Artificial Red Blood Cells Using Nanotechnology

 

Lakshmi Narasimha*, A. Tamil Selvan, D. Jairam, R. Suthakaran

Department of Pharmaceutics, Teegala Ram Reddy College of Pharmacy,

Meerpet, Saroor Nagar (M), Hyderabad -97

*Corresponding Author E-mail: sutrakar.skumar35@gmail.com

 

ABSTRACT:

Nanotechnology marks a drastically different approach in manufacturing. Instead of sealing materials down to create something, nanotechnology produces things by building then up piece by piece on a molecular level by providing broad scope. Now, In medical field we deal in detail about nanotechnologies potential in developing artificial red blood cells design of artificial RBC and their efficiency compared to normal RBC working of the developed artificial RBC their use in the medical field. The application is to provide metabolic support in the event of impaired circulation. Controlled release of oxygen from the diamonded sphere could be done using the selective transport method proposed by .It shows transport in the wrong direction but simply, the ability to heal disease that are caused due to the deficiency of oxygen and make the body stronger: all these and more are possible given the potential of nanotechnology. Machines could be produced, down to the size of viruses, which would work at incredible speeds. Through the use of nanotechnology, the number of possible worlds we can create is limited only by what we can imagine.

 

KEYWORDS: Artificial RBC, Nano technology, Controlled release of oxygen, diamonded pressure tank, nanobots.

 

 


1.     INTRODUCTION TO NANOTECHNOLOGY:

1.1. What is Nanotechnology?

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. Because of this, nanotechnology is also referred to as molecular manufacturing. Nanotechnology is a result of the intersection of diverse fields such as physics, biology, engineering, chemistry, and computer science to name a few.

 

Nanotechnology marks a drastically different approach in manufacturing. Instead of scaling materials down to create something, nanotechnology produces things by building them up piece by piece on a molecular level by providing broad scope.

 

Nanotechnology has the potential for a nearly limitless number of applications in a wide range of fields. One such field is computer science, in which nanotechnology presents a new challenge.

 

Computer chips are shrinking by a factor of four every three years (Moore’s law). Another field in which nanotechnology has a wide reach of potential effects is medicine. Molecular manipulation would aid in killing off cancer cells. Telecommunications is another field in which nanotechnology will yield advances. Nanotechnology will allow a telephone or computer to connect to the global data network using inexpensive string or tape.

 

1.2. History of Nanotechnology:

The origins of nanotechnology are rooted in a lecture given in 1959 by Richard P. Feyman entitled “There’s Plenty of Room at the Bottom.” Although the ideas presented in this lecture were wholly theoretically at the time, Feyman stated that the laws of physics do not prevent us from manipulating individual atoms or molecules12.

 

2. Nanotechnology in Medical field:

Nanotechnology became a driving force in today’s medical field. Many new applications are evolving day by day using the help of nanotechnology. Medical field is using nanotechnology’s success to plethora. Nanobots are created using the technology and these devices have the capability of scanning entire body and look at the flaws present in the body and to recover them to the maximum limit.

 

2.1 Nanobots used in medicine:

Nanobots used in medical field help in traversing through blood vessels in the Circulatory system. They are capable of detecting the tumors and also can cure them to certain extent. They are designed to such accuracy that they can go to the correct position using the GPS and can perform the necessary operation that is intended to perform11.

 

The below depicted prototype is collected from an article featured in the Computer Graphics and Geometry Journal. Here, we see nanorobot delivering a molecule to the organ inlet -- represented by the white cylinder.

 

Fig : 1 The prototype shows the nanorobot that is traversing through the blood vessels. Now we look at the size of the nanorobots that are depicted in the diagram in concise.

 

2.2 Size of Nanobots used:

Drexler proposed for molecular mechanical logic that including system overheads (power, connections, etc) the volume per element should still be less than 100 cubic nanometers. A 10,000 element logic system (enough to hold a small processor) would occupy a cube no more than 100 nanometers on a side. That is, a volume only slightly larger than 0.001 cubic microns would be sufficient to hold a small computer. This compares favorably with the volume of a typical cell (thousands of cubic microns) and is even substantially smaller than sub cellular organelles. Operating continuously at a gigahertz such a computer would use less than 10^-9 watts6. By comparison, the human body uses about 100 watts at rest and more during exercise. Slower operation and the use of would reduce power consumption, quite possibly dramatically.

