High sensitivity fiber SPR sensor based on a spiral coarse cone structure.

Area of Science:

• Analytical Chemistry
• Materials Science
• Sensor Technology

Background:

• Fiber SPR sensors offer potential for rapid, portable detection of arsenic ions (As³⁺).
• Existing sensors require enhanced sensitivity, lower detection limits, and specific detection capabilities.

Purpose of the Study:

• To develop a highly sensitive and specific fiber SPR sensor for detecting As³⁺.
• To improve upon current fiber SPR sensor technology for real-world applications in water and food safety.

Main Methods:

• Implementation of a biased core fiber spiral coarse cone structure to control SPR incidence angle and reduce light modes.
• Modification of the gold film surface with glutathione (GSH) for specific As³⁺ recognition.
• Characterization of sensor performance, including sensitivity and detection limit.

Main Results:

• The proposed sensor achieved a detection sensitivity of 32.48 nm/ppb for As³⁺.
• The sensor demonstrated a low detection limit of 0.011 ppb, surpassing World Health Organization standards.
• Specific detection of As³⁺ was successfully achieved using GSH modification.

Conclusions:

• The biased core fiber spiral coarse cone SPR sensor provides a significant advancement in As³⁺ detection.
• This technology offers a feasible solution for fast, portable, and highly sensitive detection of metal ions in various matrices.
• The sensor meets stringent safety requirements for arsenic levels in drinking water and food.