Stack of nano-films on optical fiber end-face for label-free bio-recognition
Radosław Różycki-Bakon , Marcin Koba , Piotr Firek , Ewa Roźniecka , Joanna Niedziółka-Jönsson , Mateusz Jakub Śmietana
AbstractThis work presents a study on sensing capabilities of stacks of nano-films deposited on a single-mode optical fiber’s end-face for application in label-free bio-recognition. The stack consist of 5 nano-films of periodically interchanging materials characterized by different refractive indices (n at λ = 1550 nm), aluminum AlxOy (n ~ 1.58 RIU) and titanium TiOx (n ~ 2.42 RIU) oxides layers. The stack was deposited with reactive magnetron sputtering (RMS) technique. It has been found that the structures show sensitivity to refractive index of surrounding liquid (74.4 nm/RIU and 44.3 dBm/RIU) and negligible sensitivity to variations of temperature. Moreover, we show that these structures when functionalized can be used for selective detection of biological layer formation on their surface. In this work a biotin-avidin complex was used to show a label-free bio-recognition capability of the approach. Avidin concentration of 1 mg/ml induced shift of the resonance wavelength and change in reflected power by 3 nm and 0.8 dBm, respectively, when BSA which is non-specific to biotin resulted in negligible change in spectral response. The approach seems to be very interesting, especially when such advantages as batch device fabrication, sensor robustness and fully automatized stack deposition process are taken into account.
|Journal series||Journal of Lightwave Technology, ISSN 0733-8724|
|Publication size in sheets||0.5|
|Keywords in English||aluminum oxide, Fabry-Perot (FP) resonant cavity, optical fiber sensors, thin films, multi-layer structure, physical vapor deposition (PVD), reactive magnetron sputtering (RMS), refractive index sensing, titanium oxide|
|Score|| = 35.0, 11-02-2020, ArticleFromJournal|
= 35.0, 11-02-2020, ArticleFromJournal
|Publication indicators||= 6; = 4; = 6.0; : 2016 = 1.804; : 2016 = 3.671 (2) - 2016=3.35 (5)|
|Citation count*||6 (2020-08-30)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.