Education

M.Sci., 2003, King's College, London
Ph.D., 2007, Imperial College, London

Honors and Awards

USC Breakthrough Stars Award, 2018; Society of Pittsburgh Chemists Pittcon Achievement Award, 2018; Society for Electroanalytical Chemistry (SEAC) Royce W. Murray Award, 2018; NSF Career Award, 2017; Eli Lilly Young Investigator Award for Analytical Chemistry, 2015; Horiba Award for Analytical Chemistry, 2013.

Research Interests

Real-time Quantitative Neurotransmitter Measurements:  We are developing cutting-edge electrochemical technology to monitor the brain's molecules in intact brains in real time.  Of particular interest to us are the neurotransmitters serotonin and histamine.  Serotonin and histamine dysfunction are thought to underlie a variety of diseases including mood and emotional disorders and neurodegenerative diseases.  Depression is a debilitating mental disorder that affects 12% of the US population. We are interested in the in vivo dynamics of serotonin and histamine in healthy and depressed subjects.  We are also seeking to understand the effect of antidepressants on the levels of these two molecules.  An acute antidepressant dose causes large deviation in brain serotonin and histamine, however relief from depression symptoms often comes only after a chronic treatment period.  Moreover, when antidepressants are prescribed to patients, they have variable clinical effectiveness.  We are studying these phenomena by developing novel electrochemical tools including fast scan cyclic voltammetry (FSCV) at carbon fiber microelectrodes (CFMs) and combining them with optogenetics, two – photon imaging, mathematical modeling an animal behavior.

Trace Metal Speciation Sensors:  Trace metals play important roles in biological and environmental processes.  Trace metal contamination can be extremely harmful to natural water systems, which negatively impacts the ecosystem and human health.  To understand trace metal transport and mobilization, it is important to measure metal speciation during rapid environmental events (such as storms).  We have developed FSCV at CFMs to measure trace metal (such as copper, lead and arsenic) speciation in real time.  We are working with environmental engineers to understand the kinetic properties of trace metal speciation in local water and soil samples.

 Selected Publications

Best, J., Nijhout, S., Samarnayake, S., Hashemi, P., Reed, M. C. “A Mathematical Model for Histamine Synthesis, Release, and Control in Varicosities”. Theoretical Biology and Medical Modeling 2017, 12:14(1), 24. DOI: 10.1186/s12976-017-0070-9.

Abdalla, A., Atcherley, C., Qiang, B., Pena, E., Morgan, S., Heien, M., Hashemi, P. “In Vivo Ambient Serotonin Measurements at Carbon Fiber Microelectrodes”. Analytical Chemistry 2017, 19;89(18), 9703-9711. DOI: 10.1021/acs.analchem.7b01257.

Yi, W, Yang, Y, Hashemi, P., Cheng, M. “3D Carbon Nanofibers Fabricated by Plasma-Assisted Pyrolysis for Enhancing Sensitivity and Stability During Real-time Dopamine Detection”. Biomedical Microdevices 2016, 18(6), 112. DOI: 10.1007/s10544-016-0136-1.

Pathirathna, P., Siriwardhane, T., McElmurry, S. P., Morgan, S., Hashemi, P. “Fast Voltammetry of Metals at Carbon Fiber Microelectrodes: Ultra Rapid Determination of Solution Formation Constants”. Analyst  2016, 141(23), 6432-6437. DOI: 10.1039/C6AN01807F.

Jin, Y., Wood, K. M., Sun, L., Cudmore, R., Abdalla, A., Kannan, G., Pletnikov, M., Hashemi, P., Linden, D. “Long-distance Regeneration of Serotonin Axons in the Adult Mouse Brain”. Neuron 2016, 91(4), 748-62. DOI: 10.1016/j.neuron.2016.07.024.