@article {20044,
	title = {Manganese dioxide-based nano/microreactors for long-term MRI imaging and Reactive Oxygen Species scavenging},
	journal = {TERMSTEM 2019 Conference},
	year = {2019},
	month = {2019-11-06 00:00:00},
	address = {Braga, Portugal},
	abstract = {<p>In a healthy brain, manganese (Mn<sup>2+</sup>) ions can enter excitable cells and circulate within axons and across synapses. Because these ions can also be used as a contrast agent, Manganese Enhanced Magnetic Imaging (MEMRI) has been used, not only to study Amyotrophic Lateral Sclerosis (ALS), but also to guide intrathecal drug/cell delivery [1]. Mn<sup>2+</sup> ions allow long-term T1-weigthed imaging, representing an advantage when compared to other ions. In ALS, motor neuron degeneration occurs and it has been correlated with oxidative stress, which can potentially be a therapeutic target [1]. Previous work [2] has demonstrated the ability of manganese dioxide (MnO<sub>2</sub>) nanoparticles to scavenge Reactive Oxygen Species (ROS) by breaking down hydrogen peroxide in water, oxygen and Mn<sup>2+</sup>. As MnO<sub>2</sub> nanoparticles present toxicity when administered in high doses, it is our goal to develop MnO<sub>2</sub> nano/microreactors, where MnO<sub>2</sub> nanoparticles will be blended with a methacrylated gellan-gum (GG-MA) matrix. These nano/microreactors will potentially be used, not only to regulate apoptosis and inflammation in tissues, but also to be delivered and guided by MRI. GG-MA was selected due to its affinity to Mn<sup>2+</sup>, biocompatibility, biodegradability, easy functionalization and similarity to the extracellular matrix [3]. GG-MA was synthesized according to a previously described protocol [4] and further characterized via FTIR and <sup>1</sup>H-NMR. A comparison between synthetized and commercially bought MnO<sub>2</sub> nanoparticles will also be performed. Nano/microreactors will be evaluated regarding their rheology, stability, permeability and morphology. Their effect on cell viability and ability to scavenge ROS will also be evaluated.</p>},
	keywords = {GG-MA, MnO2 nano/microreactors, MRI imaging, ROS scavenging},
	author = {Lopes, S. V. and Oliveira, E. P. and Reis, R. L. and Silva-Correia, J. and Oliveira, J. M.}
}
