|Title:||Assistant Professor / Analytical
Bioanalytical / Biochemistry / Nano / Environmental
|Department of Chemistry and Biochemistry|
Office: GSRC 403A
Hashemi Lab Website
International Society for Monitoring Molecules in Neuroscience
M.Sci., 2003, King's College, London
Ph.D., 2007, Imperial College, London
Honors and Awards
NSF Career Award, 2017; Eli Lilly Young Investigator Award for Analytical Chemistry, 2015; Horiba Award for Analytical Chemistry, 2013.
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.
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”. Just accepted in the Analyst 2016.
Siriwardhane, T. Sulkanen, A. Tremonti, A. McElmurry, S. P. Hashemi, P. “Real-time voltammetric characterization of copper complexation”. Just accepted in Analytical Chemistry 2016. DOI: 10.1021/acs.analchem.6b01312.
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”. Just accepted in Neuron 2016.
Samarnayake, S., Abdalla, A., Robke, R., Nijhout, F., Reed. M., Best. J., Hashemi, P. “A Voltammetric and Mathematical Analysis of Histaminergic Modulation of Serotonin in the Mouse Hypothalamus”. Epub ahead of print in Journal of Neurochemistry 2016. DOI: 10.1111/jnc.13659.
Yang, Y., Ibrahim. A., Hashemi, P., Stockdill, J. “Real-Time, Selective Detection of Copper(II) Using Ionophore-Grafted Carbon-Fiber Microelectrodes”. Epub ahead of print, Analytical Chemistry 2016. DOI: 10.1021/acs.analchem.6b00825.