Abstract

Magnetic resonance imaging (MRI) is a promising technique widely used in clinical diagnose. Poly(α-amino acid)s are excellent carriers for MRI due to their excellent biocompatibility. PDOPA-b-PSar copolymers (defined as “DoS”) are synthesized by sequential polymerizations of 3,4-dihydroxy-L-phenylalanine N-thiocarboxyanhydride (DOPA-NTA) and sarcosine N-thiocarboxyanhydride (Sar-NTA) initiated by neopentylamine in tetramethylene sulfone. Mn²⁺@DoS micelles have been prepared as T₁-weighted MRI contrast agents according to efficient coordination between catechol units and Mn²⁺ cation. High longitudinal relaxivity (27.7 mM⁻¹·s⁻¹) of Mn²⁺@PDOPA₁₂-b-PSar₇₂ was observed, and the aqueous micelle exhibits effective MRI contrast enhancement in vivo of nude mice. Mn²⁺@DoS shows potential clinical application in diagnostic radiology as a novel MRI contrast agent. Gd³⁺@DoS micelles are also investigated presenting a longitudinal relaxivity of 16.4 mM⁻¹·s⁻¹. Unfortunately, the Gd³⁺ loading percentage is quite low as 19%.

抽象的

磁共振成像（MRI）是一种广泛应用于临床诊断的有前途的技术。聚（α-氨基酸）由于具有出色的生物相容性，因此是MRI的极佳载体。PDOPA- b- PSar共聚物（定义为“ DoS”）是由新戊基胺引发的3,4-二羟基-L-苯丙氨酸N-硫代羧基酸酐（DOPA-NTA）和肌氨酸N-硫代羧基酸酐（Sar-NTA）顺序聚合而合成的四亚甲基砜。根据邻苯二酚单元与Mn ²⁺阳离子之间的有效配位，已将Mn ²⁺ @DoS胶束制备为T ₁加权MRI造影剂。Mn ²⁺ @PDOPA _12的高纵向弛豫性（27.7 mM ^-1 ·s ^-1）- b -PSar ₇₂中观察到，并且含水胶束显示出有效的MRI对比增强体内裸鼠。Mn ²⁺ @DoS作为一种新型MRI造影剂在放射诊断学中显示出潜在的临床应用。还研究了Gd ³⁺ @DoS胶束，其纵向弛豫度为16.4 mM ^-1 ·s ^-1。不幸的是，Gd ^3+的负载百分比非常低，仅为19％。