A theory on the instability of tubular membranes to the periodic conformation by laser tweezers.

A mechanical theory to analyze the stability of tubular membranes perturbed by optical tweezers is proposed. I assume that the optical tweezers cause the temporal elevation of hydrostatic pressure inside tubular membranes due to the thermal expansion of solvent water, and I relaxed the conservation of volume per unit length which was strictly maintained in old theories based on the well-known Rayleigh instability. The mechanical energy composed of bending rigidity, interfacial tension, and hydrostatic pressure terms can explain the condition of the previously observed peristaltic and pearling instability. The spontaneous curvature of the membrane is postulated in the theory. The enhanced pressure causes the tubules to enter a peristaltic state with a spinodal line in the phase diagram.