一代磁纳米探针研究亟需解决的问题。

Applications and challenge of magnetic resonance imaging probes

In recent years, apllications of magnetic nanomaterials in molecular imaging have attracted much attention. The superparamagnetic nanoparticle is the most popular magnetic nanoparticle due to its good T₂-weighted magnetic resonance imaging (MRI) contrast agent property. With the improvement of preparation and surface modification method, the superparamagnetic iron oxide particles (SPION) has been applied to imaging contrast, stem cell labeling and drug/gene delivery. This article reviews the combined applications of SPION in imaging contrast and MRI guided treatment. It also points out that many kinds of magnetic nanomaterials used for biomedical applications have low imaging contrast and specificity in vivo and have negative effecton living organism, which hinder the clinical application of SPION. Combined with the current public concerns and development of nanomedicine preparation methods, the preparation of SPION with good MRI contrast effect, high biocompatibility, disease area targeting and clinical conversion potential is a challenge to deal with in the new generation of magnetic nano-probes.