Southern Methodist University View Institution's Website 3 articles published in JoVE Medicine Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice Praveen Kumar1, Man Si1, Kelsey Paulhus1, Edward Glasscock1 1Department of Biological Sciences, Southern Methodist University This protocol aims to describe a new methodology to measure intrinsic cardiac firing rate using microelectrode array recording of the whole sinoatrial node tissue to identify pacemaking defects in mice. Pharmacological agents can also be introduced in this method to study their effects on intrinsic pacemaking. Biochemistry Detergent-free Ultrafast Reconstitution of Membrane Proteins into Lipid Bilayers Using Fusogenic Complementary-charged Proteoliposomes. Mikhail A. Galkin1, Aidan N. Russell2, Steven B. Vik3, Richard M. Berry2, Robert R. Ishmukhametov2 1First Pavlov State Medical University, 2Clarendon Laboratory, Department of Physics, Oxford University, 3Department of Biological Sciences, Southern Methodist University Here we present two ultrafast protocols for reconstitution of membrane proteins into fusogenic proteoliposomes, and fusion of such proteoliposomes with target lipid bilayers for detergent-free delivery of these membrane proteins into the postfusion bilayer. The combination of these approaches enables fast and easily controlled assembly of complex multi-component membrane systems. Engineering Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors Tindaro Ioppolo1, Volkan Ötügen1, Ulas Ayaz1 1Mechanical Engineering Department, Southern Methodist University A high-sensitivity photonic micro sensor was developed for electric field detection. The sensor exploits the optical modes of a dielectric sphere. Changes in the external electric field perturb the sphere morphology leading to shifts in its optical modes. The electric field strength is measured by monitoring these optical shifts.