查找使用阿拉丁产品的科研文献

MoS2-Graphene heterostructure enhanced fiber optic SPR sensor for highly sensitive glucose detection

Jiaming Ma,Ridong Wang,Dachao Li,Kexin Xu

Fiber-optic surface plasmon resonance (FO-SPR) sensors, known for the advantages in miniaturization, label-free, and high flexibility, are promising for continuous glucose monitoring. However, due to limited sensing area, FO-SPR sensors exhibit relatively lower sensitivity compared to prism-based SPR sensors. To address this issue, a novel FO-SPR sensor modified with a molybdenum disulfide (MoS 2 )-graphene heterostructure was proposed in this paper. The sensitivity was evaluated both theoretically and experimentally, which showed that the highest sensitivity was achieved with two layers of MoS 2 and two layers of graphene. Moreover, pyrene-1-boronic acid (PBA) was bound to the heterostructure to improve specificity for glucose molecules. It was found that the sensitivity was also further improved by using PBA, and total enhancement of heterostructure and PBA reached 1229.29 % compared to the sensor modified with only a gold film. The newly proposed FO-SPR sensor achieves a sensitivity of up to 12593.06 nm/RIU for glucose concentrations in the range of 0–500 mg/dL, indicating its potential for widespread application in glucose concentration measurement.

Reflective Optical Fiber SPR Sensor for Simultaneous Measurement of Glucose Concentration and Temperature

Li Zhoujie,Liu Ting,Lin Zhipeng,Liu Jie,Song Zhaojun

To achieve a compact and robust structure, a reflective optical fiber surface plasmon resonance (SPR) sensor is proposed for the simultaneous measurement of glucose concentration and temperature. The fiber probe uses the multimode optical fiber-single mode optical fiber-multimode optical fiber (MSM) heterojunction structure, in which the region with a gold film is used to sense glucose concentration, while the other region with a gold film and a polydimethylsiloxane@gold (PDMS@Au) composite is used to sense temperature. A silver film for light signal reflection is coated on the end face of the fiber probe to improve the signal-to-noise ratio (SNR). The sensor successfully overcomes cross-sensitivity and achieves sensitivities of 3.05 nm/% and − 1.69 nm/°C for glucose concentration and temperature, respectively. The proposed sensor can realize high-precision sensing of glucose and other biological analytes with temperature compensation. In addition, the reflective sensing structure makes the system compact and flexible, which enables remote detection and in-situ monitoring. The proposed sensor has a wide range of applications in the fields of food safety, biochemistry, and environmental monitoring.

Research on three-channel detection based on M-shaped SPR fiber optic sensor

Hua-Long Du,Qi Wang

This study presents a novel surface plasmon resonance (SPR) sensor utilizing an M-shaped optical fiber structure, which enables the simultaneous detection of temperature, pH, and refractive index (RI). The sensor is made of multi-mode fiber, the whole M-shaped fiber without any splicing, which ensures the stability of the sensor's performance and structure. The entire fiber surface is coated with a 50 nm thickness Au film to stimulate the SPR phenomenon. The M-shaped fiber sensor consists of three U-shaped sensing regions coated with indium tin oxide (ITO), polydimethylsiloxane (PDMS)/Au nanoparticles (Au-NPs), and polyacrylic acid (PAA)/chitosan (CS) composite films for RI, temperature, and PH detection in different detection regions. The sensor excels in performance with RI sensitivity up to 4459 nm/RIU within the scope of 1.3332-1.3452, temperature sensitivity of -1.65 nm/°C in the interval of 25-65°C, and pH sensitivity of -21.12 nm/pH lying within the interval of 5.45-9.55. Additionally, the sensor exhibits good stability and repeatability, with maximum measurement errors of 0.000067 RIU for RI, 0.0094 for pH, and 0.3°C for temperature. The sensor is simple to fabricate, low-cost, compact, and suitable for multi-parameter measurements in complex environments. This SPR sensor demonstrates broad applicability across multiple domains, including biosensing, environmental monitoring, and chemical analysis.

Lu2O3/h-BN Modified U-Shaped Fiber Optic SPR Sensor With Improved Sensitivity

Qi Wang,Hao-Yue Wang,Nuerguli Kari

Rapid and incredibly sensitive analyte detection is crucial in a variety of settings, including medical diagnostics. However, conventional surface plasmon resonance (SPR) sensors cannot effectively solve the issue of low sensitivity when assaying trace analytes. In this work, the rare Earth oxide Lu2O3 is first introduced to modify fiber optic SPR sensor. By utilizing the inherent advantages of Lu2O3, including high dielectric constant, high breakdown field strength, and high photoelectric conversion efficiency, the electric field around the sensor is effectively increased and high sensitivity detection is achieved. Experimental results show sensitivity of the sensor modified with Lu2O3 nanomaterial reaches 12133.78 nm/RIU in the interval of 1.3614–1.3756. The hexagonal boron nitride (h-BN) is subsequently introduced to further enhance electric field using the charge transfer mechanism. The sensitivity reaches 15065.92 nm/RIU, 3.96 times better than conventional U-shaped fiber SPR sensors. The sensor is compact designed with high sensitivity. There is significant potential for improving the sensitivity aspect of analyte detection.

