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Binding Analysis of Functionalized Multimode Optical-Fiber Sandwich-like Structure with Organic Polymer and Its
Daniel Jauregui-Vazquez1,2, Paulina Lozano-Sotomayor3, Jorge Emmanuel Mejía-Benavides4
1Departamento de Ingeniería Electrónica, División de Ingenierías Campus Irapuato Salamanca, Universidad de Guanajuato, Carretera Salamanca-Valle de Santiago Km 3.5 + 1.8 Km, Salamanca, Guanajuato 36885, Mexico.
This study developed a cost-effective optical fiber sensor using APTES-alginate for humidity and breath monitoring. The sensor leverages changes in refractive index due to water absorption, offering a competitive alternative for medical applications.
Area of Science:
- Materials Science
- Chemical Engineering
- Biomedical Engineering
Background:
- Chemical modification of optical fibers (OFs) enables sensor development for various analytes.
- Understanding chemical interactions is key to creating efficient, low-cost sensors.
- Existing sensors require improvement in cost-effectiveness and specificity.
Purpose of the Study:
- To theoretically and experimentally investigate organic polymeric functionalized OF structures.
- To propose a cost-effective sensor for monitoring humidity and human breath.
- To analyze the chemical interactions within the functionalized optical fiber system.
Main Methods:
- Functionalization of silicon optical fibers with (3-Aminopropyl) triethoxysilane (APTES) and alginate.
- Theoretical analysis and computational simulation of the fiber surface activation and APTES-alginate layer.
- Experimental humidity analysis to determine sensor performance metrics.
Main Results:
- Computational simulation validated surface activation and showed water absorption by alginate via electrostatic interactions.
- The OF-APTES-alginate system demonstrated a refractive index alteration upon water absorption, causing transmission power variation.
- Humidity sensing achieved a sensitivity of 3.1288 mV/RH, with response and recovery times suitable for breath analysis (50-95% RH range).
Conclusions:
- The developed OF-APTES-alginate sensor is a cost-effective alternative for humidity and breath monitoring.
- The sensor's mechanism relies on water-induced changes in the optical fiber's refractive index.
- The proposed device shows competitive performance and potential for medical applications.
