TY - JOUR
T1 - Fluorescence Imaging of Electrical Activity in Cardiac Cells Using An All-Solid-State System
AU - Entcheva, Emilia
AU - Kostov, Yordan
AU - Tchernev, Elko
AU - Tung, Leslie
N1 - Funding Information:
Manuscript received October 30, 2002; revised June 8, 2003. The work of E. Entcheva was supported in part by the American Heart Association (Mid-Atlantic Affiliate) through Postdoctoral Fellowship 9920393U. The work of L. Tung was supported in part by the National Institutes of Health (NIH) under Grant HL48266 and Grant HL66239. Asterisk indicates corresponding author. *E. Entcheva was with the Department of Biomedical Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21250 USA. She is now with the Department of Biomedical Engineering, State University of New York at Stony Brook, HSC T18-030, Stony Brook, NY 11794-8181 USA (e-mail: email: emilia.entcheva@sunysb.edu).
PY - 2004/2
Y1 - 2004/2
N2 - Tracking spatial and temporal determinants of cardiac arrhythmogenesis at the cellular level presents challenges to the optical mapping techniques employed. In this paper, we describe a compact system combining two nontraditional low-cost solutions for excitation light sources and emission filters in fluorescence measurements of transmembrane potentials, V m, or intracellular calcium, [Ca2+]i in cardiac cell networks. This is the first reported use of high-power blue and green light emitting diodes (LEDs), to excite cell monolayers stained with Vm- (di-8-ANEPPS) or [Ca2+]i - (Fluo-3) sensitive dyes. In addition, we use simple techniques for fabrication of suitable thin emission filters with uniform properties, no auto-fluorescence, high durability and good flexibility for imaging Vm or [Ca 2+]i. The battery-operated LEDs and the fabricated emission filters, integrated with a fiber-optic system for contact fluorescence imaging, were used as tools to characterize conduction velocity restitution at the macro-scale. The versatility of the LEDs for illumination is further emphasized through 1) demonstration of their usage for epi-illumination recordings at the single-cell level, and 2) demonstration of their unique high-frequency light modulation ability. The LEDs showed excellent stability as excitation light sources for fluorescence measurements; acceptable signal-to-noise ratio and negligible cell photodamage and indicator dye photobleaching were observed.
AB - Tracking spatial and temporal determinants of cardiac arrhythmogenesis at the cellular level presents challenges to the optical mapping techniques employed. In this paper, we describe a compact system combining two nontraditional low-cost solutions for excitation light sources and emission filters in fluorescence measurements of transmembrane potentials, V m, or intracellular calcium, [Ca2+]i in cardiac cell networks. This is the first reported use of high-power blue and green light emitting diodes (LEDs), to excite cell monolayers stained with Vm- (di-8-ANEPPS) or [Ca2+]i - (Fluo-3) sensitive dyes. In addition, we use simple techniques for fabrication of suitable thin emission filters with uniform properties, no auto-fluorescence, high durability and good flexibility for imaging Vm or [Ca 2+]i. The battery-operated LEDs and the fabricated emission filters, integrated with a fiber-optic system for contact fluorescence imaging, were used as tools to characterize conduction velocity restitution at the macro-scale. The versatility of the LEDs for illumination is further emphasized through 1) demonstration of their usage for epi-illumination recordings at the single-cell level, and 2) demonstration of their unique high-frequency light modulation ability. The LEDs showed excellent stability as excitation light sources for fluorescence measurements; acceptable signal-to-noise ratio and negligible cell photodamage and indicator dye photobleaching were observed.
KW - Calcium
KW - Cultured cardiac cells
KW - LED excitation
KW - Optical mapping
KW - Voltage-sensitive dyes
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U2 - 10.1109/TBME.2003.820376
DO - 10.1109/TBME.2003.820376
M3 - Article
C2 - 14765706
AN - SCOPUS:1642580802
SN - 0018-9294
VL - 51
SP - 333
EP - 341
JO - IEEE Transactions on Biomedical Engineering
JF - IEEE Transactions on Biomedical Engineering
IS - 2
ER -