Skip to main content
  • Expression of Interest

    Fiber Optic Brain Interface (FOBI)
    biophysics, fiber optics, fluorophore, lasers, fluorescence, life time,

        Neurons talk to each other through relatively small electrical impulses. The time period of a pulse (action potential) is as big as 1ms and the voltage change is about 120 mV. A major drawback (or maybe an advantage) is that neurons don’t create an action potential as a result of light irradiation. Communication between Brain and Computer can be made, in a direct way, only through electric fields. Using wires to collect the information is not the best way but is the easiest. Using electrical wires to take voltage measurements on the surface of the brain or inside of the brain is raising a lot of problems like: metallic ions release, electromagnetic interference and biological degradation.


    The project evolves around two types of biosensors based on fiber optics (FO), capable of:

    1. measure the low voltage in a very small volume (the tip of the FO) without disturbing the local field of the cells. (name: FORX)

    2. create a low voltage, 200mV on the tip surface of the FO based on the pump laser light that is in the FO core. (name: FOTX)


       The tip surface of the FORX is functionalised by a fluorophore trapped in a nanoscale ripple structure made of gold. The fluorescence lifetime of the fluorophore will be measured as a function of local voltage (from -200 mV to +200 mV). The fluorescence of the biosensor will be recorded based on the fluorescence signal obtained in the FO. The fluorescence of different fluorophore will be examined in order to get a high response at the variation of the electric field. The assessed parameters for fluorophore will be fluorescence intensity, fluorescence wavelength shift and fluorescence lifetime. The response of the biosensor should be better than 100 microseconds.

       The tip surface of the FOTX is functionalized with a small piezoelectric crystal deposit on the surface of the tip. The laser pulses from the core will create a small shock wave on the surface of the piezo electric crystal. Gold electrodes can be applied on the surface of the crystal to enhance the process of creating an action potential. The bio-device should be able to create pulses in the rage of 0.1-10 ms with an amplitude greater than 200 mV.

    The active surface of the bio-device is similar with the section of the FO and the volume should not be more than 0.1 mm3. The functionality of the FO bio-devices will be assessed by an intracranial rat implant that will collect data regarding the local brain activity and in the same time brain stimulus will be applied via FOTX.


    Fiber optics, Laser, DSP microcontroller , Telecom, Brain Implants and Neurology.


    We need partners with good background in biosensors and implants to put this project (FOBI) in practice... Our expertise is in lasers, Nonliniar Optics, Cis-Trans azo dyes transition, Liquid Cristals and Biophysics. The  background of my mentors and I can be consulted here:

    Cristian Sarpe                     

    Palarie Ion                          

    Marius Ciprian Varut