Sensitive Surface Plasmon Resonance Research Articles

Direct electronical readout of surface plasmon resonance biosensor enabled by on-fiber Graphene/PMMA photodetector

Surface plasmon resonance (SPR) optical fiber sensors are appealing for biomolecular detection due to their inherent characteristics such as flexibility, real-time performance, and high sensitivity. Concurrently, incorporating SPR sensors into wearable devices has emerged as a significant strategy. However, the majority of traditional SPR optical fiber sensors utilize spectrometers for optical readout, which leads to a relatively bulky overall size of the sensing system. Herein, we present the first optical fiber device capable of conducting sensitive SPR measurements and providing direct electronical readout. This has been achieved by integrating a hyperbolic-metamaterial SPR (HMM-SPR) sensor with an on-fiber graphene/PMMA photodetector (oFGPD). The HMM, composed of three pairs of Au/ZrO2, has been employed to develop highly sensitive SPR sensors. The oFGPD, which was constructed by transferring a single layer of graphene onto a tapered fiber region and subsequently covering it with a PMMA protecting film, achieved a high responsivity of 3.42 × 106 A W−1 (at 14.07 pW) and a rapid response time of approximately 90 ms at 1550 nm. More significantly, we have incorporated an SPR sensor based on a side-polished fiber (SPF) into the oFGPD, enabling an electronical readout technique for environmental refractive index (RI) SPR signals in a broad potential spectral range, from visible to near-infrared, all within a more compact device. This integration has been successfully validated in the detection of urea and glucose concentrations in artificial perspiration. This approach provides a novel direction for SPR sensor detection and establishes a solid foundation for their application in wearable technology.

A Review Study on Molecularly Imprinting Surface Plasmon Resonance Sensors for Food Analysis

Surface plasmon resonance (SPR) sensors have emerged as a powerful tool in biosensing applications due to their ability to provide sensitive and real-time detection of chemical and biological analytes. This review focuses on the development and application of molecularly imprinted polymer (MIP)-based SPR sensors for food analysis. By combining the high selectivity of molecular imprinting techniques with the sensitivity of SPR, these sensors offer significant advantages in detecting food contaminants and other target molecules. The article covers the basic principles of SPR, the role of MIPs in sensor specificity, recent advancements in this sensor development, and food applications. Furthermore, the potential for these sensors to contribute to food safety and quality control was explored, showcasing their adaptability to complex food matrices. The review concluded the future directions and challenges of SPR-MIP sensors in food analysis, emphasizing their promise in achieving high-throughput, cost-effective, and portable sensing solutions.

An Optimized Graphene-Based Surface Plasmon Resonance Biosensor for Detecting SARS-CoV-2

Graphene-enhanced surface plasmon resonance (SPR) biosensors offer promising advancements in viral detection, particularly for SARS-CoV-2. This study presents the design and optimization of a multilayer SPR biosensor incorporating silver, silicon nitride, single-layer graphene, and thiol-tethered ssDNA to achieve high sensitivity and specificity. Key metrics, including SPR angle shift (Δθ), sensitivity (S), detection accuracy (DA), and figure of merit (FoM), were assessed across SARS-CoV-2 concentrations from 150 to 525 mM. The optimized biosensor achieved a sensitivity of 315.91°/RIU at 275 mM and a maximum Δθ of 4.2° at 400 mM, demonstrating strong responsiveness to virus binding. The sensor maintained optimal accuracy and figure of merit at lower concentrations, with a linear sensitivity response up to 400 mM, after which surface saturation limited further responsiveness. These results highlight the suitability of the optimized biosensor for real-time, point-of-care SARS-CoV-2 detection, particularly at low viral loads, supporting its potential in early diagnostics and epidemiological monitoring.

Polarization modulated spectroscopic ellipsometry-based surface plasmon resonance biosensor for E. coli K12 detection

In this work, we report on the application of the polarization modulated spectroscopic ellipsometry-based surface plasmon resonance method for sensitive detection of microorganisms in Kretschmann configuration. So far, rotating analyzer and single wavelength polarization modulation methods have widely been investigated for phase sensitive surface plasmon resonance measurement. In this study, a much simpler optical setup relying on fast electro-optic phase modulator crystals is introduced for bacteria detection. A beta barium borate crystal connected to a function generator is adapted for generating phase shifts in the millisecond regime to extract the ellipsometric angles (Ψ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Psi$$\\end{document} and Δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Delta$$\\end{document}) under the surface plasmon resonance condition. For detection, the gold surface was functionalized with anti-Escherichia coli antibodies, and E. coli K12 was attached to them. We show that polarization modulated spectroscopic ellipsometry achieves a refractive index resolution in the order of 10-5\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$10^{-5}$$\\end{document} RIU, and a limit of detection of 102\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$10^{2}$$\\end{document} CFU/mL for E. coli K12 which is compatible with other surface plasmon resonance based phase sensitive methods with more complex detection concepts. As a follow-up step, an optical model can be developed to enhance this biosensor’s performance, and applications for sorting and detecting other biological targets will be investigated.

