In this study, the tumor-targeted MRI contrast agent was prepared with gelatinase-stimuli nanoparticles (NPs) and Omniscan (Omn) by double emulsion method. The size, distribution, morphology, stability, drug loading, and encapsulation efficiency of Omn-NPs were characterized. The macroscopic and microscopic morphological changes of NPs in response to gelatinases (collagenases IV) were observed. The MR imaging using Omn-NPs as a contrast agent was evaluated in the oral squamous cell carcinoma models with Omn as a control. We found clear evidence that the Omn-NPs were transformed by gelatinases and the signal of T1-weighted MRI sequence showed that the tumor-to-background ratio was significantly higher in Omn-NPs than in Omn. The peak point of time after injection was much later for Omn-NPs than Omn. This study demonstrates that Omn-NPs hold great promise as MRI contrast agent with improved specificity and prolonged circulation time based on a relatively simple and universal strategy.

中文翻译：

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通过明胶酶刺激策略在口腔鳞状细胞癌中使用载有Omniscan的纳米粒子作为肿瘤靶向MRI造影剂。

在这项研究中，肿瘤靶向的MRI造影剂是由明胶酶刺激纳米颗粒（NPs）和Omniscan（Omn）通过双重乳液法制备的。对Omn-NPs的大小，分布，形态，稳定性，载药量和包封效率进行了表征。观察到响应明胶酶（胶原酶IV）的NPs的宏观和微观形态变化。在Omn作为对照的口腔鳞状细胞癌模型中，评估了使用Omn-NPs作为造影剂的MR成像。我们找到了明确的证据，表明Omn-NPs已被明胶酶转化，并且T1加权MRI序列信号显示，Omn-NPs中的肿瘤背景比明显高于Omn。Omn-NP注射后的高峰时间要比Omn晚得多。