© 1999 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Nanomedicine, Volume I: Basic Capabilities, Landes Bioscience, Georgetown, TX, 1999

9.4 In Vivo Locomotion

One of the most important basic capabilities a medical nanorobot may possess is the ability to move about inside the human body. At its most simple, this movement may be purely statistical, with nanodevices carried along with the natural ebb and flow of bodily fluids. At the other extreme, nanorobot locomotion may be highly deterministic, including powered drive mechanisms, mapping and active navigation, and traverses of diverse histological territories having markedly different mechanical and chemical characteristics. The subject matter is huge and quite impossible to cover fully in a single Chapter. As a result, the discussion here is merely a preliminary survey of the most important issues and challenges of in vivo locomotion, suggesting promising new areas for future research.

Section 9.4.1 opens with an overview of fluid viscosity generally and the rheology (flow characteristics) of nanorobot-rich biofluids that might be associated with passive nanorobot locomotion. Aspects and techniques of active swimming through the bloodstream, or sanguinatation, are described in Section 9.4.2. This is followed by discussions of cytoambulation (cell surface walking and anchoring) in Section 9.4.3, histonatation (tissue diving including diapedesis, ECM transit, and intercellular passage) in Section 9.4.4, cytopenetration (entering individual cells) in Section 9.4.5, locomotion inside the cell (Section 9.4.6), and finally cytocarriage (nanorobotic pilotage of natural motile cells) in Section 9.4.7. The biocompatibility of motive mechanisms is discussed in Chapter 15.

Last updated on 21 February 2003