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The present study has been performed with the purpose of designing a highly sensitive biosensor for cervical cancer cell detection. The structure of the proposed design for biosensor includes a hollow core, four-quarter circular-type airholes spread through the cladding region, and Zeonex (R.I.-1.53) as background fiber material. Further, guiding properties of the proposed waveguide have been studied. The suggested photonic crystal fiber structure has been operated in the THz frequency regime. COMSOL Multiphysics 5.6a software based on finite element method and MATLAB 17b software have been used to examine various guiding properties of the sensor. Various performance parameters such as effective refractive index 1.3414, effective area 8.4733 × 10−9 µm2, nonlinearity 9.9468W−1 km−1, propagation constant 2.5703 × 10−26, relative sensitivity 78.68%, and confinement loss 5.1406 × 10−26 cm−1 have been evaluated for cervical cancer cells. The simplified design reduces fabrication complexity and makes it cost-effective. It enhances the optical sensing capabilities of the proposed sensor model. The proposed design will add new opportunities in the field of bio photonics. Moreover, it leads to better applications in medical field for detecting and diagnosing cervical cancer cells disease. [ABSTRACT FROM AUTHOR]

In the present study, an ultra-sensitive surface plasmon resonance biosensor is developed. The device is composed of a CaF2-prism, silver, silicon nitride, nickel, and black phosphorus have been deposited. The setup is grounded in the Kretschmann configuration and theoretically analyzed by means of transfer matrix method and Fresnel equations. For selective diagnosis of liver tissue and its mutation in terms of variation in RI, the biosensor provides an ultrahigh angular sensitivity of 383.62°/RIU for MET tissue and 403.92°/RIU for HCC tissue. The optimization of angular sensitivity and other sensor parameters in terms of thickness and number of layers has also been utilized. To validate the reflectance curve, electric field intensity enhancement factor and phase interrogation have also been conducted. The acquired results state that the proposed biosensor yields an enhanced sensitivity when compared to other reported results. Due to its advantage of fast, accurate and early-stage detection of liver mutations with a very small number of samples, this report may expedite a sensing device for commercial applications. [ABSTRACT FROM AUTHOR]

A novel design of an optical refractive index sensor based on surface plasmon resonance (SPR) has been offered in the article. The structure of the sensor is grounded on a Kretschmann configuration which comprises of CaF2 prism, silver (Ag) metal, beryllium oxide (BeO) nanomaterial, Nickel (Ni), and a heterostructure 2D nanomaterial (blue phosphorene/tungsten diselenide; BP/WS2). The analyte has been sensed on the 2D heterostructure material surface to examine the change in refractive index (RI). For prudent examination of the reflectivity of the proposed sensor, the transfer matrix method (TMM) has been employed. The optimization of sensitivity in terms of thickness and number of layers has also been investigated. Electric field intensity enhancement factor and phase interrogation parameters and normalized electric field distribution have also been utilized to validate the resonance angle position and to justify ultrahigh sensitivity. Utilizing the 2D nanomaterials intensifies the sensitivity of the proposed structure up to 401.2° per refractive index unit (deg/RIU). The FoM and detection accuracy (DA) is optimized up to 178.31 RIU−1 and 0.444 deg−1 respectively. The sensor offers a simple and selective structure with efficient cost and thickness. Additionally, the advantage of being real-time, stable, and label-free detection of an analyte sample with a very small amount of sample makes the proposed sensor a competing technology to be fabricated as a sensor chip for commercial applications. [ABSTRACT FROM AUTHOR]

The present work has been performed with an intent of designing a robust, profound, and highly sensitive sensor for numerous explosive detections. The main objective of the present study is to design a simplified structure with fabrication feasibilities. The proposed structure of an explosive detector includes a hollow core surrounded with four sectored-type air holes in the cladding area and silica as background of the fiber which operates for 1–2 THz frequency band. Furthermore, the optical guiding property of the detector is examined, and numerical study has been performed. The modelling has been performed with the help of COMSOL Multiphysics 5.6a software based on finite element method, and Origin 2023 software is used for plotting and analyzing the characteristic curves. The suggested sensor structure has been analyzed for various explosives such as TNT, RDX, HMX, and PETN. Optical parameters such as effective refractive index, confinement loss, effective area, nonlinearity, propagation constant, and relative sensitivity have been evaluated. The proposed structure offers relative sensitivity of 84.02%, 69.42%, 71%, and 79.31% for TNT, RDX, HMX, and PETN samples, respectively. The proposed detector structure offers better sensing proficiency for explosive detection. The simplified design favors the fabrication possibilities and makes it economically effective. The proposed study will add up to the developments in the field of photonics and chemical detection and, moreover, will open new doors for better application for security and explosive sensing. [ABSTRACT FROM AUTHOR]

