David C. Podgorski

Assistant Professor

Headshot_Podgorski_DavidDavid is originally from Virginia Beach, Virginia. After receiving his B.S. in Chemistry from Gardner-Webb University, he completed his Ph.D. in Analytical Chemistry at Florida State University (FSU) under William T. Cooper. David worked as a Postdoctoral Research Assistant under Alan G. Marshall in the Ion Cyclotron Resonance Program at the National High Magnetic Field Laboratory followed by several years as Research Faculty with a joint appointment with the FSU Department of Earth, Ocean, and Atmospheric Sciences. David started as an Assitant Professor at the University of New Orleans Department of Chemistry in 2017.

C. Nacaya Brown

Graduate Student, Ph.D. (Co-Advised by Dr. Matthew A. Tarr)


Nacaya Brown was born in New Orleans and raised in the bay area. She completed her undergraduate degree in chemistry at Xavier University of Louisiana in 2006 and gained industry experience at Folgers, Albermarle and Eurofins Analytical in Petaluma, CA. In Fall 2016, Nacaya returned to the south to be closer to her son and to advance her academic career.  She enrolled in the M.S. program in chemistry at the University of New Orleans where she enjoyed the breeze from the lake, caramel macchiatos, mentorship, and cool science.  With the encouragement of family, faculty, and peers, she applied for entrance into the Ph.D. program.  Following her acceptance in the Spring of 2017, her research focused on drug synthesis and discovery for Glioblastoma treatment.  However, in the Spring of 2018, her research focus shifted from medicinal chemistry to analytical chemistry.

Nacaya is currently a graduate research assistant and conducts analytical research in Tarr and Podgorski laboratories.  Nacaya’s research highlights the impact of sunlight on crude oil emulsification capacity such that factors that control the emulsification of Deepwater Horizon oil are elucidated.  Her findings indicate that the formation of emulsions from oil impact the fate of oil spilled in aquatic environments.  Nacaya hopes that her research will attract opportunities for international travel, skill enrichment, and leadership.

Rana Ghannam

Graduate Student, Ph.D.

Rana Ghannam

Rana was born in Connecticut, but she is originally from Palestine. In 2004, her family decided to move to Amman, Jordan where she spent eight years learning Arabic until she moved back to the United States in 2012. She received her B.S. in Chemistry from the University of New Orleans in May 2019. Rana is currently doing her Ph.D. in Environmental Analytical Chemistry at the University of New Orleans.

Rana’s research in Dr. Podgorski’s lab utilizes laboratory experiments to investigate the fundamental biodegradation pathways of petroleum-derived dissolved organic matter (DOMHC) as a function of chemistry. She uses analytical techniques such as excitation-emission matrix spectroscopy (EEMs) and ultrahigh-resolution mass spectrometry (UHR-MS) to characterize DOMHC, and thus providing knowledge of fundamental relationships between chemical composition and reactivity that can be applied to questions related to the biogeochemical cycling of organic carbon.

Katherine E. Humpal

Graduate Student, Ph.D., Arctic Domain Awarness Centers (ADAC) Fellow

Katherine headshot

Katherine was born and raised on a small farm outside of Protivin, Iowa. She spent 8 years in Air Force Security Forces prior to getting her bachelor’s degree in chemistry with a minor in biology from the University of New Orleans. Currently, Katherine is doing her Ph.D. in Analytical Chemistry with emphasis on environmental chemistry.

Katherine’s research involves the study of the persistence, fate, and effects of hydrocarbon oxidation products (HOPs) that are mobilized in groundwater sources by biogeochemical processes with a primary focus on photooxidation degradation. She has collaborated with individuals from various universities, industries, and government agencies.

Jonathan Long

Graduate Student, Ph.D.

Jonathan LongJonathan’s research focuses on the application of reverse-phase HPLC methods, coupled with size exclusion chromatography methods, in order to separate the complex continuum of dissolved organic matter (DOM) into bins based on core structures and chemistries. The research will ultimately provide insight regarding how the composition of the DOM correlates with its reactivity. This is critical for understanding feedback loops between dissolved organic carbon reservoirs and carbon dioxide in the atmosphere.


Melanie Zareno (Luallen)

Graduate Student, M.S.

