Lab-on-fiber SERS optrodes for biomedical applications

Stefano Managò; Giuseppe Quero; Gianluigi Zito; Gabriele Tullii; Francesco Galeotti; Marco Pisco; Andrea Cusano; Anna Chiara De Luca

doi:10.1117/12.2589841

18 April 2021 Lab-on-fiber SERS optrodes for biomedical applications

Stefano Managò, Giuseppe Quero, Gianluigi Zito, Gabriele Tullii, Francesco Galeotti, Marco Pisco, Andrea Cusano, Anna Chiara De Luca

Author Affiliations +

Proceedings Volume 11772, Optical Sensors 2021; 117720R (2021) https://doi.org/10.1117/12.2589841
Event: SPIE Optics + Optoelectronics, 2021, Online Only

Abstract

Surface-enhanced Raman scattering (SERS) has established itself as powerful tool for molecular sensing in biology and medicine. The integration of SERS systems with optical fiber is a challenging but potentially very rewarding endeavour. However, efforts to transfer the technology from the laboratory to the clinic have been frustrated by the lack of robust stable and sensitive substrates on the fiber tip, as well as the complexity of interfacing between sample and the substrate itself. Here, we propose the Lab-on-Fiber SERS optrodes, realized on the optical fiber tip by nanosphere lithography. Three types of highly ordered and reproducible SERS-active substrates have been realized: close-packed array (CPA); CPA after sphere removal (SR) and sparse array (SA) of polystyrene nanospheres, covered by a gold thin layer. To optimize the SERS probes, we compared the SERS performances in terms of Enhancement Factor (EF) and reproducibility pertaining to different patterns with different nanosphere diameters and gold thicknesses using the biphenyl-4-thiol (BPT), as target molecule. Moreover, we analysed and compared the SERS spectra of two representative biological probes, bovine serum albumin (BSA, medium molecule) and red blood cells (RBCs), in order to correlate the SERS response to the morphology and hysteric hindrance of the biological target. The SERS analysis indicated that the CPA substrate amplifies the BPT Raman intensity twice as well as the SR and SA substrates, while BSA and RBCs, with the CPA substrate, provide signals comparable to those of SR and SA substrates. Finally, we have optimized a Raman system for SERS optrode operation with efficient lighting and collection via optical fiber.

Conference Presentation

Citation Download Citation

Stefano Managò, Giuseppe Quero, Gianluigi Zito, Gabriele Tullii, Francesco Galeotti, Marco Pisco, Andrea Cusano, and Anna Chiara De Luca "Lab-on-fiber SERS optrodes for biomedical applications", Proc. SPIE 11772, Optical Sensors 2021, 117720R (18 April 2021); https://doi.org/10.1117/12.2589841

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available