Distributed Optical Fiber Sensors Laboratory

Distributed acoustic sensors repurposes any telecommunication optical fiber in a long chain of microphones; Distributed acoustic sensors can be applied to seismic monitoring, road & railway traffic monitoring, pipeline intrusion & leak detection, etc. Different methods and / or scattering phenomema (e.g. Brillouin & Rayleigh scattering) can be combined in order to provide multiparameter sensing along the same fiber.

Using non-conventional fibers, such as those including Cobalt into the core,a periodic modulation of the fiber temperature can be optically induced and detected by a conventional DAS sensor. This additional feature permits to transform a conventional DAS sensor in a quasi-distributed liquid detection sensor, allowing, for example, leakage detection in long pipelines.             A. Coscetta et al. "A C-OTDR Sensor for Liquid Detection Based on Optically Heated Co2+-Doped Fibers," IEEE Sens. J., vol. 20, no. 17, pp. 10154-10158, 1 Sept.1, 2020

Using optical fiber cables already installed underground, traffic counting and classification can be realized at no additional cost. E. Catalano et al."Automatic traffic monitoring by ϕ-OTDR data and Hough transform in a real-field environment," Appl. Opt. 60, 3579-3584 (2021)

• The overall detection success rate of ALL VEHICLES is 73% (456 detected passages out of 623), while being 100% for heavy vehicles.

      E. Catalano et al."Automatic traffic monitoring by ϕ-OTDR data and Hough transform in a real-field environment," Appl. Opt. 60, 3579-3584 (2021)

BioChemical Sensors Laboratory

Biosensors “in a general sense” can be based on molecular recognition elements (MREs), which can be biological (bio-receptors such as proteins, nucleic acids, enzymes, antibodies, etc) or bio-mimetic (artificial polymers with special selective properties), such as Molecularly Imprinted Polymers (MIPs).

Optical Biosensors

• High Sensitivity;
• Real time monitoring;
• Immunity to electromagnetic interferences;
• Remote sensing capability;
• Low-cost approaches (by optical fibers); small size;
• No sparking problems.  

Optical transduction

•Refractive index (RI) sensing;

•Fluorescence emission;

• Absorbance or Chemiluminescence;

•Intensity or phase sensing.

Nanostructured Photonic Sensors Laboratory

A simple chemical optical sensor based on MIP, optical fibers and InkJet printing technology (extrinsic POF sensor)

The MIP prepolymeric mixture (200μL) is dropped on the pattern of silver nanoparticles and spun for 2 min at 1000 rpm. Thermal polymerization was then carried out for 16 h at 80 °C. The model was extracted by repeated 1 cm washings with 96% ethanol.The MIP prepolymeric mixture (200μL) is dropped on the pattern of silver nanoparticles and spun for 2 min at 1000 rpm. Thermal polymerization was then carried out for 16 h at 80 °C. The model was extracted by repeated 1 cm washings with 96% ethanol.

           
N. Cennamo, L. Zeni, M. Pesavento, S. Marchetti, V. Marletta, S. Baglio, S. Graziani, A. Pistorio, B. Andò, A Novel Sensing Methodology to Detect Furfural in Water, Exploiting MIPs, and Inkjet-Printed Optical Waveguides, IEEE Transactions on Instrumentation and Measurement 68 (2019) 1582-1589 .

Biochemical sensing exploiting plasmonic sensors based on gold nano-gratings and polymer optical fibers