Sensitivity-Enhanced Optical Fiber Biosensor Based on Coupling Effect Between SPR and LSPR

Bo-Tao Wang,Qi Wang

Dual-mode SPR/SERS optical fiber sensor for ultra-trace mercury ions detection

Lixia Li,Jiabin Zhao,Mingdeng Jin,Siyuan Wu,Feiyou Liu,Yurui Huang,Ning Feng,Yufang Liu,Yufang Liu

The detection of mercury ions (Hg2+) is crucial due to its harmful effects on health and environment. In this article, what we believe to be a novel dual-mode optical fiber sensor incorporating surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS) is proposed for ultra-trace Hg2+ detection. The sensing probe comprises gold (Au)/graphene oxide (GO) composite membrane structure and Au nanospheres (AuNPs), which are connected via double-stranded DNA. In the presence of Hg2+, two single-stranded DNA (ssDNA) modified on the sensing region and AuNPs asymmetrically pair to form a thymine (T) - Hg2+ - T structure, facilitating AuNPs attachment to the sensing region. This attachment induces spectral changes, thereby enabling Hg2+ detection. In the SPR mode, the limit of detection (LOD) for Hg2+ is 1.82 × 10−12 M. In the SERS mode, AuNPs generate numerous “hot spots” that amplify the Raman signal through electromagnetic enhancement mechanism (EM), the Au/GO composite membrane can undergo charge transfer with Raman molecule to further enhance the Raman signal through chemical enhancement mechanism (CM), thus achieving detection of Hg2+ with a LOD of 3.94 × 10−13 M. The synergy between SPR mode and SERS mode enhances cross-validation of results and improves accuracy and reliability of the assay. Therefore, the sensor proposed in this paper demonstrates strong potential for diverse practical applications.

Rapid and regenerable surface plasmon resonance determinations of biomarker concentration and biomolecular interaction based on tris-nitrilotriacetic acid chips

Luyao Liu,Chaowei Han,Meng Jiang,Tiantian Zhang,Qing Kang,Xiaoying Wang,Pengcheng Wang,Feimeng Zhou

The tris-nitrilotriacetic acid (tris-NTA) chip has been used for surface plasmon resonance (SPR) kinetic studies involving histidine (His)-tagged proteins. However, its full potential, especially for analyte quantification in complex biological media, has not been realized due to a lack of systematic studies on the factors governing ligand immobilization, surface regeneration, and data analysis. We demonstrate that the tris-NTA chip not only retains His-tagged proteins more strongly than its mono-NTA counterpart, but also orients them more uniformly than protein molecules coupled to carboxymethylated dextran films. We accurately and rapidly quantified immunoglobulin (IgG) molecules in sera by using the initial association phase of their conjugation with His-tagged protein G densely immobilized onto the tris-NTA chip, and established criteria for selecting the optimal time for constructing the calibration curve . The method is highly reproducible (less than 2% RSD) and three orders of magnitude more sensitive than immunoturbidimetry. In addition, we found that the amount of His-protein immobilized is highly dependent on the protein isoelectric point (pI). Reliable kinetic data in a multi-channel SPR instrument can also be rapidly obtained by using a low density of immobilized His-tagged protein. The experimental parameters and procedures outlined in this study help expand the range of SPR applications involving His-tagged proteins.

An MMF–HCF Reflective SPR Sensor for Simultaneous Measurement of Temperature and Relative Humidity

Chuanxin Teng,Yang Liu,Rui Min,Xuehao Hu,Zujun Qin,Hongchang Deng,Libo Yuan

In this article, a reflective surface plasmon resonance (SPR) sensor based on multimode fiber (MMF)–hollow core fiber (HCF) structure is proposed for simultaneous measurement of temperature and humidity. Along the HCF, two different films, i.e., polyvinyl alcohol (PVA) film and polydimethylsiloxane (PDMS) film are coated on the outer surface to generate two SPR resonances at different wavelengths and achieve the simultaneous measurement function. In order to get a better sensing performance, the length ratio of PVA film and PDMS film, and the PVA coating times are optimized. The experimental results show that the humidity sensitivity of the sensor is 0.6351 nm/% relative humidity (RH) in the RH range of 48%–84% RH, and the temperature sensitivity of the sensor is 1.791 nm/°C in the temperature measurement range of 25 °C–80 °C. The sensor has great potential applications in monitoring the environmental temperature and humidity changes.

