Acquisition, Processing and Analysis of Electrocardiogram in Awake Zebrafish

Long-term monitoring of intrinsic electrocardiogram (ECG) in zebrafish plays a crucial role in heart disease studies and drug screening. In this paper, we developed a polymer-based apparatus with embedded flexible thin-film electrodes to acquire ECG signals of awake zebrafish. The apparatus was made of polydimethylsiloxane using the molding technique with molds formed by 3D printing. A graphical user interface was built in National Instruments LabView platform for real-time recording, processing, and analysis. The program provided important features, such as signal de-noising, characteristic wave detection, and anomaly detection. Further, it could operate on both real-time coming signals and previously-saved data, facilitating analysis and interpretation. We demonstrated the use of our system to investigate the effects of the anesthetic drug, namely Tricaine (MS-222), on cardiac electrophysiology of zebrafish, revealing promising findings. We speculate that our novel system may contribute to a host of studies in various disciplines using the zebrafish model.