 

A variety of molecular sensors and actuators would also fit in such a volume. A molecular "robotic arm" less than 100 nanometers long should be quite feasible, as well as molecular binding sites 10 nanometers in size or less. A single red blood cell is about 8 microns in diameter (over 80 times larger in linear dimensions than our 100 nanometer processor). Devices of the size range suggested above (~0.1 microns) would easily fit in the circulatory system and would even be able to enter individual cells.

 

3. Materials and working methods and application:

Materials:

The oxygen molecules would be released out side at a constant rate depending on the need present at that time. This is calculated by the sensors that are present at the outer side of the artificial red blood cell. More sophisticated systems would release oxygen only when the measured external partial pressure of oxygen fell below a threshold level, and so could be used as an emergency reserve that would come into play only when normal circulation was interrupted.

 

Working Methods:

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 By comparison, a liter of blood normally contains 0.2 liters of oxygen (approx), while one liter of our spheres contained 530 liters of oxygen 8 (where "liter of oxygen" means, human oxygen consumption, one liter of the gas under standard conditions of temperature and pressure). Thus, our spheres are over 2,000 times more efficient per unit volume than blood; taking into account that blood is only about half occupied by red blood cells, our spheres (artificial RBC) are over 1,000 times more efficient than red blood cells.

 

Application:

The application is to provide metabolic support in the event of impaired circulation. Poor blood flow, caused by a variety of conditions, can result in serious tissue damage. A major cause of tissue damage is inadequate oxygen. A simple method of improving the levels of available oxygen despite reduced blood flow would be to provide an "artificial red blood cell." This may help to perform the metabolic activities for some time even during irregularities.

 

Artificial RBC are also known as:

1)     Respirosites

2)     Gas carriers

3)     Nanobots or nano robots

4)     diamondoid pressure tank

 

4.     Nanotechnology for developing Artificial Red Blood Cells:

Nanotechnology has the potential of unlimited number of applications in medical field and we now deal in detail about nanotechnologies potential in “developing Artificial Red- Blood Cells” 2design of Artificial Red Blood Cells and their efficiency compared to the normal Red Blood Cells working of the developed Artificial Red Blood Cells their use in the medical field.

 

4.1 Introduction to application:

The application is to provide metabolic support in the event of impaired circulation. Poor blood flow, caused by a variety of conditions, can result in serious tissue damage. A major cause of tissue damage is inadequate oxygen. A simple method of improving the levels of available oxygen despite reduced blood flow would be to provide an "artificial red blood cell." This may help to perform the metabolic activities for some time even during irregularities.

 

4.2Design of the Artificial Red Blood Cell:

 

Fig : 2 artificial red blood cell (nano bot)

 

Artificial Red Blood Cell:

A sphere with an internal diameter of 0.1 microns (100 nanometers) filled with high pressure oxygen at 1,000 atmospheres (about 10^8 Pascal’s approx). The oxygen would be allowed to trickle out from the sphere at a constant rate (without feedback).

 

Diamond has a Young’s modulus of about 10^12 Pascal’s. An atomically precise diamonded structure should be able to tolerate a stress of greater than 5 x 10^10 Pascal’s (5% of the modulus). Thus, a 0.1 micron sphere of oxygen at a pressure of 10^8 Pascal’s could be contained by a hollow diamonded sphere with an internal diameter of 0.1 microns and a thickness of less than one nanometer.16 This thickness, thin as it is, results in an applied stress on the diamond of well under 1% of its modulus -- from a purely structural point of view we should be able to use a very large "bulky ball," i.e., a sphere whose surface is a single layer of graphite.

 

4.2Escaping Body’s Immunity System:

The other most complex issue involved in the selection of the material is the reaction of the body's immune system. While some suitable surface structure should exist that does not trigger a response by the immune system. To give afeeling for the range of possible surface structures, the hydrogenated diamond surface could have a variety of "camouflaged" molecules covalently bound to its surface. A broad range of biological molecules could be anchored to the surface, either directly or via polymer tethers 11.

 

4.3 Comparing size of Normal Red Blood Cell to Artificial RBC:

 

Fig 3 The picture shown above clearly shows the variation of size present between the normal red blood cells and artificial red blood cells. The small balls that are depicted are the artificial red blood cells and the large ones are the normal red blood cells.

