Compact All-Fiber SERS Probe Sensor Based on the MMF-NCF Structure with Self-Assembled Gold Nanoparticles

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Optoelectronics

Background:

• Chronic heart failure (CHF) diagnosis relies on biomarkers like brain natriuretic peptide (BNP).
• Traditional BNP detection methods suffer from low sensitivity and poor portability.
• Novel sensor technologies are needed for accessible and accurate BNP detection.

Purpose of the Study:

• To develop a highly sensitive and portable Surface-enhanced Raman-scattering (SERS) fiber-optic sensor for brain natriuretic peptide (BNP) detection.
• To overcome the limitations of existing diagnostic methods for chronic heart failure (CHF).
• To provide a new solution for early heart failure diagnosis and biomarker detection.

Main Methods:

• A Surface-enhanced Raman-scattering (SERS) fiber-optic sensor was designed using a multimode fiber (MMF)-no core fiber (NCF) structure.
• Localized surface plasmon resonance (LSPR) and NCF's optical properties were utilized to amplify the Raman signal of toluidine blue (TB) label.
• An antibody-BNP-antibody sandwich assay was integrated with a microfluidic chip for quantitative BNP detection.

Main Results:

• The sensor demonstrated a detection limit below the clinical diagnostic threshold for BNP.
• The sensor exhibited high stability and adjustable sensitivity.
• Optimization of NCF length was performed using Rhodamine 6G (R6G) to determine optimal structural parameters.

Conclusions:

• The developed SERS fiber-optic sensor offers a stable, portable, and sensitive method for BNP detection.
• This technology presents a promising new approach for the early diagnosis of heart failure.
• The sensor has broad application prospects in the field of biomarker detection.