Applications and developments of on-chip biochemical sensors based on optofluidic photonic crystal cavities

Abstract

Photonic crystal (PC) cavities, which possess the advantages of compactness, flexible design, and suitability for integration in a lab-on-a-chip system, are able to distinguish slight variations in refractive index with only a small amount of analyte. Combined with the newly proposed optofluidic technology, PC-cavity devices stimulate an emerging class of miniaturized and label-free biochemical sensors. In this review, an overview of optofluidic PC cavities based biochemical sensors is presented. First, the basic properties of the PC, as well as the sensing principle of the PC cavity, are discussed. Second, the applications of the sensors in detecting gas, liquid, and biomolecule concentrations are reviewed, with a focus on their structures, sensing principles, sensing properties, advantages, and disadvantages. Finally, the current challenges and future development directions of optofluidic PC-cavity-based biochemical sensors are discussed.

Waveguide-based chemo- and biosensors: complex emulsions for the detection of caffeine and proteins

“…More recently, significant advancements have been made in the development of new refractive index sensing device technologies, including plasmonic resonators, 21,22 spiral waveguides, 23 optical fibers, [24][25][26] and resonant microcavities. [27][28][29] These devices have been shown to impart exceptional sensitivity, yet, practical applications are hindered by complications including a challenging replication of robust instrumental platforms, incapability to produce realtime and multiplexed signals, or expensive and complicated manufacturing.…”

Silicon‐Based Integrated Label‐Free Optofluidic Biosensors: Latest Advances and Roadmap

“…Usually, an on‐chip PhC structure consists of periodically repeating cylindrical air pores in a waveguiding slab layer (see Figure 3d). [ 137,138 ] The periodicity of the refractive index profile results in a photonic bandgap (PBG) around the operation wavelength. By introducing a local defect (e.g., missing holes), an optical resonance can be formed as a sharp peak within the bandgap.…”

Theoretical Design and Simulation Optimization of Photonic Crystal Cavity for Tetrahydrofuran Vapor Sensing

“…PC was proposed in 1987, and it is a type of optoelectronic structure with a periodic change in dielectric constant . Since its extremely small mode volume and superior quality factor ( Q ), many applications of PCs have been developed, such as filters, optical switches, and sensors . The area in which the cavity is located is capable of strongly limiting light, resulting in a PC sensor with high sensitivity .…”

“…[10] Since its extremely small mode volume and superior quality factor (Q), many applications of PCs have been developed, such as filters, [11] optical switches, [12] and sensors. [13] The area in which the cavity is located is capable of strongly limiting light, resulting in a PC sensor with high sensitivity. [14] When the surrounding environment changes the structural parameters or refractive index of PC cavity, the resonant characteristics of the PC cavity will change accordingly.…”