Abstract

The development of signal enhancement technology in optical fiber biosensors is beneficial for the accurate measurement of low-concentration samples. Here, a localized surface plasmon resonance (LSPR)-based fiber biosensor combining a slide-type fiber structure (thus named WaveFlex Biosensor) and low-dimensional materials is proposed for alpha-fetoprotein (AFP) detection. A symmetric transverse offset splicing technology was used to fabricate the multi-mode fiber (MMF–multi-core fiber (MCF)–MMF structure. Furthermore, the MMF on one side was prepared into an S-taper, forming a slide-type fiber structure to generate more energy leakage. The LSPR signal generated by gold nanoparticles (AuNPs) was enhanced by the CeO₂ NPs and C₃N quantum dots functionalized on the fiber probe. The excellent performance of NPs was conducive to improving the sensitivity of the WaveFlex biosensor and enabling the rapid detection of samples. An AFP antibody was used to identify AFP micro-biomolecules in a specific manner. Based on the combination of the above two methods, the developed fiber probe was applied to detect AFP, and the sensitivity and limit of detection were 32 pm/(ng/mL) and 6.65 ng/mL, respectively. The experimental results demonstrate that the signal-enhanced AFP WaveFlex biosensor has great potential for the rapid and accurate detection of AFP.

© 2023 Optica Publishing Group

Signal-enhanced multi-core fiber-based WaveFlex biosensor for ultra-sensitive xanthine detection

Qianqian Fu, Yiyan Xie, Feilong Gao, Wenxu Zhu, Xianzheng Lang, Ragini Singh, Bingyuan Zhang, and Santosh Kumar
Opt. Express 31(26) 43178-43197 (2023)

WaveFlex biosensor based on S-tapered and waist-expanded technique for detection of glycosylated hemoglobin

Guiwei Zhang, Ragini Singh, Bingyuan Zhang, Santosh Kumar, and Guoru Li
Biomed. Opt. Express 14(11) 6100-6113 (2023)

Humanoid-shaped WaveFlex biosensor for the detection of food contamination

Ragini Singh, Wen Zhang, Xuecheng Liu, Bingyuan Zhang, and Santosh Kumar
Biomed. Opt. Express 14(9) 4660-4676 (2023)

Plasmonic sensor based on offset-splicing and waist-expanded taper using multicore fiber for detection of Aflatoxins B1 in critical sectors

Xuecheng Liu, Ragini Singh, Muyang Li, Guoru Li, Rui Min, Carlos Marques, Bingyuan Zhang, and Santosh Kumar
Opt. Express 31(3) 4783-4802 (2023)

Humanoid shaped optical fiber plasmon biosensor functionalized with graphene oxide/multi-walled carbon nanotubes for histamine detection

Wen Zhang, Ragini Singh, Zhi Wang, Guoru Li, Yiyan Xie, Rajan Jha, Carlos Marques, Bingyuan Zhang, and Santosh Kumar
Opt. Express 31(7) 11788-11803 (2023)