 

Due to this scaling down of the devices they are able to traverse through the blood vessels and the circulatory system. The Artificial Red blood cells are highly efficient when compared to the normal red blood cells in maintaining metabolism. The efficiency of these miniature devices is dealt in detail in the section following.

 

4.4 Calculation Showing the Efficiency of Artificial Red

Blood Cells:

1)  By  Vander Waal’s equation of state:

(p+a/V^2)(V-b)=RT

 

Where:  

P is the pressure,

V is the volume per mole,

a = 1.36 atm liter^2/mole^2 and b = 0.03186 liter/mole

R = 0.0820568 liter-atmospheres/mole-Kelvin.

R is the universal gas constant,

T is the temperature in Kelvin’s, and

a and b are constants specific to the particular gas involved.

 

For oxygen:

·         A mole of oxygen at 1,000 atmospheres and at body temperature (310 Kelvin’s) occupies 0.048 liters, or about 21moles/liter.

·         A mo le of oxygen at 1 atmosphere and 310 Kelvin’s occupies 25.4

·         liters, or about 0.04moles/liter.

·         Ø This implies a compression of  530 to 1(approx).

 

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 By comparison, a liter of blood normally contains 0.2 liters of oxygen (approx), while one liter of our spheres contained 530 liters of oxygen (where "liter of oxygen" means, human oxygen consumption, one liter of the gas under standard conditions of temperature and pressure) 10. Thus, our spheres are over 2,000 times more efficient per unit volume than blood; taking into account that blood is only about half occupied by red blood cells, our spheres (artificial RBC) are over 1,000 times more efficient than red blood cells.

 

4.5 Working of the Artificial Red Blood Cells:

Controlled release of oxygen from the diamonded sphere could be done using the selective transport method proposed by Drexler and is illustrated in figure shows transport in the "wrong" direction (for this application), but simply reversing the direction of rotor motion (anti clock wise direction) would result in transport from inside the reservoir to the external fluid. By driving a rotor at the right speed, oxygen could be released from the internal reservoir into the external environment at the desired rate.

 

Fig : 4 rotor designe in Arificial Red Blood Cell .

 

The oxygen molecules would be released outside at a constant rate depending on the need present at that time. This is calculated by the sensors that are present at the outer side of the artificial red blood cell. More sophisticated systems would release oxygen only when the measured external partial pressure of oxygen fell below a threshold level, and so could be used as an emergency reserve that would come into play only when normal circulation was interrupted 9.

 

Full replacement of red blood cells would involve the design of devices able to absorb and compress oxygen when the partial pressure was above a high threshold (as in the lungs) while releasing it when the partial pressure was below a lower threshold (as in tissues using oxygen). In this case, selective transport of oxygen into an internal reservoir (by, for example, the method shown in Figure 1) would be required. If a single stage did not provide a sufficiently selective transport system, a multi-staged or cascaded system could be used.

 

Compression of oxygen would presumably require a power system, perhaps taking energy from the combustion of glucose and oxygen (thus permitting free operation in tissue). Release of the compressed oxygen should allow recovery of a significant fraction of the energy used to compress it, so the total power consumed by such a device need not be great.

4.6 Advancement to the application:

If the device were to simultaneously absorb carbon dioxide when it was present at high concentrations (in the tissue) and release it when it was at low concentrations (in the lungs), then it would also provide a method of removing one of the major products of metabolic activity1. Calculations similar to those given above imply a human's oxygen intake and carbon dioxide output could both be handled for a period of about a day by about a liter of small spheres.

 

As oxygen is being absorbed by our artificial red blood cells in the lungs at the same time that carbon dioxide is being released, and oxygen is being released in the tissues when carbon dioxide is being absorbed, the energy needed to compress one gas can be provided by decompressing the other. The power system need only make up for losses caused by inefficiencies in this process. These losses could presumably be made small, thus allowing our artificial red blood cells to operate with little energy consumption7.

 

4.7 Result of Failure in Artificial RBC:

·         There is just one failure that can be observed in concern to the application it is, Failure of a 0.1 micron sphere would result in creation of a bubble of oxygen less than 1 micron in diameter. Occasional failures could be tolerated. Given the extremely low defect rates projected for nanotechnology, such failures should be very infrequent.

·         The failure rate of the Artificial Red Blood Cells is very minimal. This is the best application of Nanotechnology in the medical field.