Ultra high sensitive long range surface plasmon resonance sensor for chemical and biochemical sensing

In this work, we proposed a long-range surface plasmon (LRSPR) sensor using a dielectric (Cytop) –Gold (Au)- graphene oxide (GO) layer to enhance the sensor’s detection accuracy (DA), figure of merit (FoM) and imaging sensitivity (Simag). The proposed sensor’s effectiveness for long-range is numerically demonstrated. The GO layer is used to protect the unwanted oxidation of Au and to improve the imaging sensitivity. By comparing its FoM and Simag to that of the traditional surface plasmon sensor (cSPR), the proposed sensor takes advantage of its high adsorption efficiency and high resolution. The Au-GO layer in the cSPR sensor and the cytop-Au-GO layer in the proposed sensor interfaces enhance the electric field intensity and penetration depth (PD). We attain the highest DA, FoM and Simag of 100/°, 1400/RIU, and 4183.9/RIU with 2000 nm of cytop thickness. For chemical and biological applications, the proposed LRSPR sensor design may be advantageous.

Ultrahigh Sensitivity Surface Plasmon Resonance Magnetic Field Sensor Based on Side-Core Inscribed Capillary Fiber

Ultrahigh Sensitivity Surface Plasmon Resonance Magnetic Field Sensor Based on Side-Core Inscribed Capillary Fiber

Sensitivity-enhanced plasmonic sensor modified with ZIF-8

ZIF-8 is a typical metal–organic framework (MOF) material, which has great potential for sensor improvement. In this paper, we prepared a high sensitivity surface plasmon resonance (SPR) sensor based on ZIF-8/Au and described the preparation process of the sensor and characterized the samples in detail. The results showed that the synthesized ZIF-8 nanoparticles were uniform with an average diameter of about 50 nm. The performance of the sensor was related to the amount of ZIF-8, which could be controlled by adjusting the number of spin-coating cycles. When the refractive index ranged from 1.3335 to 1.3635, the maximum sensitivity of the sensor reached 3961.36nm/RIU with one cycle of spin-coating, which was 74.05% higher than that of pure Au single-layer film sensor. Furthermore, the feasibility of the proposed sensor for biological sensing was demonstrated by detecting bovine serum albumin (BSA).

A study of highly sensitive surface plasmon resonance biosensor for the detection of SARS-CoV-2 virus

A study of highly sensitive surface plasmon resonance biosensor for the detection of SARS-CoV-2 virus

High sensitivity fiber optic SPR sensor for selenium ion concentration detection

Balance of selenium content is of great significance to human health, and there is a need for rapid and sensitive detection of selenium ion concentrations in the human body and food. This article proposes a highly sensitive fiber surface plasmon resonance (SPR) sensor for selenium ion concentration detection. By fabricating a fiber U-shaped ring composite structure and modifying Cu3VSe4 material, the sensitivity of the fiber SPR sensor is improved to 6826.82 nm/RIU. Using 2,4-diamino-6phenyl-1,3,5-triazine to modify the surface of the sensor to achieve specific detection of selenium ion concentration. The experiment results indicate that the detection sensitivity of the sensor is 1.858 nm/(lg(pg/ml)) with range of 100 pg/ml to 1 μg/ml, and the LOD is 124.06 pg/ml. The highly sensitive SPR sensor proposed in this article, without labeling, can achieve high sensitivity and rapid detection of selenium ions, providing a new approach for trace element content detection.

Evaluation of reflective fiber-optic surface plasmon resonance sensor for monitoring scale deposition.

A reflective surface plasmon resonance (SPR) sensor was evaluated for real-time monitoring of scale deposition. The sensor consists of an optical fiber, only 5mm at the gold-coated tip of the sensing area. The effect of silica growth on the sensor response was evaluated using a Na2SiO3 solution. The sensitivity of the sensor to silica was 1.6 ± 0.3nm per one immersion in the solution of 1000mg/L (as SiO2) at 85°Cand subsequnt air drying, as indicated by theSPR peak shift. The amount of silica deposited on the gold surface was measured by the quartz crystal microbalancemethod, and the SPR sensitivity of 0.089nm/ng to silica mass was obtained. The detection limit (3σ) of the SPR sensor was 17ng, correspondingto a thickness of 2.5nm for amorphous silica. The SPR sensor wastested in geothermal brine sampled at the Sumikawa Geothermal Power Plant, where a clear SPR shift was observed, suggesting the effectiveness of the SPR sensor for scale monitoring.

