Silicon photonic crystal nanocavity-coupled waveguides for error-corrected optical biosensing

Abstract

A photonic crystal (PhC) waveguide based optical biosensor capable of label-free and error-corrected sensing was investigated in this study. The detection principle of the biosensor involved shifts in the resonant mode wavelength of nanocavities coupled to the silicon PhC waveguide due to changes in ambient refractive index. The optical characteristics of the nanocavity structure were predicted by FDTD theoretical methods. The device was fabricated using standard nanolithography and reactive-ion-etching techniques. Experimental results showed that the structure had a refractive index sensitivity of 10−2 RIU. The biosensing capability of the nanocavity sensor was tested by detecting human IgG molecules. The device sensitivity was found to be 2.3 ± 0.24 × 105 nm/M with an achievable lowest detection limit of 1.5 fg for human IgG molecules. Additionally, experimental results demonstrated that the PhC devices were specific in IgG detection and provided concentration-dependent responses consistent with Langmuir behavior. The PhC devices manifest outstanding potential as microscale label-free error-correcting sensors, and may have future utility as ultrasensitive multiplex devices.

2d Photonic Crystal Based Biosensor Using Rhombic Ring Resonator for Glucose Monitoring

“…Also higher order of sensing parameters can be achieved by this rhombic ring resonator such as resonant wavelength is in the range of 1540-1560nm, quality factor is of 178.6, 100% of transmission efficiency and sensitivity is of 1000nm/RIU. Hence the higher orders of sensing parameters are achieved in this paper which is greater than literatures reported before [14,22,[15][16][17][18][19][20][21]. The rest of the paper is organized as follows, the proposed design is explained in section 2, simulation results and discussions are reported in section 3 and section 4 concludes the paper.…”

“…The biomaterials which are suspended in a liquid medium inside nano-cavities tends to effective refractive index changes which lead to the resonant wavelength shift in the output terminal. Here the quality factor is about 4793.6nm/RIU, then transmission efficiency is about only 75% and the sensitivity is about 65.7nm/RIU [16].…”

Multi-directional ultra-high sensitive pressure sensor based on the integration of optimized double 60° bend waveguides and modified center-defect photonic crystal microcavity

“…During the past decades, PhC nanocavities with energy concentration in one-or halfwavelength cubic volume have been very beneficial for enhancing interactions between light and matters in quantum-electro-dynamic phenomenon studies [5], opto-mechanical researches [6,7], and optical sensing applications [8][9][10][11][12][13][14][15]. Recently, attributing to the rapid development of nano/micro-fabrication technologies, the optical micro-electromechanical systems (MEMS) are widely developed for various optical sensors in micro-chip scale with fine or even higher sensitivity than that conventional ones.…”

Bioengineered Surfaces for Real-Time Label-Free Detection of Cancer Cells

“…Immediately before silanization, surfaces are cleaned with oxidant media to remove organic pollutants and to increase the hydroxyl moieties on the surface [35]. The used oxidant is piranha solution [36][37][38][39], consisting of a concentrated sulfuric acid mixed with hydrogen peroxide at 3:1 ratio. This treatment is performed by heating for 30 min only.…”