The Casimir Effect in Biology: The Role of Molecular Quantum Electrodynamics in Linear Aggregations of Red Blood Cells

Abstract

Despite the fact that red blood cells carry negative charges, under certain conditions they form cylindrical stacks, or \rouleaux". It is shown here that a form of the Casimir efiect, generalizing the more well-known van der Waals forces, can provide the necessary attractive force to balance the electrostatic repulsion. Erythrocytes in plasma are modelled as negatively charged dielectric disks in an ionic solution, allowing predictions to be made about the conditions under which rouleaux will form. The results show qualitative agreement with observations which suggest that the basic idea is worth further pursuit. In addition to revealing a mechanism which may be widespread in biology at the cellular level, it also suggest new experiments and further applications to other biological systems, colloid chemistry and nanotechnology.