A Highly Sensitive D-Shaped PCF-SPR Sensor for Refractive Index and Temperature Detection.

A novel highly sensitive D-shaped photonic crystal fiber-based surface plasmon resonance (PCF-SPR) sensor for dual parameters of refractive index and temperature detecting is proposed. A PCF cladding polishing provides a D-shape design with a gold (Au) film coating for refractive index (RI) sensing (Core 1) and a composite film of silver (Ag) and polydimethylsiloxane (PDMS) for temperature sensing (Core 2). Comsol Multiphysics 5.5 is used to design and simulate the proposed sensor by the finite element method (FEM). The proposed sensor numerically provides results with maximum wavelength sensitivities (WSs) of 51,200 and 56,700 nm/RIU for Core 1 and 2 as RI sensing while amplitude sensitivities are -98.9 and -147.6 RIU-1 with spectral resolution of 1.95 × 10-6 and 1.76 × 10-6 RIU, respectively. Notably, wavelength sensitivity of 17.4 nm/°C is obtained between -20 and -10 °C with resolution of 5.74 × 10-3 °C for Core 2 as temperature sensing. This sensor can efficiently work in the analyte and temperature ranges of 1.33-1.43 RI and -20-100 °C. Due to its high sensitivity and wide detection ranges, both in T and RI sensing, it is a promising candidate for a variety of applications, including chemical, medical, and environmental detection.

Highly sensitive SPR based PCF sensor for broader analyte detection range including blood compositions detection

In this manuscript, a photonic crystal fiber (PCF) based sensor working on surface plasmon resonance (SPR) concept, which is polished at both the sides and consisting of semi-circular grooves is presented for the detection of a broad range of analytes with refractive index (RI) from 1.17 to 1.40. Also, the analysis is carried out for the diagnosis of different blood compositions such as water, plasma, white blood cells (WBCs), hemoglobin (HB) and red blood cells (RBCs). Plasmonic material gold is coated in the semi-circular grooves, which causes the strong SPR effect due to reduced distance between core and analyte resulting in excellent detection of the analytes. Thus, the optimum wavelength sensitivity and resolution in the case of broad analyte range detection with RI from 1.17 to 1.40 is obtained as 13000 nm/RIU and 7.7×10−6 RIU respectively. Also, blood composition detection using the proposed sensor results in excellent sensing performance with the maximum wavelength sensitivity for hemoglobin-RBCs as 11,500 nm/RIU with finer resolution of 8.69×10−6 RIU.

Enhanced Ultra-High Sensitivity Surface Plasmon Resonance Refractive Index Sensor Based on Black Phosphorus and Corrugated Silver Layer Structure

Enhanced Ultra-High Sensitivity Surface Plasmon Resonance Refractive Index Sensor Based on Black Phosphorus and Corrugated Silver Layer Structure

Design and Development of High Sensitive Surface Plasmon Resonance Biosensors for Glucose Detection

Design and Development of High Sensitive Surface Plasmon Resonance Biosensors for Glucose Detection

Nanozyme-triggered polymerization amplification strategy for constructing highly sensitive surface plasmon resonance immunosensing

Nanozyme-triggered polymerization amplification strategy for constructing highly sensitive surface plasmon resonance immunosensing

Highly sensitive surface plasmon resonance sensor based on the anti-resonant fiber with six nested tubes

On the heels of the continuous development of optical fiber sensing technology, optical fiber sensors based on surface plasmon resonance (SPR) have attracted widespread attention. Herein, an SPR sensor based on the six nested anti-resonant fiber (ARF) is designed and analyzed by the finite element method (FEM). All the structural parameters are optimized to achieve high-sensitivity liquid refractive index detection. Filling the anti-resonant tube with plasmonic materials to excite SPR can further reduce the manufacturing complexity. The optimal ARF-SPR sensor has excellent characteristics, including an average wavelength sensitivity of 42,000 nm/RIU, maximum sensor length of 0.08 cm, and resolution of 1.61×10−6RIU. The ARF-SPR sensor has great potential in chemical analysis, biomedicine, and other fields.

