The Biopolymer Active Surface for Optical Fibre Sensors

Area of Science:

• Biotechnology
• Materials Science
• Optical Engineering

Background:

• Optical fiber sensors offer high sensitivity for detecting environmental pollutants and toxic agents.
• Deoxyribonucleic acid (DNA) can be utilized as a biopolymer active surface for highly specific molecular detection.
• Existing sensors require advanced materials and designs for accurate hazardous agent identification.

Purpose of the Study:

• To develop and demonstrate an optical fiber taper sensor functionalized with a DNA-surfactant complex for gas detection.
• To investigate the sensor's response to hazardous agent simulants like ammonia solution, 1,4-thioxane, and trimethyl phosphate.
• To explore the potential of biodegradable biopolymers in optical sensing devices for environmental and security applications.

Main Methods:

• Fabrication of an optical fiber taper sensor.
• Functionalization of the taper surface with a DNA-surfactant complex.
• Exposure of the sensor to specific gaseous agents and monitoring changes in optical properties.
• Analysis of light leakage and changes in the refractive index and diameter of the DNA layer.

Main Results:

• The DNA complex layer's optical properties changed upon adsorption of gaseous agents, altering the sensor's cladding.
• Changes in refractive index and layer diameter were observed, affecting light interaction within the 600-1200 nm spectral range.
• The sensor demonstrated responsiveness to ammonia solution, 1,4-thioxane, and trimethyl phosphate.

Conclusions:

• The DNA-surfactant complex-based optical fiber taper sensor is a viable approach for sensitive gas detection.
• This biodegradable biopolymer-based sensor offers a promising platform for in-line monitoring of hazardous agents.
• The technology has potential applications in environmental safety and the detection of industrial or warfare toxic agents.