An infrared heat source for temperature control of a small microscope flow bath

Area of Science:

• Physiology
• Biophysics
• Instrumentation

Background:

• Electrophysiology requires precise control of experimental conditions, including temperature.
• Superfusion baths are commonly used in electrophysiology to maintain cell viability and function.
• Existing heating solutions may be expensive, complex, or lack adequate temperature stability.

Purpose of the Study:

• To describe a simple, inexpensive, and easily installed infrared heat source with temperature control.
• To provide a stable thermal environment for small superfusion baths in electrophysiologic experiments.
• To evaluate the impact of infrared radiation on cardiac cell electrophysiology.

Main Methods:

• Development of a feedback-controlled infrared heating system.
• Utilizing a thermal sensor, amplifier, and feedback circuit to regulate a tungsten/halogen bulb.
• Focusing infrared light onto a superfusion bath and monitoring temperature fluctuations.
• Assessing cardiac action potential duration to detect potential infrared absorption by cells.

Main Results:

• The described system provides accurate temperature control with fluctuations of no more than 0.2 degrees C.
• Good fluid level control was maintained during operation.
• No significant changes in cardiac action potential duration were observed, indicating no preferential absorption of infrared radiation by heart cells.

Conclusions:

• The developed infrared heat source is a practical and effective solution for temperature regulation in electrophysiology.
• The system is cost-effective, easy to install, and maintains stable superfusion bath conditions.
• Infrared radiation does not appear to adversely affect cardiac electrophysiology under these experimental conditions.