Human Plasma is the yellowish liquid present in the human blood that constitutes 55% of its volume and is responsible for all the major circulation of it throughout the human body. There are many other proteins and substances present in the human plasma in minute quantities that also can be separated through the process of Blood plasma fractionation.

1. Blood plasma fractionation process
Plasma contains a large variety of proteins including albumin, immunoglobulin, and clotting
proteins such as fibrinogen in it. These proteins present in it have many important therapeutic
uses and clinical uses and can work wonders when used in development of various medicines.
These substances are also widely used in medical researches to develop therapies and vaccines
for chronic diseases like cancer, tumors and AIDS etc.
In order to get the benefit of these live saving substances plasma is extracted from the human
blood through a process called blood fractionation. Human Plasma is the yellowish liquid
present in the human blood that constitutes 55% of its volume and is responsible for all the major
circulation of it throughout the human body. When this extraction is carried out we get a
clear solution of plasma in the upper phase, the Buffy coat, which is a thin layer of leukocytes
mixed with platelets in the middle and Erythrocytes (Red Blood Cells) at the bottom of the
centrifuge tube. After getting these components separately in the tube, plasma can be separated
easily and stored for further use.
Now once the Human Plasma is obtained, its various components can be separated for further
usage. However it is also very beneficial and can be used in various forms to create medications
wholly. The process of separating the various components of Human Blood Plasma is called as
Blood plasma fractionation.
The Human Blood Plasma contains thousands of proteins, however, identifying them presents
challenge due to the wide range of concentrations present in it. Let us see different components
and their concentration in it.
Albumin constitutes about 60% of the total protein in plasma and is present at
concentrations between 35 and 55 mg/mL. It is the main contributor to osmotic
pressure of the blood and it functions as a carrier molecule for molecules with low
water solubility such as lipid soluble hormones, enzymes, fatty acids, metal ions, and
pharmaceutical compounds. Due to the structural integrity of albumin it remains stable
under conditions where most other proteins denature.

2. Fibrinogen is present at concentrations 1.5-4.0 g/L in Human Blood Plasma or about 7
µM. It is the principal protein responsible for clotting in the human body.
Immunoglobulins are the substances that fight against infections in human body. Our
bodies create antibodies (Immunoglobulin’s) against disease causing agents when
infections occur.
Apart from these there are many other proteins and substances present in the human plasma in
minute quantities that also can be separated through the process of Blood plasma fractionation.
The first practical large scale method of blood plasma fractionation was developed by Edwin J.
Cohn during World War II. This process is also known as cold ethanol fractionation as it
involves gradually increasing the concentration of ethanol in the solution at 5oC and 3oC. The
Cohn Process exploits differences in properties of the various proteins, specifically, the
high solubility and low pl of albumin. However, at each stage certain proteins are precipitated
out of the solution and removed. The final precipitate is purified albumin.
Several variations to this process also exist, including an adapted method by Nitschmann and
Kistler that uses fewer steps, and replaces centrifugation and bulk freezing with filtration and
diafiltration. However, the ultimate goal of processing is to get a purified component that can be
used for making injection or transfusions. In addition to the clinical uses of a variety of its
proteins, it has many analytical uses too. Blood plasma fractionation obtains it in purified state
that can be utilized for many purposes and have many beneficial factors in it.