Melanie Luallen_2048 (1)Melanie grew up in Orange, CA where she enjoyed going to the beach and playing sports. She attended Azusa Pacific University in Azusa, CA and was a chemist intern at a nanotechnology solutions company before she graduated with a B.S. in Chemistry in 2017. Shortly after graduating, she relocated to Reno, NV for a research assistant position at Charles River Laboratories, a contract research organization leading in global pharmaceutical research. While working a Charles River, Melanie was cross-trained in Formulations and Analytical Chemistry until she worked her way up to a study lead position. As a study lead in Analytical Chemistry, she initiated and organized analyses in pre-clinical studies to test pharmaceutical compounds. Throughout the process of method development/transfer, validation, and toxicology studies, the analytical chemistry department provides data about the drugs including concentration, homogeneity, and stability. After two years at CRL in Reno, Melanie moved to Louisiana in the Spring of 2019 but continued to work remotely for Charles River assisting with study lead responsibilities until the end of 2019. During that time, she started her master’s program in chemistry at UNO and plans to continue her education and career in the analytical field.

Autumn Foret

Undergraduate Student

Autumn ForetAutumn Foret was born and raised in southern Louisiana and found her love for chemistry in high school thanks to her teacher inspiring her. She is an undergraduate student pursuing a degree in Chemistry with a concentration in Biochemistry. After obtaining her bachelor’s degree, she plans on continuing her education and pursuing a doctorate degree in chemistry. In spare time she enjoys painting, reading, and playing various instruments. She adores spending time outside in nature and going to new places for new experiences.


Troy Sbisa

Undergraduate Student

Troy is a double major in both biology and chemistry. His research in the past has dealt with quantifying metabolites in fish tissue using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). He has also researched drug repurposing applications against parasitic nematodes at the University of Massachusetts Medical School. Current research pertains to quantifying polychlorinated biphenyl (PCB) compounds in fish using gas chromatography. His true passion and goal is to help those unable to help themselves, and he believes that his research has given him that opportunity. When Troy is not researching or studying, he spends his time reading, working out, rock climbing, or practicing Brazilian Ju-Jitsu. Troy believes that the research that he does in Dr. David Podgorski’s and Dr. Phoebe Zito’s labs and his future plans of attending Medical School have provided him with many avenues from which he can choose for his life.

Talon Washington

Undergraduate Student, McNair Scholar


Talon was born and raised in New Orleans. She always had a love for science and become interested after watching the Discovery Health Channel on Cable. She currently attends University of New Orleans and majors in Biology. Talon has conducted previous research at Tulane Environmental Science and Public Health and at Ochsner’s Translational Cancer Research lab. At Tulane, she researched how polycyclic aromatic hydrocarbons (PAHs) caused oxidative stress on liver cells. At Ochsner’s lab, she analyzed how T-cells play a role in obesity-linked lupus. She loves research and all the questions it can answer. In addition to answering some questions, she still loves how it can raise more questions than answers sometimes. She hopes to attend a PHD/MD program to become a physician and still conduct research.  Her ultimate goal is to become a pathologist, but knows the best way to practice medicine is through research to better help patients.

Mai B.

High School Student


Mai is a tenth-grade student at Isidore Newman School. After high school, she plans to earn a degree that combines her love of science, the environment, and engineering. Her “Sediment Slurry” machine science project for improving the Louisiana wetlands placed first at both the regional (GNOSEF) and state (LSEF) level while in middle school. She participated in the 2019 Advanced Materials Research Institute (AMRI) research experiences for high school students program at the University of New Orleans which heightened her passion for research.

She is a native New Orleanian who loves her city, the rich culture and history, the food and all it has to offer. She is a talented artist who enjoys poetry, reading, singing and listening to all types of music. In ninth grade, she won the Krewe of Muses cup design contest.


Alumni (Current Information)

Morris Bonton III, M.S. (Eurofins Central Analytical Laboratory)

Jacey Culliford, Undergraduate

Rana Ghannam, Undergraduate Tolmas Scholar (Ph.D. Program, UNO)

Katherine Humpal, Undergraduate Tolmas Scholar (Ph.D. Program, UNO)

Matthew Shields, Undergraduate Tolmas Scholar (M.D. Program, LSU Health)

Terrell Shields, Undergraduate Tolmas Scholar

Minh-Ahn Tran, Undergraduate (U.S. Department of Agriculture)


Visiting International Scientists

Solène Gervais, École nationale supérieure d’ingénieurs de Caen & Centre de Recherche (National Graduate School of Engineering & Research Center)

Lise Chapolon, Instituts universitaires de technologie – Université de Lyon 1 (University Institutes of Technology – University of Lyon 1)