·         The above described is the latest innovative application of the nanotechnology. As the nanotechnology progresses it helps in achieving high prospects for the medical field.

·         The Nanobots that are used are so powerful that they can scan through every tissue in our body and report the abnormality in our body. With this advancement we can hope for a day where we are resistant to the diseases and are in a stage toward them off.

 

5. Applications of Artificial RBC over Natural RBC (Red Blood Cells)

1.     In holding of gas molecules Artificial RBC has the capacity of 1x109 times more when compare to that of natural RBC

2.     It does not trigger the Body Immune system as that of Effected RBC (like cancer, allergic conditions etc.,)

3.     When compare to that of RBC there is no chance of Hyper or Hypo Oxymia due to the presence of sensors which has the capacity to calculate the amount of oxygen requirement of a gas molecules.

4.     Natural RBC carries only 4 molecules of oxygen where as Artificial RBC has the capacity to carry more than 200 molecules of oxygen at a time in a compressed condition which increases the efficiency of a molecule.

5.     Respirocytes can provide a

6.     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 form of asphyxia, respirocytes can release oxygen throughout the bloodstream until the danger has been removed. Respirocytes can also be

7.     Used for other problems with gasses in the bloodstream. If one inhales carbon monoxide or other  poisonous gasses, special respirocytes designed to capture those particular molecules can be used to clean the body quickly.

8.     Another useful application is in deep sea diving. If a diver surfaces too quickly, he or she of ten suffers from the "bends", a problem caused by dissolved nitrogen bubbles in the blood stream. Respirocytes could be designed to capture nitrogen molecules during dives. Respirocytes could be employed as a long-duration

9.     Perfusant to preserve living tissue, especially at low temperature, for grafts (kidney, marrow, liver and skin) and for organ transplantation.

10.   Respirocytes could also be used as a complete or partial symptomatic treatment for virtually all forms of anemia. Respirocytes would help treat a wide

11.   Variety of lung diseases and conditions ranging in severity from hay fever, asthma and snoring to tetanus, pneumonia and polio. The devices could also contribute to the success of certain extremely aggressive cardiovascular and neurovascular procedures, tumor therapies and diagnostics. Then there is

12.   The "nanolung." An interesting design alternative to augmentation infusions is a therapeutic population of respirocytes that loads and unloads at an artificial nanolung, adiamondoid pressure tank the aerobots in this scene are used in the lungs for detection of pathogens, medical treatment, and cell repair. In scene one, the aerobot's wings are extended. In two, the wings are retracted implanted in the chest, which exchanges gases directly with the natural lungs or with an external gas supply such as an air hose. A less-conservative nanolung design could allow you to survive for up to 5 days without drawing a breath.

13.   Respirocytes can deliver oxygen to muscle tissue faster than the lungs can provide, for the duration of the sporting event. Indeed, our baseline respirocyte can deliver 236 times more oxygen to the tissues per unit volume than natural red cells, and enjoys a similar advantage in carbon dioxide transport.

14.   Artificial blood substitutes may also have wide use in veterinary medicine, especially in cases of vehicular trauma and kidney failure where transfusions are required, and in battle field applications demanding blood replacement or personnel performance enhancement.

5.1 Comparison chart

 

Table : 1 Comparison chart

 

NATURAL RBC

ARTIFICIAL RBC

Physical features:

 

These are bi-concave disc shaped, and have no nucleus.

These are spherical in shape and made up of diamond

Life span:

120 days.

5-8 months.

Types:

There is only one type of RBCs found in the blood.

There are various sizes depending upon the rotors present inside it.

Circulatory

Cardiovascular system

Cardiovascular system (Gas carrier).

Total count RBC 700:1

4.5 million - 5.5 million per cubic mm

10-12 million per cubic mm.

Functions:

 

It supplies 4 oxygen molecules to different parts of the body and carries 4 carbon dioxide molecules and other waste products.

It carries more than 200 molecules of oxygen or carbon dioxide molecules and supplies according to the requirement.

Presence in blood:

Makes up nearly 45% of our blood.

less hano 20% of the blood.

Components:

Hemoglobin

Rotors , sensors , micro chips, detectors,

Production:

Produced in red bone marrow

Artificially made and injected into the blood.

Movement:

They move in blood vessels eventually squeezing through capillaries.

They move in blood vessels normally in a specified path using flow of blood.

Significance of irregularity in count:

A very low RBC count will result in anemia.

No side effects.

