查找使用阿拉丁产品的科研文献

Ultra-Wide-Range SPR Fiber-Optic Sensing System for Multiparameter Detection in Complex Aqueous Environments

Pengxiao Guo,Huijing Du,Jianshe Li,Lei Zhang,Shuguang Li

To address the strong coupling, large-gradient variations, and temperature cross-sensitivity among multiple physicochemical parameters such as refractive index (RI), pH, and temperature in complex aqueous environments, an ultra-wide-range surface plasmon resonance (SPR) fiber-optic sensing platform is proposed. By constructing three independent sensing regions (Ag, Ag/TiO₂, and Ag/MoS₂), multi-channel spectral gradient partitioning and direct signal mapping are realized, thereby avoiding signal overlap and reducing demodulation complexity. Specifically, the natural hydroxyl binding sites on the TiO₂ surface are utilized to load the PAA/CS polyelectrolyte sensitive membrane to construct a pH-responsive interface; MoS₂ combined with PDMS is used to achieve temperature sensitivity; and the Ag interface is used for RI detection. In addition, the matrix demodulation method is adopted to compensate for temperature-induced cross-sensitivity in the RI and pH channels. The experimental results demonstrate that this sensor can simultaneously detect RI (1.333-1.403), pH (3.22-13.21), and temperature (-20-100 °C), and maintain high accuracy and sensitivity within a wide dynamic range. This research can effectively address the issue of the coordinated changes in RI, pH, and temperature, providing an effective optical fiber sensing solution for the high-precision monitoring of multi-parameter coordinated changes in complex aqueous environments.

High-sensitivity SPR refractive index sensor based on a PbF2-coated U-shaped optical fiber

Qi-Zhi Cai,Jia-Qi Wang,Ben Li,Na-Na Du,Hua-Long Du,He-Yun Zhang,Jia-Jun Diao,Qi Wang

A PbF 2 -assisted dielectric modulation strategy was proposed for enhancing SPR response in U-shaped fiber sensors. • The PbF 2 layer achieved a 1.97-fold enhancement in local electric-field intensity through interfacial dielectric modulation. • The experimentally fabricated coating showed excellent agreement with the optimized 70 nm design predicted by FEM simulations. • The proposed sensor achieved an average RI sensitivity of 8483.58 nm/RIU over 1.3381–1.3778. • A maximum sensitivity of 14195.32 nm/RIU and an experimental FOM of 40.42 RIU −1 were obtained. To improve the sensitivity of fiber-optic SPR sensors, a lead fluoride (PbF 2 ) sensitizing layer was introduced into a U-shaped fiber SPR configuration as a fluoride-based dielectric modulation layer. The proposed sensor was designed using a U-bent multimode fiber integrated with a PbF 2 -modified layer and was evaluated by FEM simulation and experimental testing. In the FEM simulation, the local electric field near the sensing interface became stronger after adding the PbF 2 -containing layer, with a peak intensity about 1.97 times higher than that of the pure-Au structure. The stronger electric field is mainly associated with the change in the effective dielectric environment and the redistribution of the evanescent field at the Au/analyte interface after introducing the PbF 2 -containing layer. The wide band gap and optical transparency of PbF 2 also make it suitable as a low-loss dielectric sensitizing layer. In the simulation, a PbF 2 thickness of 70 nm gave the best overall response. Experimentally, the sensor showed an average RI sensitivity of 8483.58 nm/RIU over the RI range of 1.3381–1.3778. For comparison, the pure-Au U-shaped sensor had a sensitivity of 4207.54 nm/RIU, corresponding to a 2.02-fold improvement after PbF 2 modification. In the high-RI range of 1.3669–1.3778, the sensitivity reached 14,195.32 nm/RIU, which was 3.37 times higher than that of the pure-Au sensor. The sensor also showed good stability under the tested conditions, with a thermal drift coefficient of 0.4867 nm/°C from 30 °C to 60 °C and an average sensitivity RSD of 0.6181% in repeated RI measurements. The PbF 2 -containing layer therefore improves the RI response of the U-shaped fiber SPR sensor through interfacial dielectric modulation.

