Optimization and performance analysis of SERS-active suspended core photonic crystal fibers

Abstract

Recently, surface enhanced Raman spectroscopy (SERS)-active photonic crystal fiber (PCFs) probes have gained great interest for biosensing applications due to the tremendous advantages it has over the conventional planar substrate based SERS measurements, with improvements on the detection sensitivity and reliability in measurements. So far, two main approaches were employed to get the analyte molecule in the vicinity of nanoparticles (NPs) inside PCFs in order to achieve the SERS effect. In the first case, analyte and NPs are pre-mixed and injected inside the holes of the PCF prior to the measurement. In the second approach, controlled anchoring of the NPs inside the inner walls of the PCF was achieved prior to the incorporation of the analyte. Although many studies have been conducted using one configuration or the other, no clear trend is emerging on which one would be the best suited for optimizing the biosensing properties offered by SERS active-PCF. In this paper, we investigate the performances of both configurations along with their interplays with the core size of the PCF probe. We have fabricated several samples of a standard PCF design with different core sizes, and SERS measurements of a standard Raman-active molecule are realized in the same conditions for enabling direct comparisons of the SERS intensity and measurement reliabilities between each configuration, yielding clear directions on the optimization of the SERS-active PCF probe. We envision that this study will pave the way for next-generation clinical biosensors for body fluid analysis, as it exhibits high sensitivity and excellent reliability.

Ag Nanoparticle-Decorated Graphene Oxide Coatings on the Inner Walls of Optofluidic Capillaries for Real-Time Trace SERS Detection

“…Optofluidic SERS platforms, such as capillaries or microstructure optical fibers, have been extensively studied to confine and transmit light along the fiber length for large SERS signal accumulation. The inherent fluidic channels are suitable for integrating chemical affinity function and have rarely been studied. , …”

“…The inherent fluidic channels are suitable for integrating chemical affinity function and have rarely been studied. 14,15 In this paper, we propose a capillary coated with GO/Ag nanoparticle composites (GO/Ag) as an ultrasensitive SERS substrate. GO has good water dispersibility and affinity with aromatic compounds.…”

Plasmonic Ag/ZnO Nanoscale Villi in Microstructure Fibers for Sensitive and Reusable Surface-Enhanced Raman Scattering Sensing

“…To address the above challenges, inspired by the villous ultrastructure in the small intestine, here, we developed a new optofluidic SERS platform with silver/zinc oxide nanocomposites (AZO) decorated on the inner surface of suspended-core photonic crystal fibers (SuC-PCFs). Compared with other microstructure fibers, SuC-PCFs have large cladding air holes, which are conducive for liquid injection and nanoparticle decoration . ZnO is an excellent multifunctional semiconductor material, which supports the chemical enhancement of the SERS substrate and effectively catalyzes the degradation of analytes under ultraviolet radiation. , In addition, the refractive index of ZnO is higher than that of fused silica.…”

Recent Advances in Sensing Applications of Molecularly Imprinted Photonic Crystals

“…Moreover, PhCs are combined with many technologies to improve its selectivity and sensitivity, such as surface plasmon resonance (SPR) (Gupta et al, 2016 ; Huang et al, 2020 ; Islam et al, 2020 ; Wang et al, 2020 ), surface-enhanced raman scattering (SERS) (Beffara et al, 2020 ; Dedelaite et al, 2020 ; Kraai et al, 2020 ; Wang et al, 2021 ), etc. Molecular imprinting technology (MIT) when combined with PhC sensor can be used to create biomimetic materials with specific recognition sites (Huang S. Y. et al, 2018 ; Zhao et al, 2018 ).…”