Real-Time and Sensitive Immunosensor for Label-Free Detection of Specific Antigen with a Comb of Microchannel Long-Period Fiber Grating

Abstract

This study aimed to develop a comb of microchannel and immunosensor based on long-period fiber grating using the process of Lithographie Galvanoformung Abformung-like micro-electromechanical systems (LIGA-like MEMS) for real-time and label-free detection of specific antigen. The coupling between propagating core and cladding modes was conducted from the comb of microchannel long-period fiber grating (CM-LPFG). The CM-LPFG-based immunosensor consisted of a microchannel structure through photoresist stacking processes and was sandwiched with an optical fiber to obtain a long-period structure. Specific immunoglobulin against protein antigen was immobilized onto an optical fiber surface and produced a real-time resonance effect on sensing specific protein antigen from the extracted protein mixtures of the cancer cell lines. The variable transmission loss was −14.07 dB, and the resonant wavelength shift was 11.239 nm. The low limit of detection for total protein concentration was 1.363 ng/μL. Our results revealed that the CM-LPFG-based immnosensor for real-time detection of label-free protein antigen is feasible and sensitive based on the diversification of a transmission loss and achieves specific immunosensing purposes for lab-onfiber technology.

Long-Period Fiber Grating Sensors for Chemical and Biomedical Applications

“…The 3-aminopropyltriethoxysilane (APTES) silanization is a common and ideal method used in most chemical modifications of silica substrates. This method was successfully realized for the covalent immobilization of protein [ 101 , 102 ], DNA [ 67 , 68 ], antibodies [ 17 , 82 , 103 ] and so on.…”

“…Villar I. D. et al [ 133 ] proposed a simpler way to obtain a single attenuation band; the end of the fiber was coated with a silver mirror which could absorb the power transmitted through the cladding modes. More interestingly, Dey T. K. et al [ 101 ] removed a portion of the LPFG at an arbitrary location, without the requirement of precise cleaving or polishing. The unwanted resonance bands could be removed by tailoring the PMC of the cladding mode; it also benefited to enhance the RI sensitivity of this device.…”

Trace detection of canine distemper virus based on Michelson‐interferometer sensing probe

“…However, the above methods have problems such as complex operation, susceptibility to interference, harsh detection environment, and susceptibility to false positives. Optic-fiber sensors have the advantages of high sensitivity, miniaturization, telemetry, easy operation, and low cost [15][16][17], among which surface plasmon resonance (SPR) [18,19], surface-enhanced Raman scatting (SERS) [20,21], coupled micro-ring resonators [22,23], resonant diffraction grating surfaces [24,25], and optic-fiber gratings [26,27] have been used for the detection of biological samples. Guo et al achieved highly sensitive detection of urinary proteins using a tilted grating optic-fiber sensor with plasma nanocoating with the detection limit of 1.5 Â 10 À3 mg/mL [28]; Ribaut et al achieved detection of the cancer biomarker cytokeratin 17 (CK17) by using encapsulated plasma grating optical fiber with the detection limit of 10 À12 g/mL [29]; Wen et al achieved the detection of MicroRNA by using a U-shaped optic-fiber with the detection limit of 0.0133 ng/mL [30].…”

Plasmonic crescent nanoarray-based surface lattice resonance sensor with a high figure of merit

“…LSPR is the collective oscillation of free electrons in metal nanoparticles/nanostructures irradiated by incident light at a specific frequency. It is widely applied in physical, 1,2 chemical 3,4 and biological 5–7 sensing due to sensitivity to the surrounding refractive index and enhancement of the localized electric field. Meanwhile, metal nanoparticle/nanostructure-based LSPR is more suitable for integration with miniaturized platforms (especially optical fibre tip (OFT)); therefore it is possible for achieving a plug-and-play remoting sensing probe which is used in harsh and restricted environments ( e.g.…”