RESUMEN
Though nanoparticles are being used for several biomedical applications, the safety of the same is still a concern. It is very routine procedure to check the preliminary safety aspects of the particles intended for in vivo applications. The major tests include how the material reacts to a normal cell, how it behaves with the blood cells and also whether any lysis take place in the presence of these materials. Here we present these test data of two novel nanomaterials designed for its use as contrast agent for magnetic resonance imaging and a multimodal contrast agent for targeted liver imaging. On proving the biosafety, the materials were tested for Magnetic Resonance Angiography using normal rats as model. The data of the same were clear identification of the prominent vascular structures and is included as the colour coded MRI image. Lateral and oblique view data are also presented for visualizing other major blood vessels.
RESUMEN
In magnetic resonance imaging (MRI), gadolinium (Gd) complexes are very often used as contrast agents to enhance the signal from soft tissue deformities and vascular anomalies, to improve the accuracy of diagnosis. The safety concern of using Gd complexes in renally compromised patients pose limitations on its application. To overcome this scenario, we introduce a nontoxic zerovalent iron based nanoparticle as a novel contrast agent for MR angiography and a hybrid version of the same to serve as a dual function contrast agent for targeted liver imaging. The synthesized zerovalent iron (ZVI) nanoparticles after citrate stabilization (C@ZVI) had an average size of 10â¯nm and exhibited paramagnetic property which is a prerequisite for a positive MRI contrast agent. The longitudinal magnetic relaxivity, r1 of C@ZVI was 4.93â¯mM-1s-1 which is much higher than that of clinically used Gd based agent, gadoterate meglumine (3.6â¯mM-1s-1). For multimodal imaging of the liver, initially the ZVI nanoparticle was tailored with a highly liver specific polysaccharide pullulan, and later with fluorescent carbon dots (Cdts) facilitating both optical and MR imaging. The magnetic relaxivity was retained in P@ZVI-Cdts for T1 contrast imaging with an r1 value of 3.48â¯mM-1s-1. The in vivo MR angiogram using C@ZVI and the liver targeted MRI and optical imaging using P@ZVI-Cdts were successfully demonstrated proving their potential as MRA contrast agent and a liver specific multimodal imaging agent.
