This document proposes using nanotechnology to create artificial red blood cells, called respirocytes, that could deliver more oxygen to tissues than natural red blood cells. Respirocytes would be spherical, 1 micron vessels containing oxygen, carbon dioxide, and ballast water storage tanks, sensors, and a nanocomputer. An onboard fuel cell would power molecular sorting rotors and subsystems using glucose and oxygen. Each respirocyte could store and deliver all of its oxygen, replacing the need for 5.36 trillion natural red blood cells to fully duplicate blood's oxygen capacity. Respirocytes could temporarily replace lost red blood cells in emergencies and also treat various forms of anemia.
2. Nanotechnology is defined as the fabrication of devices with
precision to the scale of 1 to 100 nanometers (nm)
This scale yields precision on the atomic or molecular scale
Nanotechnology is also referred to as molecular
manufacturing
Nanotechnology has the potential for a nearly limitless
number of applications in a wide range of fields such as
physics, biology, engineering, chemistry, and computer
science
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4. • The artificial red blood cell or Respirocyte
• Proposed here is a blood borne spherical 1-micron
diamondoid 1000-atm pressure vessel
• An onboard nanocomputer and numerous chemical and
pressure sensors enable complex device behaviours remotely
reprogrammable by the physician via externally applied
acoustic signals
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With active pumping powered by endogenous serum glucose, able to
deliver 236 times more oxygen to the tissues per unit volume than
natural red cells and to manage carbonic acidity
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• There are three main storage tank - one for oxygen , another
for carbon dioxide and third for ballast water
• An onboard chemo mechanical turbine or fuel cell generates
power by combining glucose drawn from the bloodstream and
oxygen drawn from internal storage
• This is converted to mechanical power which drives molecular
sorting rotors and other subsystems, as demonstrated in
principle by a variety of biological motor systems such as
bacteria flagella
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• Each power plant develops 0.3 Pico watts of power
• That's enough energy to fill the oxygen tank in 10 seconds
from empty, a pumping rate of 100 million molecules/sec
• The average male human body has 28.5 trillion red blood
cells, each containing 270 million hemoglobin molecules
binding four O2 molecules per hemoglobin
• However, since hemoglobin normally operates between 95%
saturation (arterial) and 70% saturation (venous), only 25% of
stored oxygen is accessible to the tissues
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• Each respirocyte stores up to 1.51
billion oxygen molecules, 100% of
which are accessible to the tissues
• To fully duplicate human blood active
capacity, we have to deploy 5.36
trillion devices
• 1 liter of 50% respirocyte suspension,
which puts 954 trillion devices into
your bloodstream. You could then
hold your breath for 3.8 hours, at the
normal resting metabolic rate
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• Respirocytes can provide a temporary replacement for
natural blood cells in the case of an emergency
• If an individual has lost access to a natural oxygen supply due
to drowning, choking or any other
• A resting human uses 240cc/minute (approx) of oxygen
• So a liter of oxygen compressed to 1,000 atmospheres should
be sufficient to maintain metabolism for about 36 hours
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11. • At least four haemoglobin formulations and one fluorocarbon are in
Phase I safety trials, and one company has filed an application to
conduct an efficacy trial
• Most of the red cell substitutes under trial at present have far too
short a survival time in the circulation to be useful in the treatment of
chronic anaemia
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12. • The ability to build products by molecular manufacturing
would create a radical improvement in the manufacture of
technologically advanced products
• Respirocytes could also be used as a complete or partial
symptomatic treatment for virtually all forms of anemia
• Respirocytes can deliver oxygen to muscle tissue faster than
the lungs
• Respirocytes can also be used for other problems with gasses
in the bloodstream
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13. • Article on Nanotechnology and Medicine by Ralph C. Merkle
• A somewhat abbreviated version of this paper was ultimately
published in 1998 as: Robert A. Freitas Jr., "Exploratory
Design in Medical Nanotechnology: A Mechanical Artificial
Red Cell,“ Artificial Cells, Blood Substitutes, and Immobil.
Biotech. 26(1998):411-430. Portions of the 1996 paper differ
slightly from the 1998 published version
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