Scientists from the Institute of Electronic Structure and Laser (IESL), of the Foundation for Research and Technology-Hellas (FORTH), Greece, and, the Politecnico di Torino, Italy demonstrated for the first time temperature sensors based on optical fibers designed to completely dissolve in biological fluids or water. Such types of bio-resorbable optical fiber sensors, which exhibit low toxicity and high solubility, can be particularly attractive for numerous biomedical applications, including the efficient monitoring of bone fractures healing process, or for the safer exploration of the operation of the human brain, or other internal organs. The development and operation principle of those bioresorbable optical fiber sensors was recently published in the international journal Optics Letters of the Optical Society of America, while this demonstration was further highlighted by the same society as a breakthrough technology.

These specialty optical fibers, which have a diameter twice as that of a human hair, are gradually dissolved into solutions with temperature and pH resembling those of the human body, within typical times that span between several hours and few days, while being capable of delivering temperature sensing measurements until the final stages before their final dissolution; also, they are safe for the human body. As further reported, the wet dissolution process of those optical fiber sensors is fully controlled by the laser irradiation conditions, opening new prospects for the realization of novel opto-fluidic sensors and actuators that will be shaped and operate, after their implantation into the human body.

The research team of IESL-FORTH which consists of the Application Research Scientist Maria Konstantaki, the Post-doctoral Scientist Ioannis Konidakis and the Director of Research Stavros Pissadakis, leader of this investigation and of the Photonic Materials and Devices Laboratory, employed advanced photosensitivity processes based on deep ultraviolet laser radiation for processing those optical fibers, while also studying their dissolution and sensing properties. These phosphate-glass optical fibers were developed and drawn by the Politecnico di Torino group, including among others post-doctoral scientist Diego Pugliese and Professor Daniel Milanese, who directed the fabrication process.

The research teams of IESL-FORTH and Politecnico di Torino continue their investigations on the specific type of bioresorbable optical fiber sensor targeting both their further photonic and biochemical optimization, aiming at  improving their performance and bioresorbing behavior.

For more information, please contact Dr Stavros Pissadakis, Director of Research, IESL-FORTH, http://www.iesl.forth.gr/users/pmdl/

Email: pissas@iesl.forth.gr

Publication link: https://www.osapublishing.org/ol/abstract.cfm?uri=ol-43-4-671