THE ELECTRIC CAPACITY OF SUSPENSIONS WITH SPECIAL REFERENCE TO BLOOD

Area of Science:

• Electrical Engineering
• Biophysics
• Materials Science

Background:

• Understanding the electrical properties of suspensions is crucial for various scientific and industrial applications.
• Previous models for suspension capacity had limitations in accurately describing complex particle structures.

Purpose of the Study:

• To develop and validate a theoretical model for the specific capacity of suspensions, particularly those with structured particles like red blood cells.
• To experimentally measure suspension capacity over a wide frequency range and determine key physical parameters of suspended particles.

Main Methods:

• A specialized bridge and substitution method were employed to measure suspension capacity between 800 Hz and 4.5 MHz.
• Measurements were conducted on suspensions of dog red blood cells with varying volume concentrations.
• The suspending liquid was adjusted to match the specific resistance of the suspension for accurate comparisons.

Main Results:

• A formula was derived and validated for the specific capacity of suspensions, applicable to various particle shapes.
• The static capacity of the corpuscle membrane (C(o)) was found to be independent of frequency (up to 4.5 MHz) and suspending liquid.
• The calculated membrane thickness of red blood cells was determined to be 3.3 x 10^-7 cm.

Conclusions:

• The experimental results strongly support the theoretical model for suspension capacity.
• The findings confirm that C(o) represents the static capacity of the corpuscle membrane, providing insights into its electrical properties.
• The calculated membrane thickness offers valuable quantitative data for biophysical studies.