Department of Chemistry

Analytical Chemistry

Research ImageConsistently ranked as one of the top analytical divisions in the United States, ranked number 1 for the fifth year in a row by U.S. News and World Report magazine in its 2011 edition of "America's Best Graduate Schools," the analytical division is recognized as a world leader in this scientific area.

Following the tradition set by the late Professor Charles N. Reilley, the division extends the frontier of the field through a focus on fundamental studies related to chemical analysis and the development of innovative instrumentation. All traditional areas of research are represented, including electrochemistry, mass spectrometry, microscopy, sensors, separations and spectroscopy.

Research projects span a wide range of chemical analysis science and include, but are not limited to, biosensors, nanoscopic materials, neurochemistry, microvolume separations and analysis, protein adsorption, supercritical fluids and single-molecule analysis; for examples of currently active research projects please see the list below. The division has strong relationships with a large number of companies in the pharmaceutical, chemical and scientific instrumentation industries, which provide continued support of research fellowships and the Analytical Seminar series.

 

Recent Research Highlights

Ex Vivo Quantification of PTP

Published in Analytical Chemistry, scientists in the Allbritton Group in collaboration with colleagues from Pharmacology, Biostatistics and Endodontics, and Biomedical Engineering, all at UNC, and the National Health and Environmental Effects Research Laboratory, describe a novel method for the measurement of protein tyrosine phosphatase, PTP, activity in single human airway epithelial cells, hAECs, using capillary electrophoresis.

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Their technique involved the microinjection of a fluorescent phosphopeptide that is hydrolyzed specifically by PTPs. Initial results were then extended to a more physiologically relevant model system: primary hAECs cultured from bronchial brushings of living human subjects. The results demonstrate the utility and applicability of this technique for the ex vivo quantification of PTP activity in small, heterogeneous, human cells and tissues.

 

Colon on a Chip

Crypts are the basic structural and functional units of colonic epithelium and can be isolated from the colon and cultured in vitro into multi-cell spheroids termed "colonoids." Both crypts and colonoids are ideal building blocks for construction of an in vitro tissue model of the colon. In an article published in Lab on a Chip, researchers in the Allbritton Group, describe how they proposed and tested a microengineered platform for capture and in vitro 3D culture of colonic crypts and colonoids.

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The successful formation of viable, multi-cell type colonic tissue on the microengineered platform represents a first step in the building of a "colon-on-a-chip" with the goal of producing the physiologic structure and organ-level function of the colon for controlled experiments.

 

Representative Publications

Dynamics and Evolution of β-Catenin-Dependent Wnt Signaling Revealed through Massively Parallel Clonogenic Screening. Pavak K. Shah, Matthew P. Walker, Christopher E. Sims, Michael B. Major, and Nancy L. Allbritton. Integr. Biol., 2014,6, 673-684.

Small Sample Sorting of Primary Adherent Cells by Automated Micropallet Imaging and Release. Pavak K. Shah, Silvia Gabriela Herrera-Loeza, Christopher E. Sims, Jen Jen Yeh, and Nancy L. Allbritton. Cytometry Part A, Volume 85, Issue 7, pages 642–649, July 2014.

Optimization of 3-D Organotypic Primary Colonic Cultures for Organ-on-Chip Applications. Asad A Ahmad, Yuli Wang, Adam D Gracz, Christopher E Sims, Scott T Magness and Nancy L Allbritton. Journal of Biological Engineering 2014, 8:9.

Immobilization of Lambda Exonuclease onto Polymer Micropillar Arrays for the Solid-Phase Digestion of dsDNAs. Nyoté J. Oliver-Calixte, Franklin I. Uba, Katrina N. Battle, Kumuditha M. Weerakoon-Ratnayake, and Steven A. Soper. Anal. Chem., 2014, 86 (9), pp 4447–4454.

Chemical Vapor Deposition of Aminopropyl Silanes in Microfluidic Channels for Highly Efficient Microchip Capillary Electrophoresis-Electrospray Ionization-Mass Spectrometry. Nicholas G. Batz, J. Scott Mellors, Jean Pierre Alarie, and J. Michael Ramsey. Anal. Chem., 2014, 86 (7), pp 3493–3500.

Micropallet Arrays for the Capture, Isolation and Culture of Circulating Tumor Cells from Whole Blood of Mice Engrafted with Primary Human Pancreatic Adenocarcinoma. Guohua Xu, Yansheng Ye, Xiaoli Liu, Shufen Cao, Qiong Wu, Kai Cheng, Maili Liu, Gary J. Pielak, and Conggang Li. Biosensors and Bioelectronics, Volume 54, 15 April 2014, Pages 476–483.

Fluorous Enzymatic Synthesis of Phosphatidylinositides. Weigang Huang, Angela Proctor, Christopher E. Sims, Nancy L. Allbritton, and Qisheng Zhang. Chem. Commun., 2014,50, 2928-2931.

Response of Single Leukemic Cells to Peptidase Inhibitor Therapy Across Time and Dose Using a Microfluidic Device. Michelle L. Kovarik, Alexandra J. Dickinson, Pourab Roy, Ranjit A. Poonnen, Jason P. Fine and Nancy L. Allbritton. Integr. Biol., 2014, 6, 164-174.

Ex Vivo Chemical Cytometric Analysis of Protein Tyrosine Phosphatase Activity in Single Human Airway Epithelial Cells. Ryan M. Phillips, Lisa A. Dailey, Eric Bair, James M. Samet, and Nancy L. Allbritton. Anal. Chem., 2014, 86 (2), pp 1291–1297.

Capture and 3D Culture of Colonic Crypts and Colonoids in a Microarray Platform. Yuli Wang, Asad A. Ahmad, Pavak K. Shah, Christopher E. Sims, Scott T. Magness and Nancy L. Allbritton. Lab Chip , 2013, 13, 4625-4634.