Radiology Department of the Tenth People's Hospital, The Institute for Biomedical Engineering and Nano Science, Tongji University School of Medicine, Shanghai, People's Republic of China.
Department of Radiology, Shanghai Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
Int J Nanomedicine. 2014 Mar 27;9:1601-15. doi: 10.2147/IJN.S58334. eCollection 2014.
Targeted imaging contrast agents for early pancreatic ductal adenocarcinoma diagnosis was developed using superparamagnetic iron oxide nanoparticles (SPIONs). For phase transfer of SPIONs, the hydrophobic SPIONs are first treated with tetrafluoroborate and then capped by bovine serum albumin (BSA) via ligand exchange. It was experimentally found that nitrosyl tetrafluoroborate pretreatment and proper structures of molecules are essential to the effective surface functionalization of SPIONs. Nonspecific binding was found to be significantly reduced by BSA surface functionalized hydrophobic SPIONs (BSA·SPIONs). The BSA·SPIONs were monodispersed with an average size of approximately 18.0 nm and stable in a wide pH range and various ionic strengths even after 7 days of storage. The longitudinal and transverse proton relaxation rate (r1, r2) values of the BSA·SPIONs were determined to be 11.6 and 154.2 s(-1) per mM of Fe(3+) respectively. The r2/r1 ratio of 13.3 ensured its application as the T2-weighted magnetic resonance imaging contrast agents. When conjugated with near-infrared fluorescent dye and monoclonal antibody, the (dye)BSA·SPION-monoclonal antibody bioconjugates showed excellent targeting capability with minimal nonspecific binding in the bimodal imaging of pancreatic cancer cells. The experimental approach is facile, environmentally benign, and straightforward, which presents great promise in early cancer diagnosis.
使用超顺磁性氧化铁纳米粒子（SPIONs）开发了用于早期胰腺导管腺癌诊断的靶向成像造影剂。为了实现 SPIONs 的相转移，首先用四氟硼酸处理疏水性 SPIONs，然后通过配体交换用牛血清白蛋白（BSA）进行封端。实验发现，亚硝酰四氟硼酸预处理和分子的适当结构对于 SPIONs 的有效表面功能化是必不可少的。通过 BSA 表面功能化疏水性 SPIONs（BSA·SPIONs），发现非特异性结合显著降低。BSA·SPIONs 具有单分散性，平均粒径约为 18.0nm，在宽 pH 范围和各种离子强度下稳定，即使在储存 7 天后也是如此。BSA·SPIONs 的纵向和横向质子弛豫率（r1，r2）值分别为 11.6 和 154.2 s(-1)每 mM 的 Fe(3+)。13.3 的 r2/r1 比值确保了其作为 T2 加权磁共振成像造影剂的应用。当与近红外荧光染料和单克隆抗体结合时，（染料）BSA·SPION-单克隆抗体生物缀合物在胰腺癌细胞的双模态成像中表现出出色的靶向能力，并且非特异性结合最小。该实验方法简便、环保且直接，在早期癌症诊断中具有很大的应用前景。