A reflective optical fiber SPR sensor with surface modified hemoglobin for dissolved oxygen detection

Meiju Luo,Qi Wang

A new dissolved oxygen sensor based on optical fiber surface plasmon resonance (SPR) theory and the mechanism of oxygen transporting by hemoglobin was proposed and demonstrated. Gold film was coated on the surface of the optical fiber sensing area, and hemoglobin was modified on the surface of the gold film. The experimental results show that the sensor has good linearity and the limit of detection (LOD) of the sensor is 0.03 mg/L. In addition, in order to enhance the sensitivity of the sensor, the carbon nanotubes were modified on the surface of the gold film of the fiber, and then the hemoglobin was modified in the outermost layer. Through experiments, it was found that the sensitivity of the sensor which modified with carbon nanotubes is 2.8-folds higher than that only modified hemoglobin, the linearity is better, and the LOD is reduced to 0.01 mg/L.

Biotin-streptavidin sandwich integrated PDA-ZnO@Au nanocomposite based SPR sensor for hIgG detection

Haohua Yang,Xueqi Zhao,Ziwei Zhang,Pinyi Ma,Xinghua Wang,Daqian Song,Ying Sun

SPR is a mature optical biosensor technology for detecting biomolecular interactions without fluorescence or enzyme labeling. In this paper, we acquire a sensitive SPR biosensor based on [email protected] nanomaterial , and the classical sandwich strategy using biotin-streptavidin for secondary signal amplification system was used to detect human IgG (hIgG). Nano-zinc oxide (ZnO) has the dual characteristics of nanocomposite and traditional zinc oxide, with large specific surface area and high chemical activity. Besides, the gold-coated ZnO nanocrystals improve the optical properties of ZnO and enlarge the loading capacity with better biocompatibility. Therefore, a sensing platform based on [email protected] nanomaterial was constructed on gold film modified with mercaptan. Meanwhile, the biotin-avidin system in SPR sensor field has been rapidly developed and applied. Due to the highly selection of streptavidin (SA) and biotin interact with each other, GNRs-SA-biotin-Ab 2 (GSAB-Ab 2 ) were constructed to obtain the secondary enhancement of SPR signal. The influences of experimental conditions were also discussed. With optimal experimental conditions, introducing GSAB-Ab 2 conjugate combined with a sandwich format, the resulting SPR biosensor provides a favourable range for hIgG determination of 0.0375–40 μg mL −1 . The minimum detection concentration of hIgG that can be obtained by this method is approximately 67-fold lower than the conventional SPR sensor based on gold film. The sensitivity of SPR biosensor is significantly improved in a certain range.

High-sensitivity optical fiber SPR temperature sensing probe based on Au-PDMS@Au coating

Ting Liu,Zhipeng Lin,Changfei Lai,Wei Guo,Shouyu Wang

To enhance the sensitivity of polydimethylsiloxane (PDMS)-based optical fiber surface plasmon resonance (SPR) temperature sensing probes, we propose a new prototype with a PDMS@Au sensing layer on the gold (Au) film of the multi-mode fiber (MMF)-single-mode fiber (SMF)-MMF heterojunction structure. This designed probe has improved the temperature sensitivity from −1.26 nm/°C (Au-PDMS) to −2.14 nm/°C (Au-PDMS@Au), maintaining good repeatability and stability. Moreover, the probe can be fabricated with simple procedures at a low cost. Therefore, this probe is a promising tool for temperature sensing in various applications.

SPR-promoted Bi/Bi2WO6 heterojunction with effectively enhanced visible light photocatalytic degradation of pollutants

Shukang Jiang,Guangwei Zheng,Junhao Sun,Fengqing Zhang,Hongwen Yu

The surface plasmon resonance (SPR) of plasmonic metals is an effective strategy for enhancing photocatalytic efficiency. Herein, we successfully synthesized the SPR-promoted Bi/Bi 2 WO 6 heterojunction photocatalysts by in situ reduction of Bi 3 + in Bi 2 WO 6 nanosheets to plasmonic Bi via a facile solvothermal method. The size of Bi nanoparticles on the surface of Bi 2 WO 6 was adjusted by varying the solvothermal temperature. After 15 min of visible light irradiation, the Bi/Bi 2 WO 6 heterojunction with a suitable size of metal Bi obtained after solvothermal treatment at 160°C exhibited 100 % degradation of Rhodamine B (RhB), which was 2.3 times greater than that of the pure Bi 2 WO 6 . The excellent photodegradation performance of this sample can be attributed to the SPR effect of metal Bi, which enhances light absorption, generates active sites and species, and facilitates rapid carrier transfer. Additionally, the formation of the Bi/Bi 2 WO 6 Schottky heterojunction promotes carrier separation and minimizes the recombination of photogenerated electron-hole pairs. Furthermore, a potential mechanism for the photodegradation process of the synthesized photocatalyst has been proposed. This work not only offers new perspectives on in situ fine-tuning strategies for Bi-based photocatalysts but also demonstrates the potential of low-cost metallic Bi as a viable alternative to noble metals for enhancing photocatalytic performance.