Abstract

The ultimate goal of nanomedicine is to perform nanorobotic therapeutic procedures on specified individual cells comprising the human body. This paper reports the first theoretical scaling analysis and mission design for a cell repair nanorobot. One conceptually simple form of basic cell repair is chromosome replacement therapy ; in which the entire chromatin content of the nucleus in a living cell is extracted and promptly replaced with a new set of prefabricated chromosomes which have been artificially manufactured as defect-free copies of the originals. The chromallocyte is a hypothetical mobile cell-repair nanorobot capable of limited vascular surface travel into the capillary bed of the targeted tissue or organ; followed by extravasation; histonatation; cytopenetration; and complete chromatin replacement in the nucleus of one target cell; and ending with a return to the bloodstream and subsequent extraction of the device from the body; completing the CRT mission. A single lozenge-shaped 69 micron3 chromallocyte measures 4.18 microns and 3.28 microns along cross-sectional diameters and 5.05 microns in length; typically consuming 50-200 pW in normal operation and a maximum of 1000 pW in brief bursts during outmessaging; the most energy-intensive task. Treatment of an entire large human organ such as a liver; involving CRT on all 250 billion multinucleate hepatic tissue cells; might require the localized infusion of a ~1 terabot ~69 cm3 chromallocyte dose in a 1-liter 7% saline suspension during a ~7 hour course of therapy. Chromallocytes would be the ideal delivery vector for gene therapy.