Slide-type waveflex biosensor based on signal enhancement technology for alpha-fetoprotein detection

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.(c) 2023 Optica Publishing Group

Automated summary

A localized surface plasmon resonance (LSPR)-based fiber biosensor, named WaveFlex Biosensor, is proposed for accurate detection of low-concentration alpha-fetoprotein (AFP). The combination of a slide-type fiber structure and low-dimensional materials enhances the LSPR signal generated by gold nanoparticles (AuNPs), improving the sensitivity of the biosensor and enabling rapid detection. The developed fiber probe, utilizing AFP antibodies, achieves a sensitivity of 32 pm/(ng/mL) and a limit of detection of 6.65 ng/mL, demonstrating great potential for rapid and accurate AFP detection.