We thoroughly evaluate four different taper profiles for fiber-optic surface plasmon resonance (SPR) sensors. We utilized the transfer matrix method to these profiles to evaluate their effect on key performance parameters, including sensitivity, figure of merit (FOM), detection accuracy, full-width at half maximum, amplitude dip, and half-power point. With six different metals (Au, Ag, Cu, Al, Ni, and Pt), we found that the sinusoidal taper profile with Au has the maximum sensitivity, reaching 11.9 μm/RIU at a taper ratio (TR) of 5, and a corresponding FOM of 23.36 RIU−1. In comparison, at TR=6, the exponential taper profile using Cu was able to attain a sensitivity of 25.1 μm/RIU. To optimize the sensor for visible to near-infrared applications, the results demonstrate that raising the taper ratio considerably moves the SPR dip toward longer wavelengths (e.g., from 600 to 850 nm for Au). For real-time bio-sensing applications, these findings are crucial in determining the design of high-performance, tunable SPR sensors that can detect minute changes in refractive index.
The increasing concerns regarding the health risks and economic impact of food adulteration, particularly in honey, have sparked significant attention. Ensuring the quality and authenticity of honey relies on the ability to effectively detect adulterants such as glucose. This research focuses on the utilization of etched fiber Bragg Grating (eFBG)-based sensors for monitoring honey quality and detecting cases of glucose adulteration. FBG sensors offer numerous advantages in detecting food adulteration, including their exceptional sensitivity, real-time monitoring capability, and non-invasive nature. This paper provides a comprehensive account of the experimental design and data collection procedures employed to develop FBG sensors optimized for glucose detection in honey. Furthermore, coating the eFBG sensor with reduced graphene oxide (rGO) has shown better sensitivity due to its unique properties. The achieved sensitivity found is 43.56 nm/RIU with rGO-coated eFBG sensors. The results demonstrate the ability of FBG sensors to identify honey adulterated with glucose, highlighting their potential in enhancing food safety and quality control measures.
Edible oil adulteration poses a significant threat to public health and erodes consumer trust in the food industry. This study presents an innovative approach to detect edible oil adulteration by leveraging the capabilities of Fiber Bragg Grating (FBG) sensors, known for their speed and accuracy. The FBG based sensors were employed to monitor the refractive index (RI) of edible oils (pure coconut oil), enabling the identification of adulterants introduced during the adulteration process with a lower-quality oils such as paraffin oil. Rigorous experiments were conducted to assess the reduced graphene oxide (rGO) coated FBG sensor’s efficacy in detecting adulteration. The remarkable sensitivity and specificity of the rGO-coated eFBG sensor were demonstrated through its ability to detect and measure even minute changes in RI induced by the presence of adulterants. Utilizing rGO-coated eFBG sensors yielded a sensitivity of 26.62 nm/RIU. Indicating the potential of FBG sensors to improve food safety and quality control regulations, the results exhibit the capability of these sensors to detect paraffin-adulterated coconut oil.
Food adulteration is a global concern, and developing countries are under serious threat owing to a lack of supervision and laws. Specially, milk adulterants can cause severe health risks, resulting in fatal diseases. Conventional and qualitative detection techniques are limited due to the more sophisticated way of milk adulteration and involve complexity in the processes. This paper used ultraviolet-visible-near infrared (UV-Vis-NIR) spectrophotometric measurements technique to detect the urea concentration in the milk sample. Urea concentration was taken initially at the steps of 5% and then with 10% to mix with pure milk to measure the adulteration. Results showed that the absorbance spectrum increased proportionally in the Vis and NIR regions when we increased or added the amount of urea to milk. The proposed spectrophotometry method will be a successful basis for the screening of optical wavelength to help the researcher to find out the surface plasmon resonance (SPR) phenomenon where the light and matter interaction is maximum.
In this work, mathematical models of surface plasmon resonance (SPR) biosensors are proposed. The proposed sensor with transition metal dichalcogenides (such as PtSe2) constructed of two-dimensional materials (BP and WS2). Traditional SPR biosensors are also discussed. In the field of SPR sensors, researchers have been very interested in 2-D materials. Figure of merit (F.O.M) and sensitivity are two important parts of SPR sensors, and it has been talked about with analyte ranges from 1.330 to 1.36. The proposed sensor was found to be most sensitive when it had just one layer of Platinum diselenide (PtSe2) and two layers of black phosphorous (BP). Here, a heterostructure made of BK7 Prism/Ag/PtSe2/WS2/BP is proposed as a much sensitive SPR biosensor with a Kretschmann configuration at a wavelength of 633 nm. The attenuated total reflection (ATR) method is used to measure the sensors' sensitivity, figure of merit (F.O.M.), Minimum reflections (Rmin) and detection accuracy (D.A). The proposed sensor has many uses in biomedical, chemical, and bio-sensing fields.
This paper presented a sensitivity analysis of petrol adulteration. The benzene and xylene are mainly used as adulterants in petrol because of their low cost and easy miscibility. In comparison to traditional methods, the proposed etched fiber Bragg grating (eFBG) sensor is able to detect up to low-level adulteration efficiently when coated with a TiO2 layer. Adulteration in benzene-petrol and xylene-petrol is detected using concentration mixing with 10% increments in each case. The experimental outcomes of sensitivity and Bragg wavelength shifting were studied. TiO2-coated eFBG sensors achieved the sensitivities of 6.2 nm/RIU and 5.6 nm/RIU, which is 7% and 5% enhanced as compared to bare eFBG sensors in the case of benzene-petrol and xylene-petrol, respectively. This type of sensor is well-suited for on-road use in real-time.
In the proposed work, titanium dioxide (TiO2) coated on an etched fiber Bragg grating (eFBG) sensor has been used for sensing the industrial chemicals such as glycerin. The FBGs were etched with hydrofluoric acid at a 40% concentration to interact with the outer medium before applying an optically active thin material layer for improved sensing. Raman spectroscopy and FESEM are used to characterize the sensor. An increase in the interaction of the evanescent field interacting with the analyte caused by the metal oxide layer increases sensitivity by approximately 24%. The sensitivities achieved with the bared eFBG sensor and the TiO2-coated eFBG sensor are 10.18 nm/RIU and 13.4 nm/RIU, which is better than any other earlier reported work for sensing glycerin.
In this paper, sensitivity analysis of fuel adulteration has been carried out. Kerosene is used as an adulterant due to its easy miscibility and cheap cost. It is noticed that net refractive index (RI) of adulterated diesel decreases as the kerosene level increased but reverse in the case of adulterated petrol. In our proposed sensor, we utilizes the etched Fiber Bragg Grating (eFBG) which enhanced the interaction between evanescent field and sensing medium to a greater extent. Concentration mixing is chosen in the succession of 10% in each case to detect the adulteration level in kerosene-diesel and kerosene-petrol. The experimental results of Bragg wavelength shifting and sensitivity was investigated. Sensitivity of 26.97 nm/RIU in the case diesel and 49.98 nm/RIU in the case petrol were recorded respectively. This kind of sensor is suitable for real time on-road sensing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.