Blood Substitute - Composition, Advantages, and Disadvantages

What Is Blood?

Blood is an essential connective tissue fluid present in the blood vessels. Blood is composed of different cells circulating in a protein fluid called plasma. Plasma is a fluid mixture of water, protein, and insoluble substances. The main components of blood are, red blood cells (RBC) or erythrocytes, white blood cells (WBC) or leukocytes, and platelets or thrombocytes.

The blood has many vital functions to be carried out; it transports oxygen and nutritional elements to all the tissues and organs of the body, it has antibodies to fight against infection and inflammation, and it regulates the body's temperature and blood clotting.

What Is a Blood Substitute?

Blood substitutes are manufactured artificial blood products. It comprises all the blood components and can be administered in the human body by the blood transfusion process.

Blood substitute products were first introduced in the early 1600s, and the development and research are still continuing for the ideal substitute.

The manufacture of artificial blood can be done in different ways involving synthetic production, chemical isolation, or recombinant biochemical technology. When the blood substitute is manufactured, it can be sterilized to destroy bacteria and viruses while blood transfusion.

The use of artificial blood is done to circulate oxygen to the organ of the body.

What Does an Ideal Blood Substitute Have?

The blood substitute is fabricated blood though it should have properties the same as natural blood or even better.

The following criteria should be followed for the production of blood substitutes -

1. The blood substitute should be safe and reliable for human use.

2. The artificial blood should not produce a reaction in the body.

3. It should be able to carry oxygen to all the tissues and organs of the body.

4. The blood substitute's content should be able to fight against disease-causing bacteria and viruses.

5. The blood substitute should have a long shelf life, so it will be easy to store the unnatural blood.

6. It should be designed in such a way that it can be donated to everyone without affecting the typing phenomenon.

What Are the Types of Blood Substitutes?

There are mainly two types of blood substitutes.

1. Perfluorocarbon (PFC) Blood Substitutes -

• Perfluorocarbon is a synthetic blood substitute; it is composed of fluorine and carbon-containing chemicals.

• They are more effective than plasma in containing and absorbing oxygen and transporting it throughout the tissues and organs of the body.

• The life span of perfluorocarbons is 42 hours.

• Perfluorocarbons are white in color and do not dissolve in natural blood.

• Some examples of perfluorocarbons are - Fluosol DA 20, Oxygent, Perftorom, Oxycyte, and PHER-O2.

2. Hemoglobin-Based Blood Substitutes -

• Hemoglobin-based blood substitutes are produced by using human blood, cow blood, and Escherichia coli bacteria which have the ability to produce hemoglobin.

• Hemoglobin-based blood substitutes are red in color because of the elements used in the production of the substitutes.

• They are smaller than mature red blood cells.

• The life span is one day; the actual red blood cells have a life span of 100 to 120 days.

• Some examples of hemoglobin-based blood substitutes are - Hemopure, PolyHeme, MP40X (Hemospan), Hemotech, and Engineered Hemoglobin.

What Are the Advantages of Blood Substitutes?

The advantages of blood substitutes are -

1. Blood substitutes are suitable for all blood group types because it is made with the blood group typing phenomenon of O negative, which is a universal donor group.

2. Blood substitute helps in emergency cases like roadside accidents or surgical procedures.

3. Artificial blood has a longer shelf life compared to natural blood; therefore, it is easy to store.

4. Donating artificial blood does not affect a person's religious values.

5. The blood substitutes have antibacterial and antiviral properties to fight against the infection during the blood transfusion.

What Are the Disadvantages of Blood Substitutes?

The disadvantages of blood substitutes are -

1. Blood substitute is an advanced medical treatment modality though it may have some errors that can bring a person's life in danger.

2. Blood substitutes can react to the immunological agents present in the body.

3. The function of blood substitutes is limited because they can only transport oxygen to the body parts.

4. The easy availability of artificial blood is limited.

5. They can elevate blood pressure, abdominal discomfort, and allergic reactions.

What Are the Raw Materials Used for the Blood Substitutes?

The raw material used for the production of blood substitutes depends upon the type of blood substitute. In hemoglobin-based artificial blood products, the main component in naturally occurring amino acids can be plant or animal-based. Twenty amino acids with a carboxyl group and a side chain are required for the production. For the other hemoglobin-based products, hemoglobin is isolated from human blood. In synthetically produced hemoglobin blood substitutes, the raw components are warm water, urea, molasses, glucose, acetic acid, alcohol, and liquid ammonia.

What Is the Process of the Production of Artificial Hemoglobin for Blood Substitutes?

The production of blood substitutes is done through different methods. It involves isolation, synthesis of hemoglobin, and modification of molecules.

The production of hemoglobin for blood substitutes is done in the following steps -

1. For the initial protein production, a stain of Escherichia coli that can produce hemoglobin bacteria is fermented with all the suitable growth factors, culture media, and environment.

2. The incubation period of bacteria leads to the multiplication of bacteria, which is then transferred into the seed tank.

3. The seed tank provides a perfect environment for the growth of the bacteria, and all the nutrition and growth factors required for the multiplication of bacteria and proteins are added to it.

4. Then they are shifted to the fermentation stage in the fermentation tank filled with all the essential nutrients, pH control is checked for optimum growth, and ammonia water is added. This leads to the production of hemoglobin.

5. By centrifugation, the hemoglobin is separated and isolated, and shifted to the final processing tank.

6. In the final process, the hemoglobin is mixed with water and electrolytes for the production of artificial blood, and then it is pasteurized for long-term use and packed.

Conclusion -

Blood substitutes are artificial intelligence in medical science, and they can replace natural blood from the body to perform vital functions. Blood substitutes are of two types perfluorocarbon and the other is hemoglobin-based blood substitutes. To date, no ideal blood substitute has been found, but research is still going on. In the future, there will be some suitable blood substitutes for all.