Placing sensors inside the human body can help researchers and physicians to understand and treat a variety of medical conditions. However, while implanting a sensing device may be routine, having it remain in the body long enough to perform its job and then be safely removed is an entirely different and significant challenge.
Now a team of Italian and Greek researchers have embedded fiber Bragg gratings, a type of device that reflects certain light wavelengths and can be used as a sensor, inside of dissolvable optical fibers. This new technology may allow the long-term monitoring of the biomechanical and chemical properties of various organs and anatomical features inside the body.
Fiber Bragg gratings placed into optical fibers are routinely used to measure stresses placed on bridges, commercial airliner wings and other areas where detailed, real-time monitoring is critical. The newly-developed fiber Bragg gratings are able to break down, similar to absorbable sutures and, because they have been embedded into optical fibers that are also bioresorbable, they should be safe for use inside the body. Ideally, they would be implanted, left inside the body to perform sensing and eventually disappear completely without the need for removal.
The researchers envision that this technology would be especially useful for tumor targeting, as the same optical fiber that can deliver laser radiation can also be used to sense the temperature of the tumor and surrounding tissues. This capability could improve the safety of tumor treatments while achieving greater accuracy at removing unwanted tissue.
Below is some detail from the actual study abstract posted in Optics Letters:
Bragg gratings, with average refractive index changes of 5.8×10−45.8×10−4, were inscribed using 193 nm excimer laser radiation. Results on the dissolution of the irradiated fiber in simulated physiological conditions are presented after immersing a tilted Bragg grating in a phosphate buffered saline solution for 56 h; selective chemical etching effects are also reported. The investigations performed pave the way toward the use of such phosphate glass fiber Bragg gratings for the development of soluble photonic sensing probes for the efficient in vivo monitoring of vital mechanical or chemical parameters.
To learn more about this study, please go HERE.