High-sensitivity and high-specificity optical fiber SPR doxorubicin sensor enabled by Ti3C2 MXene sensitization

Like Li,Yi Li,Guohong Zou,Lu Cai,Maoqing Chen,Xiaoming Chen,Bo Han,Ya-nan Zhang,Yong Zhao

Doxorubicin, as an anthracycline antibiotic, is a commonly used and effective chemotherapeutic agent for treating various malignancies. However, it has a narrow therapeutic window. Therefore, real-time monitoring of doxorubicin concentration in chemotherapy patients is essential for enhancing treatment efficacy, minimizing side effects, and ensuring patient safety. In this paper, we proposed a Ti 3 C 2 MXene-sensitized fiber surface plasmon resonance (SPR) doxorubicin sensor. By covalently functionalizing the reflective SPR sensing structure with Ti 3 C 2 MXene, the refractive index sensitivity increased by 60.0 %. Furthermore, by covalently modifying the doxorubicin-specific aptamer, the sensor achieves high sensitivity and high specificity in the detection of doxorubicin. Within the linear range of 10–100 μM, it demonstrates a sensitivity of 0.24 nm/μM and a limit of detection of 2.79 μM. Furthermore, experiments confirmed that the doxorubicin sensor exhibits excellent specificity and can be applied for the detection of doxorubicin in real serum samples. The proposed doxorubicin sensor offers benefits such as high sensitivity, high specificity, fast response, and small size, and has the potential to meet the clinical requirements for monitoring doxorubicin concentration in chemotherapy patients.

Fiber-Based SPR Sensor for Ultrahigh-Sensitivity Creatinine Sensing Based on Enzymatic Self-Assembly Structure

Pengqi Gong,Xuegang Li,Xue Zhou,Fang Wang,Yanan Zhang,Yong Zhao

In this article, we presented an ultrahigh-sensitivity creatinine (CRE) sensor based on the optical fiber surface plasmon resonance (SPR) effect and layer-by-layer self-assembly technology. The self-assembly technology is used to immobilize different polymer films containing creatininase (CA) molecules on the sensor surface. We found and verified that CRE decomposition products can induce the expansion effect of multilayer self-assembled polymer films and further cause the rapid reduction of the refractive index (RI) of polymer films. The SPR effect can detect this RI change and therefore infer the presence and concentration of CRE. The CRE detection results of SPR sensors with and without the self-assembly structure confirmed that the CRE sensitivity of SPR sensors improved by 11.6-fold and the limit of detection (LOD) reached $10^{-5}$ mg/mL when the SPR sensor combined with the self-assembly structure. Moreover, the selective recognition ability of the SPR sensor with the self-assembly structure has been confirmed by comparing the detection results of CRE and non-CRE samples. In addition, the underlying principle of the sensitization technique using self-assembled polymer films and specific biorecognition molecules (like CRE in this case) has the potential to be adapted for the detection of various other biomolecules, which could provide a new way for the development of highly sensitive and specific biosensors.

Sensitive determination of arginine based on hydrogen bonding by a surface plasmon resonance (SPR) sensor

X.-C. Fan,Q. Wang

A highly sensitive arginine sensor based on optical fiber surface plasmon resonance (SPR) and 11-mercaptoundecanoic acid (MUA) was studied and implemented in this work. The method of modifying the mercaptoundecanoic acid molecule on the surface of the sensing area was proposed initially by using molecular self-assembly technology in order to complete the detection of arginine. The detection principle is a hydrogen bond-based aggregation between mercaptoundecanoic acid and arginine. The close alignment of the mercaptoundecanoic acid molecules allows the aggregation of arginine to affect changes within the surrounding local refractive index. This aggregation was selective for the arginine molecules. The sensor probe has a detection limit of 0.005 μM and a sensitivity of up to 1474 nm/μM. The entire detection system, including the probe, has the advantages of being low cost, small in size, easy to operate, and uses low power. This approach has the potential to be developed as a mobile and fast-detection method.

