Bhavesh, RijuLechuga-Vieco, Ana V.Ruiz-Cabello, JesusHerranz, Fernando2017-10-302017-10-302015Nanomaterials. 2015; 5(4):1880-902079-4991http://hdl.handle.net/20.500.12105/5255Iron oxide nanoparticles have long been studied as a T-2 contrast agent in MRI due to their superparamagnetic behavior. T-1-based positive contrast, being much more favorable for clinical application due to brighter and more accurate signaling is, however, still limited to gadolinium- or manganese-based imaging tools. Though being the only available commercial positive-contrast agents, they lack an efficient argument when it comes to biological toxicity and their circulatory half-life in blood. The need arises to design a biocompatible contrast agent with a scope for easy surface functionalization for long circulation in blood and/or targeted imaging. We hereby propose an extremely fast microwave synthesis for fluorescein-labeled extremely-small iron oxide nanoparticles (fdIONP), in a single step, as a viable tool for cell labeling and T-1-MRI. We demonstrate the capabilities of such an approach through high-quality magnetic resonance angiographic images of mice.engVoRhttp://creativecommons.org/licenses/by/4.0/iron oxide nanoparticlesMRIT-1 contrastMicrowaveMRI CONTRAST AGENTSMAGNETIC NANOPARTICLEST-1Atribución 4.0 Internacional2834710151880-189010.3390/nano5041880Nanomaterialsopen access