What is plasma? Definition, types and importance in health and medicine

Did you know that blood plasma makes up about 55% of the total volume of your blood? It’s essential to nearly every function in your body. Plasma is the liquid component of blood that plays a critical role in transporting nutrients, hormones and proteins throughout your body. It also supports immune defense, blood clotting and waste removal. Let’s explore what plasma is, what it does and why it’s essential in diagnostics, transfusions and medical treatments.

What is plasma?

Plasma is the clear, pale yellow liquid portion of blood that suspends blood cells and makes up around 55% of total blood volume. Composed of about 90% water and 10% dissolved substances - including electrolytes, glucose, clotting factors, hormones and proteins - plasma serves as the medium that carries these components throughout the body.

The body continuously circulates plasma (and other blood components) through blood vessels, ensuring a stable internal environment for cells to function normally and supporting overall health by regulating body temperature, maintaining blood pressure and volume, as well as delivering nutrients and removing waste.

The Importance of plasma in health and medicine

What does plasma do?

• Maintains blood volume and pressure: Plasma helps preserve blood volume and supports stability of the heart and blood vessels. It ensures that blood reaches all tissues efficiently, carrying oxygen, nutrients and hormones to where they’re needed.
• Transports essential components: Plasma transports red blood cells, white blood cells, platelets, nutrients (like glucose and amino acids), hormones, enzymes and waste products (such as carbon dioxide and urea). This transport system helps regulate vital processes such as metabolism and organ function.
• Facilitates clotting and wound healing: Plasma contains clotting factors like fibrinogen and prothrombin and other clotting factors, which are crucial for preventing excessive bleeding and initiating the healing process after injury. Without these elements, even minor cuts could lead to serious blood loss.
• Supports immune function: Plasma is rich in antibodies (immunoglobulins), which help the immune system fight off infections and neutralize harmful bacteria and viruses. This makes plasma and proteins derived from it especially valuable in treating patients with immune deficiencies.
• Removes metabolic waste: Plasma acts as a detoxifying agent, carrying waste products to the liver, lungs, and kidneys for elimination.

Types, classifications and derivatives of plasma products

Plasma can be classified in several ways depending on its composition, method of preparation and clinical application. 

Fresh Frozen Plasma (FFP)

• FFP is collected from whole blood donations and frozen within a few hours to preserve clotting factors and protein content.
• Primary uses: FFP is commonly used in the treatment of patients with coagulation (clotting) disorders, liver disease or those undergoing massive blood transfusions, where restoring clotting capacity is critical.

Convalescent plasma

• Donated by people who have recovered from infections (such as COVID-19, Ebola or severe acute respiratory syndrome -SARS).
• Primary uses: When given to an infected person, convalescent plasma contains antibodies that may help that person fight the specific virus or infectious agent that infected the donor. This is especially important in cases where no vaccines or effective treatments are available.

Platelet-Poor Plasma (PPP)  

• This type of plasma is processed to remove most of the platelets, resulting in plasma with a very low platelet count.
• Primary uses: PPP is often used in laboratory diagnostics, coagulation studies and biomedical research where potential interference by platelets must be minimized.

Cryoprecipitate

• A plasma component rich in fibrinogen, Factor VIII, von Willebrand factor and other clotting proteins.
• Primary uses: Cryoprecipitate is used in the treatment of some bleeding disorders such as hemophilia or von Willebrand disease and in the management of bleeding complications during surgery and in trauma cases.

Plasma-derived medicinal products (PDMPs)

• These include immunoglobulins, albumin, clotting factors, alpha-1 antitrypsin and fibrin sealants, used in immunodeficiency, autoimmune conditions, alpha-1 antitrypsin deficiency and surgeries.

Plasma versus Serum

While both are components derived from blood, their composition differs:

• Plasma contains clotting factors like fibrinogen and is collected using anticoagulants to prevent clotting.
• Serum is what remains after blood has clotted, so it lacks clotting factors but still contains antibodies and other proteins.

Understanding the distinction is crucial in both clinical testing and therapeutic contexts.

Plasma-derived Proteins

Plasma is rich in proteins with specialized roles:

• Albumin: Helps maintain oncotic pressure and transports hormones, drugs, and other substances.
• Immunoglobulins: Involved in immune responses.
• Fibrinogen and other clotting factors (e.g. factor VIII, factor IX, etc.): key proteins in the blood clotting process.
• Alpha-1 antitrypsin: for the treatment of a genetic deficiency that can lead to lung and liver diseases.

