Bioanalytical Chemistry: Novel microanalytical tools for studying fundamentals of glucose homeostasis and diabetes.
The Easley laboratory is focused on the development of novel microanalytical techniques that allow us to perform unique experiments on biological systems. One major focus of our laboratory involves the development of microfluidic methods to study secretions from small numbers of cells in the form of intact, primary tissue. We are interested in the consequences of cellular architecture in paracrine signaling within pancreatic islets of Langerhans, the functional units of insulin secretion that help to maintain blood glucose homeostasis. Since it is now understood that adipose tissue (fat) is an active endocrine organ, we are also using microfluidics to help measure rapid secretion from primary adipocytes (fat cells). These methods should help improve our understanding of hormone secretion from adipose tissue. Debilitating conditions such as diabetes, obesity, and metabolic syndrome are fundamentally linked to these types of tissue. The second major focus in our lab is to utilize DNA-antibody conjugates and DNA aptamers in cooperative sensing approaches, allowing picomolar detection limits of protein and small molecule analytes from small volumes of sample. Concurrently, we are developing cooperative methods to select DNA aptamers for high affinity and specificity in target binding.
Research in our laboratory spans several scientific disciplines, from fundamental analytical chemistry to molecular and cellular biology, conducted through combinations of novel and traditional techniques: microfluidics, fluorescence microscopy and spectroscopy, passive flow control, molecular biology, aptamer selection, and electrophoresis. Please visit our RESEARCH WEB PAGE for more details.
Li, X.; Brooks, J. C.; Hu, J.; Ford, K. I.; Easley, C. J.* "3D-templated, fully automated microfluidic input/output multiplexer for endocrine tissue culture and secretion sampling," Lab Chip 2017, DOI: 10.1039/C6LC01201A. PDF
Brooks, J. C.; Judd, R. L.; Easley, C. J.* “Culture and Sampling of Primary Adipose Tissue in Practical Microfluidic Systems,” in Methods in Molecular Biology: Thermogenic Fat - Methods and Protocols, Humana Press/Springer (New York) 2017, in press, DOI: 10.1007/978-1-4939-6820-6_18.
Brooks, J. C.; Ford, K. I.; Holder, D. H.; Holtan, M. D.; Easley, C. J.* "Macro-to-micro interfacing to microfluidic channels using 3D-printed templates: Application to time-resolved secretion sampling of endocrine tissue," Analyst 2016, 141, 5714-5721. PDF
Kerscher, P.; Turnbull, I. C.; Hodge, A. J.; Kim, J.; Seliktar, D.; Easley, C. J.; Costa, K. D.; Lipke, E.* "Direct Hydrogel Encapsulation of Pluripotent Stem Cells Enables Ontomimetic Differentiation and Growth of Engineered Human Heart Tissues," Biomaterials 2016, 83, 383-395. PDF
Kim, J.; Hu, J.; Bezerra, A. B.; Holtan, M. D.; Brooks, J. C.; Easley, C. J.* "Protein Quantification using Controlled DNA Melting Transitions in Bivalent Probe Assemblies," Anal. Chem. 2015, 87, 9576–9579. PDF
Hu, J.; Kim, J.; Easley, C. J.* "Quantifying Aptamer-Protein Binding via Thermofluorimetric Analysis," Anal. Methods 2015, 7, 7358-7362. PDF
- Dr. Easley featured in "Emerging Investigators" issue (Link)
Godwin, L. A.; Brooks, J. C.; Hoepfner, L. D.; Wanders, D.; Judd, R. L.; Easley, C. J.* "A Microfluidic Interface Design for the Culture and Sampling of Adiponectin from Primary Adipocytes," Analyst 2015, 140, 1019-1025. PDF
- Selected as Cover Article
- Featured as Analyst Hot Article
