Smart Sutures

A new twist on implantable sensors could provide more detailed information on the biological processes in the body than skin-mounted sensors would ever be capable of detecting. The approach involves using specially treated sutures to measure a variety of chemical and mechanical properties so that doctors can continuously monitor a patient’s physical and biochemical status unobtrusively.

For example, sensors for measuring electrical signals in a muscle could be created by coating a fiber with conductive ink. Physical strain – a useful parameter for monitoring wound healing – could be assessed by embedding a stretchy thread with silicone and carbon nanotubes to make a piezoelectric fiber. And threads could be coated with a variety of compounds to make them sensitive to acidity, electrolyte concentrations or other chemical dynamics. They can even be made to exploit a property of thread known as “wicking,” which allows liquid to travel along the fibers via capillary action, to siphon small amounts of interstitial fluid that surrounds tissues and cells.

Human clinical trials have not yet commenced; however, one area of interest is to use the sutures for monitoring wound healing in diabetics, where the ability to diagnose and treat problems early could reduce the possibility of losing a limb.