These proteins are often isolated and used to produce plasma-derived products for various health conditions. Each plasma type serves a specific purpose in medicine, highlighting its versatility and vital role in diagnostics, treatment and scientific research.

The plasma life cycle: From collection to use

Plasma Collection

Plasma is typically collected using a method called plasmapheresis, a process that involves:

• Drawing a donor’s blood and passing it through a machine that separates the plasma from other blood components.
• Red blood cells, white blood cells and platelets are returned to the donor, while the plasma is collected and stored for medical use.
• This process is safe, takes about 45-60 minutes and allows for more frequent donations than whole blood.

Plasma can also be collected from whole blood donation by separating red cells, white blood cells and platelets in a lab.

Plasma Processing and Storage

After collection, plasma undergoes rigorous testing and treatment to ensure safety and effectiveness. Depending on the intended use, plasma may be:

• Frozen as Fresh Frozen Plasma (FFP) to preserve clotting factors.
• Processed into plasma-derived products, such as immunoglobulins, clotting factor concentrates, albumin solutions, alpha-1 antitrypsin and others.
• Stored under strict GMP (Good Manufacturing Practices) to ensure product integrity and patient safety as well as meet regulations from agencies that assure the safety and effectiveness of medications like the FDA (Food and Drug Administration) in the U.S. and the EMA (European Medicines Agency) in Europe. Frozen plasma is stored at –18°C or colder, and plasma derivatives are preserved using stabilizing techniques for long expiry date.

Clinical and industrial applications of plasma

Plasma is a key component not only in clinical treatments but also in the biopharmaceutical industry, where its proteins and therapeutic potential are used to support and save lives in multiple ways:

Use of plasma in transfusions

Plasma transfusions are routinely used in emergency and surgical settings to treat trauma patients, burn victims and those experiencing shock from blood loss:

• Fresh Frozen Plasma (FFP) is critical for patients experiencing severe bleeding, liver failure or coagulation (clotting) disorders.
• It is often administered during trauma cases, complex surgeries or to counteract the effects of anticoagulant (anti-clotting) medications.
• Plasma exchange therapy
  Used in treatments such as plasmapheresis, where harmful antibodies or toxins are removed from the blood to treat autoimmune diseases like Guillain-Barré syndrome or myasthenia gravis.

Plasma-derived therapies

Plasma serves as the base material for several life-saving therapies:

• Used to produce immunoglobulins, albumin, clotting factor concentrates and alpha-1 antitrypsin.
• These therapies are essential for treating conditions like immune deficiencies, autoimmune diseases, alpha-1 antitrypsin deficiency and hemophilia and other bleeding disorders.
• Plasma protein therapies are targeted treatments developed through advanced separation and purification techniques.

Biopharmaceutical and diagnostic uses

In the industrial sector, plasma proteins play a major role in innovation:

• Used in the development of vaccines, enzyme replacement therapies and diagnostic reagents.
• Convalescent plasma, rich in disease-specific antibodies, is currently being explored and has been studied and used as a therapeutic option during outbreaks of viral infections, including COVID-19, Ebola and Zika.
• Albumin is essential in stabilizing certain medications and ensuring these medications are effectively delivered to where they are needed in the body.
• Plasma is being studied for its role in healing and tissue regeneration, including the use of platelet-rich plasma (PRP) therapies in orthopedics and dermatology.

Emerging applications and future potential innovations

Ongoing research continues to uncover new uses for plasma in modern medicine:

• Biomarker analysis: Plasma is being used to detect signals (biomarkers) in the blood indicating the presence of cancer, cardiovascular conditions and metabolic disorders.
• Blood plasma testing: Analysing levels biomarkers in plasma helps to assess hydration, blood glucose, hormone levels and electrolyte balance.  
• Drug testing and development: Plasma is analysed to evaluate levels of medication in the body and how long the medications remain active in the body.

Plasma also supports gene therapy delivery systems and the creation of advanced wound-healing treatments. As demand grows for biologics and precision therapies, plasma is positioned as a strategic resource in healthcare innovation, both now and in the future.

From emergency rooms to research labs, plasma continues to be an indispensable resource. Its versatility supports both individual patient care and large-scale therapeutic production, bridging the gap between clinical need and industrial innovation. Plasma supports the immune system, enables clotting in the body and serves as a source for developing life-saving drugs. Understanding plasma’s functions and applications helps both patients and providers to make informed decisions about care and treatment.

As demand for plasma-derived therapies continues to rise, promoting awareness and encouraging donation are more important than ever.

Want to learn more about related topics? Explore our medical glossary here.