The Right Materials
One of the most important factors
in biomedical engineering is
biocompatibility – the interaction of different materials with biological tissues. Implanted materials are often chosen because
they are ‘biologically inert’ and as a
result they don’t provoke an
immune response. These can include
titanium, silicone and plastics like PTFE. Artificial heart valves are often coated in a layer of mesh-like fabric made from the same plastic
used for soft drink bottles –
Dacron. In a biological context,
the plastic mesh serves as an inert scaffold,
allowing the tissue to grow over the valve, securing it in place. Some scaffolds used in implants are even biodegradable, providing
temporary support to the growing tissue,
before harmlessly dissolving into
the body.