Abdelrahman Eman Chemistry Department University of Georgia Monday, August 27, 2018 - 11:15am Chemistry Building, Room 400 Inorganic Seminar Cancer is a fatal disease, affecting approximately 25% of the population worldwide1. Given the global impact, early detection of cancer is needed to reduce morbidity and prevent mortality2. Unfortunately, not all forms of cancer diagnosis such as blood tests or biopsy can detect the disease during its early stages. Medical imaging has emerged as one of the salient tools for early detection, but not all imaging modalities fit this criterion. Some modalities either offer low penetration depth or spatial resolution while others use radiation for detection, possibly increasing the burden on cancer patients. Magnetic resonance imaging (MRI) circumvents these issues by using non-invasive magnetic field offering unlimited penetration depth and high resolution3. Additionally, MRI provides contrast but with low sensitivity measured by relaxivity r1, a known stumbling block when it comes to early detection. To overcome low sensitivity, contrast agents such as gadolinium and manganese-based agents are used in conjunction with MRI. Gadolinium has been clinically approved for MRI imaging since the 1980s but suffers from side effects such as brain hypersensitivity, neuronal death and is contraindicated in patients with renal impairment causing nephrogenic systemic failure 4. Given these side effects, manganese based-agents have transpired as an alternative to gadolinium for suffering patients. Although safer for patients, manganese-based agents offer lower r1 values in comparison to gadolinium-based agents, provoking research in improving this value. This talk will focus on enhancing the r1 values of manganese-based agents by doping manganese with different host materials such as Prussian Blue5, clay-like layered double hydroxide6 and hydroxy-apatite7. www.aicr.org/learn-more-about-cancer/infographics/infographics-mortality Etzioni, R.; Urban, N.; Ramsey, S.; McIntosh, M.; Schwartz, S.; Reid, B.; Radich, J.; Anderson, G.; Hartwell, L. Early Detection: The Case for Early Detection. Nat. Rev. Cancer, 2003, 3(4), p.243. Smith, B.R.; Gambhir, S.S. Nanomaterials For In Vivo Imaging. Chem. Rev., 2017, 117(3), p.901-986. Chellan, P.; Sadler, P.J. The Elements of Life and Medicines. Phil. Trans. R. Soc. A, 2015, 373(2037), p.20140182. Cai, X.; Gao, W.; Ma, M.; Wu, M.; Zhang, L.; Zheng, Y.; Chen, H.; Shi, J. A Prussian Blue‐Based Core–Shell Hollow‐Structured Mesoporous Nanoparticle as a Smart Theranostic Agent with Ultrahigh pH‐Responsive Longitudinal Relaxivity. Adv. Mater., 2015, 27(41), p.6382-6389. Li, B.; Gu, Z.; Kurniawan, N.; Chen, W.; Xu, Z.P. Manganese‐Based Layered Double Hydroxide Nanoparticles as a T1‐MRI Contrast Agent with Ultrasensitive pH Response and High Relaxivity. Adv. Mat., 2017, 29(29), p.1700373. Mi, P.; Kokuryo, D.; Cabral, H.; Wu, H.; Terada, Y.; Saga, T.; Aoki, I.; Nishiyama, N.; Kataoka, K. A pH-Activatable Nanoparticle with Signal-Amplification Capabilities for Non-invasive Imaging of Tumour Malignancy. Nat. Nanotech., 2016, 11(8), p.724-730.