Hu, J.; Yu, Y.; Brooks, J. C.; Godwin, L. A.; Somasundaram, S.; Torabinejad, F.; Kim, J.; Shannon, C.*; Easley, C. J.* "A Reusable Electrochemical Proximity Assay for Highly Selective, Real-Time Protein Quantitation in Biological Matrices," J. Am. Chem. Soc. 2014, 136, 8467-8474. PDF
DeJournette, C. J.; Kim, J.; Medlen, H.; Li, X.; Vincent, L. J.; Easley, C. J. "Creating Biocompatible Oil-Water Interfaces without Synthesis: Direct Interactions between Primary Amines and Carboxylated Perfluorocarbon Surfactants." Anal. Chem. 2013, 85, 10556-10564. PDF
Godwin, L. A.; Deal, K. S.; Hoepfner, L. D.; Jackson, L. C.; Easley, C. J. "Measurement of Microchannel Fluidic Resistance with a Standard Voltage Meter." Anal. Chim. Acta 2013, 758, 101-107. PDF
Hu, J.; Wang, T.; Kim, J.; Shannon, C.; Easley, C. J. "Quantitation of femtomolar protein levels via direct readout with the electrochemical proximity assay." J. Am. Chem. Soc. 2012, 134, 7066–7072. PDF
Horn, D. W.; Tracy, K. P.; Easley, C. J.; Davis, V. A. "Lysozyme Dispersed Single-Walled Carbon Nanotubes: Interaction and Activity." J. Phys. Chem. C 2012, 116, 10341–10348. PDF
Deal, K. S. and Easley, C. J. "Self-Regulated, Droplet-Based Sample Chopper for Microfluidic Absorbance Detection." Analytical Chemistry 2012, 84, 1510–1516. PDF
Godwin, L. A.; Pilkerton, M. E.; Deal, K. S.; Wanders, D.; Judd, R. L.; Easley, C. J. "A passively operated microfluidic device for stimulation and secretion sampling of single pancreatic islets." Analytical Chemistry,2011, 83, 7166–7172. PDF
Hu, J. and Easley, C. J. "A Simple and Rapid Approach for Measurement of Dissociation Constants of DNA Aptamers against Proteins and Small Molecules via Automated Microchip Electrophoresis." Analyst, 2011, 136, 3461-3468. PDF
Kim, J.; Hu, J.; Sollie, R. S.; Easley, C. J. "Improvement of sensitivity and dynamic range in proximity ligation assays by asymmetric connector hybridization." Analytical Chemistry, 2010, 82, 6976-6982. PDF
Easley, C. J.; Rocheleau, J. V.; Head, W. S.; Piston, D. W. “Quantitative measurement of zinc secretion from single pancreatic islets with high temporal resolution using droplet-based microfluidics.” Analytical Chemistry, 2009, 81, 9086. PDF
- Full-page Research Profile by Nancy Lamontagne
Leslie, D. C; Easley, C. J.; Seker, E.; Karlinsey, J. M.; Utz, M.; Begley, M. R.; Landers, J. P. “Frequency-specific flow control in microfluidic circuits with passive elastomeric features.” Nature Physics, 2009, 5, 231. PDF
- Editors' Choice, Science, 2009, 23, 1539. PDF
- Research Highlight, Lab on a Chip, 2009, 9, 861. PDF
Easley, C. J.; Benninger, R. K. P.; Shaver, J. H.; Head, W. S.; Piston, D. W. “Rapid and inexpensive fabrication of polymeric microfluidic devices via toner transfer masking.” Lab on a Chip, 2009, 9, 1119-1127. PDF
- Research Highlight, Nature Methods, 2009, 6, 194. PDF
Mao, S.; Benninger, R. K. P.; Jackson, D.; Yan, Y.; Petchprayoon, C.; Jackson, D. K.; Easley, C. J.; Piston, D. W.; Marriott, G. “Optical lock-in detection of fluorescence resonance energy transfer using synthetic and genetically-encoded optical switches.” Biophysical Journal, 2008, 94, 4515-4524. PDF
Easley, C. J.; Karlinsey, J. M.; Bienvenue, J. P.; Legendre, L. A.; Roper, M. G.; Feldman, S. H.; Hughes, M. A.; Hewlett, E. L.; Merkel, T. J.; Ferrance, J. P.; Landers, J. P. “A fully-integrated microfluidic genetic analysis system with sample in-answer out capability.” Proc. Natl. Acad. Sci. USA, 2006, 103, 19272-19277. PDF
- Editors' Choice, Science, 2007, 315, 5810.
- Research Highlight, Nature Biotechnology, 2007, 25, 69.
- Bio Sphere, Analytical Chemistry, 2007, 79, 809.