Copyright © 2022 Foshan MBRT Nanofiberlabs Technology Co., Ltd All rights reserved.Site Map
Optical gas sensors play a vital role in monitoring multiple gases simultaneously and have a wide range of applications in healthcare and environmental monitoring. Due to the urgent need for optical gas sensors in various fields such as environmental monitoring, healthcare, industrial and clinical areas, a number of gas sensor devices have been proposed for the detection of specific gases such as oxygen, carbon dioxide and ammonia. Several analytical methods have been used in evaluating the performance of optical gas sensors, such as fluorescence burst, phase shift, wavelength shift, and fluorescence lifetime changes due to fluorescence resonance energy transfer (FRET).
The main point of this paper
Development of coaxial electrospinning technology:
Coaxial electrospinning technology is an innovative, versatile, and cost-effective method for the simultaneous integration of multiple fluorescent dyes in polymer matrices
Introduced by Loscertales et al. in 2002, the technology encapsulates water in oil droplets through a coaxial electrospinning device, and Sun et al. successfully fabricated core-shell fibres in 2003
Coaxial electrospinning technology can produce nanofibres with various morphologies of shell-core structure, such as ribbon fibres, hollow fibres, tubulo-wire nanofibres, etc.
Advantages of coaxial electrospinning:
Coaxial electrospinning can solve the problem of preparing nanofibres from certain non-spinable polymers by using difficult and non-spinable polymers as the core layer and materials with good spinning properties as the shell layer.
The technology is capable of preparing integrated fibres from two or more raw materials with different physical and chemical properties, and can adjust, modify, reconfigure, dope and functionalise the core layer materials.
Preparation and performance evaluation of O2 and NH3 gas sensors:
In this study, fibre-optic dual sensors were fabricated using the coaxial electrospinning method for the simultaneous detection of O2 and NH3 gases by selecting the O2-sensitive dye PtTFPP and the NH3-sensitive dye Eosin Y
The performance of the optical sensors was evaluated by fluorescence burst analysis and wavelength shift measurements, which allow estimating the concentration of free monomers in equilibrium with the micelles, and thus assessing the performance of the sensor
The application of the sensors is promising:
Sensors prepared by coaxial electrospinning technology have good prospects for biomedical and other applications, especially in the development of innovative optical sensing membranes
The successful implementation of this technique depends on the effective control of three key parameters in the process, including the nature of the polymer matrix solution, the surrounding environmental conditions and variable operating factors
Technical Application:
Coaxial electrospinning is used in the field of medical devices and sensor technology.
Novel optical dual sensor:
The sensor can detect oxygen (O2) and ammonia (NH3) simultaneously.
Sensor preparation:
Core-shell fiber membranes doped with fluorescent dyes are produced by coaxial electrospinning.
The polymer matrix cellulose acetate (CA) is dissolved with the O2 sensitive dye platinum (II)-tetrakis (pentafluorophenyl) porphyrin (PtTFPP) and the NH3 sensitive dye Eosin-Y respectively.
Sensor structure:
The O2 sensitive dye PtTFPP is located in the core layer, and the NH3 sensitive dye Eosin-Y is located in the shell layer.
Detection principle:
The UV LED illuminates the sensor and monitors the intensity change and wavelength shift in the presence of gas.
Sensitivity:
The sensitivity of O2 and NH3 is 6.4 and 3.2, respectively.
Response and recovery time:
The response and recovery time of the O2 sensor probe are 12 seconds and 29 seconds, respectively.
The response and recovery times of the NH3 sensor probe are 65 seconds and 66 seconds respectively.
A novel optical dual sensor with a core (O2) and shell (NH3) fiber structure was easily fabricated using a coaxial electrospinning method, demonstrating the ability to simultaneously sense ammonia and oxygen in laboratory measurements. The nanofiber structure fabricated by this method significantly enhanced the sensing performance, improving linearity, response, and recovery capabilities. The experimental results showed that the optical dual sensor had sensing sensitivities of 6.4 and 3.2 for oxygen and NH3, respectively. The response and recovery times of the oxygen and NH3 sensors were 12 s/29 s and 65 s/66 s, respectively. In addition, a novel and unique detection method was discovered by using Eosin-Y sensitive dye for wavelength shift measurement, which has never been discussed before. Therefore, this method is expected to be a viable candidate for the fabrication of optical dual sensors with a wide range of applications.