Development of surface plasmon resonance sensor utilizing GaSe and WS2 for ultra-sensitive early detection of dengue virus

This manuscript introduces highly sensitive surface plasmon resonance (SPR) sensor for early detection of the dengue virus. Through extensive optimization using MATLAB, the sensor architecture is meticulously constructed with a BK7 prism, Copper (Cu) layer, Gallium selenide (GaSe), Tungsten disulphide (WS2), and a sensing medium (SM) containing blood components (infected platelets and normal platelets) to ensure optimal performance. Use of WS2 emerges as a highly effective biomolecular recognition element (BRE) layer, leading to exceptional sensor capabilities. The proposed sensor achieves a peak sensitivity (S) of 303.28 (˚/RIU) and a resonance angle shift (∆θres.) of 10˚ specifically during the detection of infected platelets. Computational modeling using COMSOL Multiphysics validates the ability of the sensor to generate an intense electric field with a magnitude of 1.68×105 (V/m) and a penetration depth (PD) extending to 153.24 nm in the SM. This unique combination of PD and enhanced performance parameters positions the proposed SPR biosensor as a promising tool for the early-stage detection of the dengue virus.

Numerical analysis of a single channel exposed core elliptical shaped PCF based highly sensitive SPR sensor for wide RI sensing.

This study presents a numerical study of a highly sensitive photonic crystal fiber (PCF) surface plasmon resonance (SPR) sensor capable of detecting five types of cancer and bacterial contamination in water. By precisely arranging only two air holes in a single channel of an elliptical-shaped PCF, the sensor maximizes interaction between core-guided modes and surface plasmon polaritons (SPP) along the fiber. Evaluation using COMSOL Multiphysics simulation software, based on finite element method (FEM), demonstrates outstanding sensor performance across a wide refractive index (RI) range (1.33 to 1.43). With a maximum wavelength sensitivity (WS) of 188,000 nm/RIU and amplitude sensitivity (AS) of -22,377.99 RIU-1, the sensor achieveStructural Design and Methodologys a sensor resolution (SR) of 5.3191 × 10-7 RIU and figure of merit (FOM) of 854.55 RIU-1. Notably, it exhibits AS and WS values tailored for specific cancer cell types and water contamination. These results endorse the sensor's potential in diverse biological and molecular analyte RI detection applications within the visible to near-infrared (VNIR) range (0.55 to 4 µm), offering high sensitivity, affordability, wide sensing range, good linearity, low propagation loss, and simplicity in construction.

6-benzylaminopurine highly sensitive analysis by SPR sensor with bifunctional magnetic molecularly imprinted polymers nanoparticles

A highly sensitive Surface Plasmon Resonance (SPR) sensor coupled magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) was developed and validated for the determination of 6-benzylaminopurine (6-BA) in vegetables. MMIPs NPs were synthesized using methacrylic acid (MAA) and sodium p-styrene sulfonate (SSS) as functional monomers. The SPR exhibited a linear dependence on 6-BA concentration in the range 5–300 pg/mL with a low limit of detection (3.02 pg/mL) and limit of quantitation (10.08 pg/mL). The SPR signal of 6-BA-captured MAA/SSS-MMIPs NPs is higher than those of the structural analogues (6-KT and 2-IP: 1.72 and 2.12 times) and the non-structural analogues (2, 4-D and NAA: 2.31 and 2.57 times), indicating the SPR sensor has good selectivity for 6-BA. The recovery of the established method was between 93.8% and 108.6% with a coefficient of variation less than 9.2% in four vegetables. This SPR sensor shows great potential in detecting 6-BA in more vegetables.

Sensitivity enhancement in erbium-doped fiber laser intra-cavity SPR sensor

To enhance sensitivity of fiber-based surface plasmon resonance (SPR) sensor for refractive index detection, we propose a concept of fiber laser intra-cavity SPR sensor that is constructed by placing a hollow fiber-based SPR sensor in an erbium-doped fiber laser cavity. The hollow fiber-based SPR sensor is firstly designed and optimized to achieve maximum amplitude sensitivity of 65.576 RIU−1 in a detection range of 1.6–1.61 at the operation wavelength of 1530 nm, and then placed in the erbium-doped fiber laser cavity to form the fiber laser intra-cavity SPR sensing system. The relationships between the detection sensitivity, pump power, and SPR sensor length of the laser intra-cavity SPR sensor are investigated in detail by using three-level rate equations, and the numerical results demonstrate that the sensitivity is enhanced 82 times, achieves 5375.627 RIU−1 when the fiber-based SPR sensor is placed in the laser cavity, and can be further enhanced by tuning the pump power to close to threshold value. The work described here demonstrates a possible solution to enhance the sensitivity by combining the fiber-based SPR sensor and the fiber laser.