The Roper laboratory develops new methods and techniques in order to investigate biological signaling. Our main biological interest is how the secretion and coupling of islets of Langerhans contribute to proper glucose clearance in the body. The reason why we are interested in the biology of glucose handling is that defects in this process are associated with metabolic diseases, such as type 2 diabetes.
We have developed multiplexed electrophoretic immunoassays to simultaneously measure the release of insulin, glucagon, and islet amyloid polypeptide from islets of Langerhans. We are now incorporating these assays on microfluidic devices using novel optical detection tools to increase the temporal resolution of peptide release. Our research continues to explore and develop new separation and spectroscopic methods for measurement of peptide secretion.
To investigate how the numerous islets within a pancreas can synchronize their output to produce pulses of hormones in the bloodstream, we are developing microfluidic devices that produce complex temporal gradients of stimulants. These waveforms are delivered to populations of islets to test their ability to synchronize. We are developing new microfluidic systems capable of co-culturing different cell types to investigate the roles of cell-cell signaling in synchronization.
Other projects in the lab are ongoing and include the use of finite element analysis to model microfluidic devices and biological cells, interfacing digital microfluidic devices, synthetic reactions within microfluidic devices, and infrared-mediated PCR amplification of DNA.
Mukhitov, N.; Spear, J. M.; Stagg, S. M.; Roper, M. G. "Interfacing microfluidics with negative stain transmission electron microscopy" Analytical Chemistry 2015, DOI: 10.1021/acs.analchem.5b03884.
Roper, M. G. "Cellular analysis using microfluidics" Analytical Chemistry, DOI: 10.1021/acs.analchem.5b04532.
Dhumpa, R.; Truong, T. M.; Wang, X.; Roper, M. G. "Measurement of the entrainment window of islets of Langerhans by microfluidic delivery of a chirped glucose waveform" Integrative Biology 2015, 7:1061-1067.
Wang, X.; Yi, L.; Guillo, C.; Roper, M. G. “Micellar electrokinetic chromatography method for measuring amino acid secretions from islets of Langerhans” Electrophoresis 2015, 36:1172-1178.
Yi, L.; Wang, X.; Dhumpa, R.; Schrell, A. M.; Mukhitov, N.; Roper, M. G. “Integrated perfusion and separation systems for entrainment of insulin secretion from islets of Langerhans” Lab on a Chip 2015, 15, 823-832.