Chemical Power for Microscopic Robots in Capillaries

TL;DR

This paper evaluates the power capabilities of microscopic robots in capillaries using a numerical model, highlighting how design choices and oxygen availability influence their power output for medical applications.

Contribution

It introduces a numerical model to assess power limits of nanorobots in capillaries, considering oxygen consumption, design features, and tissue effects, advancing nanomedicine design strategies.

Findings

Micron-sized robots can produce tens of picowatts using ambient oxygen.

Onboard oxygen storage enables burst power 100-1000 times higher.

Oxygen depletion and heating effects constrain robot power and safety.

Abstract

The power available to microscopic robots (nanorobots) that oxidize bloodstream glucose while aggregated in circumferential rings on capillary walls is evaluated with a numerical model using axial symmetry and time-averaged release of oxygen from passing red blood cells. Robots about one micron in size can produce up to several tens of picowatts, in steady-state, if they fully use oxygen reaching their surface from the blood plasma. Robots with pumps and tanks for onboard oxygen storage could collect oxygen to support burst power demands two to three orders of magnitude larger. We evaluate effects of oxygen depletion and local heating on surrounding tissue. These results give the power constraints when robots rely entirely on ambient available oxygen and identify aspects of the robot design significantly affecting available power. More generally, our numerical model provides an approach to evaluating robot design choices for nanomedicine treatments in and near capillaries.