Multiplexed Fiber-Optic Fluorescence for Functional Monitoring of Perfused Hearts

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Spectroscopy

Background:

• Monitoring cardiac molecular dynamics is crucial for understanding heart function and disease.
• Current methods may lack real-time, noninvasive capabilities for comprehensive assessment.

Purpose of the Study:

• To develop and validate a multiexcitation, ratiometric fiber-optic spectroscopic platform for real-time cardiac monitoring.
• To enable noninvasive assessment of biochemical and physiological processes in isolated rat hearts.

Main Methods:

• Utilized a fiber-optic balloon probe for concurrent optical measurements and pressure sensing.
• Employed multiedge bandpass filters for parallel fluorescence spectroscopy of endogenous and exogenous fluorophores.
• Applied multivariate regression analysis and a ratiometric approach with paired agents to quantify fluorophore concentrations and mitigate artifacts.

Main Results:

• Successfully demonstrated accurate quantification of fluorophore concentrations.
• Validated the system's capability using tetramethylrhodamine ethyl ester (TMRE) to assess mitochondrial membrane potential.
• Extracted physiologically relevant metrics, showcasing sensitive assessment of cardiac function.

Conclusions:

• The developed platform provides a versatile tool for real-time, noninvasive monitoring of cardiac molecular dynamics.
• It facilitates comprehensive assessment of cardiac biochemical and functional status.
• Shows potential for investigating novel fluorescent probes in cardiac research.