Perfuorocarbon-based substitutes
Mouse in PFC fluid What exactly are perfluorocarbons?

Perfluorocarbons (PFCs) are synthetic liquids that dissolve large volumes of oxygen, and also have the capacity to transport carbon dioxide. These chemical liquids were first made famous in the 1960s when scientists, led by Professor Leland Clark at the University of Alabama showed that a mouse could survive for up to 10 minutes when totally sub-merged in PFC liquid.

How can an artificial, synthetic fluid act as a blood substitute?

Many scientists believe PFC liquids are the answer to development of an effective blood substitute. This belief is supported by a number of the favourable characteristics associated with PFCs, shown below:

 
Characteristic of PFCs Advantage to substitute development
High respiratory gas solubility PFCs dissolve large volumes of both oxygen and carbon dioxide, which are easily extracted by the body's tissues
Synthesised from non-biological sources Potentially infinite supply, and also, no potential for disease transmission
Highly stable PFCs do not require chemical modification (unlike haemoglobin-based substitutes) as they show no metabolic breakdown in the body. Stability ensures simple storage requirements
Chemically inert PFCs do not undergo biochemical reaction in the body, and can be excreted from the body via the lungs in exhalation
Easily sterilisable Stable structure can withstand high temperatures, allowing for sterilisation against contaminants
Low cost PFCs can be produced at medical grade quality on a large, commercial scale. Low cost makes them an attractive option to low health care budgets of emerging countries

 

Whilst PFC liquids have many attractive features, they do have shortcomings, these include:

 

1. Non-mixing with water -

 Before administration, PFCs must be prepared as emulsions, as PFCs will not mix with blood plasma. These emulsions can sometimes be unstable which means they do not last long in the circulation.
2. Requirement for high oxygen levels - To dissolve adequate quantities of oxygen into PFCs requires patients to breathe 70-100% oxygen through a mask during surgery. This potentially limits their application to hospital settings where such supplementary oxygen can be provided.
3. Flu-like symptoms - Human clinical trials with PFCs have observed flu-like symptoms in some patients.

 

 
RETURN TO TOP