A Theoretical Model of a Molecular-Motor-Powered Pump

Abstract

The motion of a cylindrical bead in a fluid contained within a two-dimensional channel is investigated using the boundary element method as a model of a biomolecular-motor-powered microfluidics pump. The novelty of the pump lies in the use of motor proteins (kinesin) to power the bead motion and the few moving parts comprising the pump. The performance and feasibility of this pump design is investigated using two model geometries: a straight channel, and a curved channel with two concentric circular walls. In the straight channel geometry, it is shown that increasing the bead radius relative to the channel width, increases the flow rate at the expense of increasing the force the kinesins must generate in order to move the bead. Pump efficiency is generally higher for larger bead radii, and larger beads can support higher imposed loads. In the circular channel geometry, it is shown that bead rotation modifies the force required to move the bead and that shifting the bead inward slightly reduces the required force. Bead rotation has a minimal effect on flow rate. Recirculation regions, which can develop between the bead and the channel walls, influence the stresses and force on the bead. These results suggest this pump design is feasible, and the kinesin molecules provide sufficient force to deliver pico- to atto- l/s flows.

A boundary element model of the transport of a semi-infinite bubble through a microvessel bifurcation

“…[34][35][36] We use quadratic elements to compute the integrals in Eq. [34][35][36] We use quadratic elements to compute the integrals in Eq.…”

Chemically Powered Micro‐ and Nanomotors

“…[18] They can be used as nano-biosensors [19] and nanoscale probes to examine surfaces, and have been suggested as nanofluidic pumps (Figure 1 A). [20] Swarms of "molecular shuttles" have also been observed to modify the diffusion flows in nanofluidic devices. [21] Single enzymes such as urease can act as nanomotors, as indicated by an enhancement in the diffusion coefficient in Lluís Soler was born in Terrassa (Spain) in 1979.…”

Engineering Applications of Biomolecular Motors

“…For example, biomolecular motors can in principle be used to construct a microscopic displacement pump (49) for the purpose of moving analyte molecules through a microfluidic system. However, biomolecular motors can also act orthogonally to fluid flow, for example by capturing analytes and extracting them from a fluid stream molecule by molecule (50).…”

“…A theoretical analysis suggests the feasibility of a pump design relying on a kinesin-coated microsphere moving in a slightly larger microchannel decorated with aligned microtubules (Figure 10) (49). The motor-driven transport of the microsphere could deliver flows in the atto-to picoliter per second range.…”