Nuclei:

RBC do not have nuclei in humans

Has micro chip to monitor.

Shape:

Round and can change shape

Have different kinds of shapes depending on no of sorting rotors used in it

 


6. Other applications of Nanotechnology:

Nanotechnology has the potential of having unlimited number of applications and here we deal with the application of nanotechnology in various fields.

 

1.     Nanotechnology is used in the computer industry. The basis of today’s computers is silicon microchips – tiny wafers holding millions of transistors which were made possible by nanotechnology.

2.     Nanotechnology has a wide reach of potential effects is medicine with help of Nanobots can cure the cancer disease of any level.

3.     Nanotechnology also finds its usage in the telecommunication field in the easy to connect networks.

4.     Nanotechnology finds its application in imaging the body. Nanoprobes help in diagnosing the body and help in finding the abnormality.

5.     Nanotechnology also helps in reducing the percentage of heart attacks. A heart attack is mainly due to the clotting in main arteries. Nanorobots act as Shepard in removing these clots and help in avoiding heart attacks.

6.     Molecular nanotechnology has the potential to produce space hardware with tremendous improvement in performance and reliability at substantially lower cost.

 

7. FUTURE OF NANOTECHNOLOGY:

Nanotechnology is a field still in its infancy, probably years away from practical applications3. But a fervent, increasingly influential community of researchers is trying not only to make it a technical reality but a force for social transformation as well.

 

With the kind of Nanobots discussed earlier, we should be able to explore and analyze living systems in greater detail than ever before considered possible. The Autonomous molecular machines, operating in the human body, could monitor levels of different compounds and store that information in internal memory helping in good medical support. Thus nanotechnology faces a bright future and its applications would prosper by the advancement in the technology.

 

8. CURENT STATUS:

Robert A. Freitas, Jr. is Senior Research Fellow at the Institute for Molecular Manufacturing (IMM) in Palo Alto, California, and was a Research Scientist at Zyvex Corp. (Richardson, Texas), the first molecular nanotechnology company, during 2000-2004.He received B.S. degrees in Physics and Psychology from Harvey Mudd College in 1974 and a J.D. from University of Santa Clara in 1979.

 

The theoretical analysis of carbon atom (or dimer) placement on diamond has involved many researchers including Cagin,248 Drexler,126 Dzegilenko,249 Freitas, 250–252 Goddard, 248 Mann, 252 Merkle, 250–254 Peng, 251-252 Saini, 249 Srivastava, 249 and Walch. 248-253 The feasibility of precisely inserting individual

 

carbon atoms, small hydrocarbon species, or small clusters of carbon atoms on a C(111) or C(100) diamond surface at specific sites was initially supported first by the computational work of Walch and Merkle.253 Walch and Merkle analyzed several mechanosynthetic reactions, including placement of a carbon dimer onto a C(111) surface, insertion of a positionally controlled carbene into that dimer, and the insertion of a positionally controlled carbene into a surface dimer on a C(100) surface using a 9-atom cluster to model the diamond surface.

 

The artificial mechanical red blood cell or “respirocyte”285 is a bloodborne spherical 1-micron diamondoid 1000-atmosphere pressure vessel (Fig.8) 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 acidity5. The nanorobot is made of 18 billion atoms precisely arranged in a diamondoid pressure tank that can be pumped full of up to 3 billion oxygen (O2) and carbon dioxide (CO2) molecules.Later on, these gases can be released from the tank in a controlled manner using the same molecular pumps.Respiroc ytes mimic the action of the natural hemoglobin-filled red blood cells.Gas concentration sensors on the outside of each device let the nanorobot know when it is time to load O2 and unload CO2 (at the lungs), or vice versa (at the tissues) (Fig.9).An onboard nanocomputer and numerous chemical and pressure sensors enable complex device behaviors remotely reprogrammable by the physician via externally applied acoustic signals.

 

Each respirocyte can store and transport 236 times as much gas per unit volume as a natural red cell. So the injection of a 5 cc therapeutic dose of 50% respirocyte saline suspension, a total of 5 trillion individual nanorobots, into the human bloodstream can exactly replace the gas carrying capacity of the patient’s entire 5.4 liters of blood 2. If up to 1 liter of respirocyte suspension could safely be added to the human bloodstream,7 this could keep a patient’s tissues safely oxygenated for up to 4 hours in the event a heart attack caused the heart to stop beating, even in the absence of respiration.Primary medical applications of respirocytes will include transfusable blood substitution; partial treatment for anemia, perinatal/ neonatal and lung disorders; enhancement of cardiovascular/ neurovascular procedures, tumor therapies and diagnostics; prevention of asphyxia; artificial breathing; and a variety of sports, veterinary, battlefield and other uses.

