Cell Membranes Proposed as Source of Electrical Energy via Flexoelectricity
Researchers from the University of Houston and Rutgers University have theoretically proposed that mechanical fluctuations within cell membranes may generate sufficient voltage to power certain biological processes.
These membrane fluctuations are known to be driven by the activity of embedded proteins and the breakdown of adenosine triphosphate (ATP), which is a primary energy carrier in cells. The study, published in PNAS Nexus, provides a theoretical framework suggesting that these membrane movements can produce an electric charge usable by cells.
Mechanism of Flexoelectricity
The proposed mechanism centers on the concept of flexoelectricity, a property where a voltage is produced due to non-uniform strain within a material. Cell membranes are subject to continuous bending caused by thermal fluctuations. While voltage generated from such bending typically cancels out in environments at equilibrium, the researchers posited that the active, non-equilibrium state of living cells could enable a sustained and usable electrical charge.
Calculated Voltage and Biological Implications
Calculations performed by the research team indicate that flexoelectricity could generate a transmembrane electrical potential difference of up to 90 millivolts. This voltage level is considered sufficient to trigger an action potential in a neuron.
The voltage produced by these membrane fluctuations may facilitate the movement of ions, which are charged atoms crucial for electrical and chemical signaling within biological systems. The team estimated that these charges emerge on a millisecond scale, which aligns with the timing of signals observed in nerve cells. The researchers suggest that activity can significantly amplify transmembrane voltage and polarization, indicating a potential physical mechanism for energy harvesting and directed ion transport in living cells.
Broader Significance and Future Research
The findings may also have implications for understanding how coordinated activity across groups of cells could generate larger-scale effects in tissues. Further studies are required to experimentally validate these theoretical predictions within biological systems.
Beyond biological applications, the researchers suggest that the principles of these electricity-producing techniques could inform the design of artificial intelligence networks and synthetic materials inspired by biological systems. They propose that investigating electromechanical dynamics in neuron networks may bridge molecular flexoelectricity with complex information processing, potentially contributing to the understanding of brain function and the development of bio-inspired computational materials.