Riaz Ramish, Waqar Hira, Ahmad Nasir M, Abbas Shah Rukh
Department of Industrial Biotechnology, Atta Ur Rahman School of Applied Biosciences, University of Sciences and Technology, Islamabad 44000, Pakistan.
Biosensors and Therapeutics Laboratory, School of Interdisciplinary Engineering & Science, National University of Sciences and Technology, Islamabad 44000, Pakistan.
Polymers (Basel). 2022 Jul 19;14(14):2915. doi: 10.3390/polym14142915.
Recently, dual-mode imaging systems merging magnetic resonance imaging (MRI) and ultrasound (US) have been developed. Designing a dual-mode contrast agent is complex due to different mechanisms of enhancement. Herein, we describe novel phase change nanodroplets (PCNDs) with perfluoropentane encapsulated in a pre-polyglycerol sebacate (pre-PGS) shell loaded with polyethylene glycol (PEG)-coated iron oxide nanoparticles as having a dual-mode contrast agent effect. Iron oxide nanoparticles were prepared via the chemical co-precipitation method and PCNDs were prepared via the solvent displacement technique. PCNDs showed excellent enhancement in the in vitro US much more than Sonovue microbubbles. Furthermore, they caused a susceptibility effect resulting in a reduction of signal intensity on MRI. An increase in the concentration of nanoparticles caused an increase in the MR contrast effect but a reduction in US intensity. The concentration of nanoparticles in a shell of PCNDs was optimized to obtain a dual-mode contrast effect. Biocompatibility, hemocompatibility, and immunogenicity assays showed that PCNDs were safe and non-immunogenic. Another finding was the dual-mode potential of unloaded PCNDs as T1 MR and US contrast agents. Results suggest the excellent potential of these PCNDs for use as dual-mode contrast agents for both MRI and US.
最近，已开发出融合磁共振成像（MRI）和超声（US）的双模态成像系统。由于增强机制不同，设计双模态造影剂很复杂。在此，我们描述了一种新型相变纳米液滴（PCNDs），其全氟戊烷包裹在载有聚乙二醇（PEG）包覆的氧化铁纳米颗粒的聚癸二酸甘油酯前体（pre-PGS）壳中，具有双模态造影剂作用。通过化学共沉淀法制备氧化铁纳米颗粒，通过溶剂置换技术制备PCNDs。PCNDs在体外超声成像中显示出比声诺维微泡更优异的增强效果。此外，它们引起了磁化率效应，导致MRI信号强度降低。纳米颗粒浓度的增加导致MR造影效果增强，但超声强度降低。优化PCNDs壳中纳米颗粒的浓度以获得双模态造影效果。生物相容性、血液相容性和免疫原性分析表明，PCNDs是安全且无免疫原性的。另一个发现是未负载的PCNDs作为T1 MR和US造影剂的双模态潜力。结果表明，这些PCNDs作为MRI和US的双模态造影剂具有优异的潜力。
