Potentiometric dyes are used to image spatial/temporal patterns of electrical activity in cells and tissues. This laboratory has been actively engaged in the development of this technology for the membrane potential imaging of both excitable and non-excitable systems. Sensing voltage in excitable cells or tissues is more challenging because it requires that the dye respond to voltage changes with Our aims i n this proposal are to tune the dyes to take best advantage of these laser-based modalities and to customize the dyes for applications in neuroscience and cardiac electrophysiology.
The first Aim i s to synthesize potentiometric indicators with improved photostability. This will, of course, be of general benefit to experimentalists, enabling them to extend the duration of optical recording measurements and minimize photodynamic damage to the biological preparation. More specifically, it will allow for the use of narrow band emission collection to maximize the sensitivity of the measurement during intense laser illumination.
The second Aim i s to determine the mechanism(s) by which the SHG signal from dye-stained membranes is sensitive to membrane potential. This will allow us to more rationally design new dyes that can produce large SHG responses with sufficient speed to measure action potentials. In the third Aim, we will apply these new technologies to the study of electrical signals in single spines in cerebellar Purkinje cells. In addition to providing a great test bed for the dye technologies, these studies will explore the fundamental question of whether a spine can compartmentalize electrical inputs. Depolarizations restricted to Purkinje spines would have important consequences for our understanding of synaptic plasticity in these neurons. In our fourth Aim, we will engage in a variety of collaborations with cardiologist and neuroscientists to develop customized dyes and methods for their experimental needs. We will also continue to supply dyes that are not commercially available to the optical recording community.

Public Health Relevance

This project will develop new functional contrast agents that will permit the imaging of electrical activity in excitable tissue with sub-cellular resolution. This technology will be applied to the study of normal and diseased heart. It will also be used to understand information processing in the brain at the level of a single synapse.

National Institute of Health (NIH)
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Research Project (R01)
Project #
Application #
Study Section
Microscopic Imaging Study Section (MI)
Program Officer
Conroy, Richard
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Connecticut
Schools of Medicine
United States
Zip Code
Lee, Peter; Calvo, Conrado J; Alfonso-Almazán, José M et al. (2017) Low-Cost Optical Mapping Systems for Panoramic Imaging of Complex Arrhythmias and Drug-Action in Translational Heart Models. Sci Rep 7:43217
Geiss, Andreas F; Khandelwal, Raghav; Baurecht, Dieter et al. (2017) pH and Potential Transients of the bc1 Complex Co-Reconstituted in Proteo-Lipobeads with the Reaction Center from Rb. sphaeroides. J Phys Chem B 121:143-152
Zhang, Haichong K; Yan, Ping; Kang, Jeeun et al. (2017) Listening to membrane potential: photoacoustic voltage-sensitive dye recording. J Biomed Opt 22:45006
Acker, Corey D; Hoyos, Erika; Loew, Leslie M (2016) EPSPs Measured in Proximal Dendritic Spines of Cortical Pyramidal Neurons. eNeuro 3:
Crocini, Claudia; Ferrantini, Cecilia; Coppini, Raffaele et al. (2016) Optogenetics design of mechanistically-based stimulation patterns for cardiac defibrillation. Sci Rep 6:35628
Crocini, C; Ferrantini, C; Scardigli, M et al. (2016) Novel insights on the relationship between T-tubular defects and contractile dysfunction in a mouse model of hypertrophic cardiomyopathy. J Mol Cell Cardiol 91:42-51
Crocini, Claudia; Coppini, Raffaele; Ferrantini, Cecilia et al. (2016) T-Tubular Electrical Defects Contribute to Blunted ?-Adrenergic Response in Heart Failure. Int J Mol Sci 17:
Frank, Pinar; Siebenhofer, Bernhard; Hanzer, Theresa et al. (2015) Proteo-lipobeads for the oriented encapsulation of membrane proteins. Soft Matter 11:2906-2908
Brown, Sherry-Ann; McCullough, Louise D; Loew, Leslie M (2015) Computational neurobiology is a useful tool in translational neurology: the example of ataxia. Front Neurosci 9:1
Loew, Leslie M (2015) Design and Use of Organic Voltage Sensitive Dyes. Adv Exp Med Biol 859:27-53

Showing the most recent 10 out of 46 publications