 

9. CONCLUSION:

Nanotechnology, "the manufacturing technology of the 21st century," enables us to economically build a broad range of complex molecular machines. It will let us build fleets of computer controlled molecular tools much smaller than a human cell and built with the accuracy and precision of drug molecules.

 

As Drexler asserts that molecular manufacturing can produce materials stronger and lighter than anything currently available 1. Better spacecraft, devices to repair living cells, the ability to heal disease and make the body stronger: all these and more are possible given the potential of nanotechnology. Machines could be produced, down to the size of viruses, which would work at incredible speeds. Through the use of nanotechnology, the number of possible worlds we can create is limited only by what we can imagine.

 

Thus nanotechnology is becoming the part and parcel of the modern technology.

 

10. REFERENCES:

1)     Chang TMS. Artificial cells. Monograph. Charles C Thomas, Springfield, IL, 1972

2)     National Nanotechnology Initiative: Research and Development FY (2002);

3)     M.C.Roco, “National Nanotechnology Investment in the FY, 2004; Budget Request,” AAAS Report XXVIII: Research and Development FY (2004);

4)     “Nanomedicine: Grounds for Optimism, and a Call for Papers,” Lancet 362 (2003):673; P_5258_14984

5)     “RB-162 Biomedical Applications of Nanoscale Devices,” Business Communications Company, Inc., 25 Van Zant Street, Norwalk, CT 06855 (2003);

6)     R.A.Freitas, Jr., Nanomedicine, Volume I: Basic Capabilities, Landes Bioscience, Georgetown, TX (1999);

7)     Chang TMS. Monograph on “ARTIFICIAL CELLS: Biotechnology, Nanotechnology, Blood Substitutes, Regenerative Medicine, Bioencapsulation, Cell/Stem Cell Therap. World Science Publisher, 2007 452 pages.

8)     Blood Substitutes: Principles, Methods, Products and Clinical Trials. Vol.1 Basel Karger,1997.

9)     Nanobiotechnological modification of hemoglobin and enzymes from this laboratory. Biochimica et Biophysica Acta: proteins and Proteomics 2008;1784:1435-144

10)   Oxygen Carriers based on Nanobiotechnology in book on “Artificial Cells: Biotechnology, Nanomedicine, Regenerative Medicine, Blood Substitutes, Bioecapsulation and Cell/Stem Cell Therapy. 2007, 31-61

11)   Gould, S. A. et al. The life-sustaining capacity of human polymerized Hb when red cells might be unavailable. J. Am. Coll. Surg. 2002;195, 445–452 .

12)   Pearce, LB, MS Gawryl, VT Rentko, PF Moon-Massat and CW Rausch.HBOC-201 (Hb Glutamer-250 (Bovine), Hemopure): Clinical Studies. In Blood Substitutes

13)   Winslow, R [ed] Academic Press San Diego,2006; pp437-4509.

14)   Chang, TMS .A Nanobiotechnologic Therapeutic that Transport Oxygen and Remove Oxygen Radicals: For Stroke, Hemorrhagic Shock and Related Conditions. In book on “Artificial Cells: Biotechnology, Nanomedicine, Regenerative Medicine, Blood Substitutes, Bioecapsulation and Cell/Stem Cell Therapy. 2007; 62-92

15)   Chang, TMS. Nanotechnology based Artificial Red Blood Cells in book on “Artificial Cells: Biotechnology, Nanomedicine, Regenerative Medicine, Blood Substitutes, Bioecapsulation and Cell/Stem Cell Therapy. 2007;93-128

16)   Yu WP, Chang TMS. Submicron biodegradable polymer membrane Hb nanocapsules as potential blood substitutes. Artificial Cells, Blood Substitutes and Immobilization Biotechnology, An International Journal 1996; 24:169-18

 

 

 

 

Received on 03.09.2014          Modified on 10.09.2014

Accepted on 07.10.2014          © RJPT All right reserved

Research J. Pharm. and Tech. 7(11): Nov. 2014 Page 1323-1329