A novel surface plasmon resonance-based biosensor for SARS-CoV-2 virus is proposed in this article. The biosensor is a Kretschmann configuration-based structure that consists of CaF2 prism as base, at which silver (Ag), TiO2, and MXene nanolayers are used to enhance the performance. Theoretically, the performance parameters have been investigated by means of Fresnel equations and transfer matrix method (TMM). The TiO2 nanolayer not only prevents oxidation of Ag layer but also enhances the evanescent field in its vicinity. The sensor provides an ultrahigh angular sensitivity of 346°/RIU for the detection of SARS-CoV-2 virus. Some other performance parameters, including FWHM (full width at half maxima), detection accuracy (DA), limit of detection (LOD), and quality factor (QF) have also been calculated for proposed SPR biosensor with their optimized values 2.907°, 0.3439 deg−1, 1.445 × 10−5, and 118.99 RIU−1, respectively. The obtained results designate that the proposed surface plasmon resonance (SPR) based biosensor has notably enhanced angular sensitivity as compared to previous results reported in the literatures till date. This work may facilitate a significant biological sample sensing device for fast and accurate diagnosis at early stage of SARS-CoV-2 virus. [ABSTRACT FROM AUTHOR]

A highly sensitive surface plasmon resonance biosensor employing BK7 prism, Silver (Ag), zinc oxide (ZnO), ferromagnetic material (Fe2O3), and two-dimensional (2D) nanomaterial black phosphorous (BP) has been proposed. Thin layers of two different oxide layers sandwiched between Ag and BP in Kretschmann configuration. The angular interrogation method–based numerical simulation is applied for modelling of high performance SPR biosensor at a wavelength of 633 nm (visible region). Transfer matrix method and finite element methods have been used to obtain [performance parameters. This sensor can detect malaria at different stages and provides a large range of refractive index (RI) sensing from 1.369 to 1.409. The RI for malaria stages, including the ring, trophozoite, and schizont stages, are 1.396, 1.381, and 1.371 respectively, with corresponding angular sensitivities of 367 deg/RIU, 297 deg/RIU, and 269 deg/RIU. The sensor offers an ultrahigh angular sensitivity for malaria detection in ring stage. This research could pave the way for an important bio sample detection apparatus that allows for quick and precise in ring stage diagnosis. [ABSTRACT FROM AUTHOR]

The extant work exhibits a unique design of surface plasmon resonance (SPR) which has been suggested for indications of different malarial disease stages. The device construction is founded on the Kretschmann configuration and consists of multiple layers, including BK7 prism, silver (Ag) metal layer, zinc oxide (ZnO), lead titanate (PbTiO3), and a heterostructure 2D nanomaterial (black phosphorus; BP) at the top. The angular reflectivity is evaluated using TMM stands for transfer matrix method. The thickness and number of layers have been studied for the optimization of sensitivity. Additionally, normalized electric field distribution, electric field intensity enhancement factor, and phase interrogation parameters have been applied to validate the position of occurrence of resonance angle and ultrahigh sensitivity. The equivalent angular sensitivity for the refractive indices of different stages of malaria infection (ring stage, trophozoite stage, and schizont stage) are 1.396, 1.381, and 1.371 for which the angular sensitivity is 387°/RIU, 305°/RIU, and 273°/RIU respectively. The suggested SPR sensor performs transcendentally when it comes to ring stage detection and corresponding quality factor of 107.12RIU-1 and detection accuracy of 0.27 deg-1. The sensor design can be crucial for future adavncement and practical implimentation of biosensors. [ABSTRACT FROM AUTHOR]

A surface plasmon resonance–based biosensor for the detection of chikungunya virus has been proposed in this article. The structure of the sensor is based on the Kretschmann configuration, which includes a BK7 prism, silver (Ag) metal, titanium dioxide (TiO2), a perovskite material (BaTiO3), and a heterostructure 2D nanomaterial (blue phosphorene/tungsten disulfide; BP/WS2). The surface of the 2D heterostructure material is employed for the detection of the analyte, aiming to investigating the alterations in refractive index. Using the transfer matrix method (TMM), the reflectivity of the proposed sensor is analyzed numerically. The investigation also explores the enhancement of sensitivity by considering variations in number and thickness of layers. To confirm the location of resonance angle and substantiate the ultrahigh sensitivity, an examination of the electric field intensity enhancement factor and normalized electric field distribution has been also conducted. The optimization of parameters for the proposed sensor revealed that platelets and plasma cells have a maximum sensitivity of 365°/RIU and 152°/RIU, figures of merit of 94.147 and 73.98, and detection accuracy of 0.2579 and 0.4859 deg−1. The normalized electric field plot suggests a penetration depth of the order of 102 nm which enables long-range sensing and strong field-analyte interaction. The sensor offers high sensitivity and stability and may find useful applications in biomedical industries. [ABSTRACT FROM AUTHOR]