Biopotential

Biopotential refers to the electrical potential difference that exists across the membrane of biological cells. This potential arises primarily from the uneven distribution of ions, such as sodium (Na+), potassium (K+), and chloride (Cl-), between the inside and outside of the cell. These ions are moved across the cell membrane by various ion channels and pumps, creating an electrochemical gradient.

At rest, most cells maintain a negative charge inside relative to the outside, a state known as the resting potential. This resting potential is crucial for cell function, particularly in excitable cells like neurons and muscle cells. When these cells are stimulated, the permeability of their membranes to specific ions changes rapidly, leading to transient alterations in the membrane potential. These changes are called action potentials and are fundamental to processes like nerve impulse transmission and muscle contraction.

The measurement of biopotentials is essential in various biomedical applications. Techniques such as electrocardiography (ECG) for heart activity and electroencephalography (EEG) for brain activity record these electrical signals from the body's surface. These measurements provide valuable diagnostic information about the health of the nervous and cardiovascular systems. Understanding biopotentials is also vital in fields like bioelectronics and the development of prosthetics that can be controlled by muscle signals.