Jia Yanlong, Geng Kuan, Cheng Yan, Li Yan, Chen Yuanfeng, Wu Renhua
Department of Radiology, Second Affiliated Hospital, Shantou University Medical College, Shantou, China.
Department of Radiology, The First People's Hospital of Honghe Prefecture, Mengzi, China.
Front Chem. 2020 Apr 22;8:326. doi: 10.3389/fchem.2020.00326. eCollection 2020.
Theranostic agents are particles containing both diagnostic and medicinal agents in a single platform. Theranostic approaches often employ nanomedicine because loading both imaging probes and medicinal drugs onto nanomedicine particles is relatively straightforward, which can simultaneously provide diagnostic and medicinal capabilities within a single agent. Such systems have recently been described as nanotheranostic. Currently, nanotheranostic particles incorporating medicinal drugs are being widely explored with multiple imaging methods, including computed tomography, positron emission tomography, single-photon emission computed tomography, magnetic resonance imaging, and fluorescence imaging. However, most of these particles are metal-based multifunctional nanotheranostic agents, which pose potential toxicity or radiation risks. Hence, alternative non-metallic and biocompatible nanotheranostic agents are urgently needed. Recently, nanotheranostic agents that combine medicinal drugs and chemical exchange saturated transfer (CEST) contrast agents have shown good promise because CEST imaging technology can utilize the frequency-selective radiofrequency pulse from exchangeable protons to indirectly image without requiring metals or radioactive agents. In this review, we mainly describe the fundamental principles of CEST imaging, features of nanomedicine particles, potential applications of nanotheranostic agents, and the opportunities and challenges associated with clinical transformations.
诊疗试剂是在单一平台上同时包含诊断剂和药剂的颗粒。诊疗方法通常采用纳米医学，因为将成像探针和药物同时负载到纳米医学颗粒上相对简单，这可以在单一试剂中同时提供诊断和治疗能力。这种系统最近被称为纳米诊疗。目前，结合药物的纳米诊疗颗粒正在通过多种成像方法进行广泛探索，包括计算机断层扫描、正电子发射断层扫描、单光子发射计算机断层扫描、磁共振成像和荧光成像。然而，这些颗粒大多是基于金属的多功能纳米诊疗剂，存在潜在的毒性或辐射风险。因此，迫切需要替代性的非金属且生物相容的纳米诊疗剂。最近，结合药物和化学交换饱和转移（CEST）造影剂的纳米诊疗剂显示出良好的前景，因为CEST成像技术可以利用来自可交换质子的频率选择性射频脉冲进行间接成像，而无需金属或放射性试剂。在这篇综述中，我们主要描述了CEST成像的基本原理、纳米医学颗粒的特性、纳米诊疗剂的潜在应用以及与临床转化相关的机遇和挑战。