Reproducible Quantification of Pseudomonas aeruginosa via MIP-Functionalized SPR-FPI Optical Fiber Sensor

Wanlu Zheng,Weixin Kong,Na Zhang,Zhong Li,Ya-nan Zhang

reusable optical fiber surface plasmon resonance (SPR) sensor for quantitative detection of Pseudomonas aeruginosa is presented. To achieve repeatable measurement, this study used aptamer DNA as the functional monomer and polydopamine as the cross-linking agent to construct a molecularly imprinted nanofilm on the sensing surface. After elution treatment, molecularly imprinted cavities with high matching shape and size to the target molecule are formed in the nanofilm. Experimental results demonstrated that the sensors enhanced by molecular imprinting technology achieved an increase in resonance wavelength response from 10.677 nm to 24.98 nm, a reduction in response time from 22 minutes to 16 minutes, and an improvement in detection limit from 0.00985 OD to 0.00105 OD, compared with sensors only modified with functional monomers. Moreover, to address the problem of temperature interference in practical applications, a Fabry-Perot interferometer (FPI) is innovatively integrated. By taking advantage of the temperature sensitivity but bacterial insensitivity of FPI, the influence of temperature changes on SPR measurement is quantified, effectively providing temperature compensation and further improving the environmental adaptability of the sensor. This study provides a novel, reliable, and cost-effective detection solution for marine environmental microbial monitoring.

Fiber-Optic SPR pH Sensor Based on MMF–NCF–MMF Structure and Self-Assembled Nanofilm

Like Li,Ya-Nan Zhang

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

Yingzi Xiong,Yanan Cao,Maiquan Li,Ruozhong Wang,Langtao Xiao,Xia Liu

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 enhanced SPR immunosensor based on graphene oxide and SPA co-modified photonic crystal fiber

Qi Wang,Botao Wang

A sensitivity enhanced surface plasmon resonance (SPR) immunosensor based on Graphene oxide (GO) composite and staphylococcal protein A (SPA) co-modified photonic crystal fiber (PCF) is developed for human IgG detection. The PCF spliced between two section of multimode fibers (MMFs) is sputtered with gold film, which was then modified with graphene oxide and SPA for further immunosensing. Graphene oxide with abundant functional groups has a large surface area for more biomolecules immobilization and can enhance the interaction between Au film and external medium, leading to the sensitivity increased greatly. SPA can specifically bind the Fc region of the antibodies and has a high degree of orientation for capturing antibodies. Experimental results indicated that the refractive index (RI) sensitivity of graphene oxide modified Au-PCF SPR sensor reaches 4649.8 nm/RIU, which is about 1888 nm/RIU higher than that without graphene oxide film and the human IgG detection limit reaches as low as 10 ng/mL. Such a sensitivity enhanced immunosensor based on graphene oxide and SPA co-modified PCF shows a great promise in biosensing.

The Ag-based SPR effect drives effective degradation of organic pollutants by BiOCOOH/AgBr composites

Cong Lu,Haifeng Zhou

The easy recombination of electron-hole pairs produced by monomeric photocatalysts under light exposure severely limits their application in wastewater treatment. Based on this, BiOCOOH/Ag/AgBr ternary photocatalysts in flower-like microspheres were controllably synthesized by precipitation photoreduction and characterized by various techniques. In addition, the effects of different molar ratio of BiOCOOH and AgBr, catalyst dose, pH and coexisting ions on the photocatalytic degradation of rhodamine B (RhB) and tetracycline (TC) were investigated. The results showed that the BOC/Ag/AgBr-0.5 composite exhibited excellent photocatalytic activity for the degradation of RhB and TC. The excellent photocatalytic activity was mainly attributed to the surface plasmon resonance (SPR) effect of metallic Ag and charge transfer mechanism between composites, thus promoting charge separation. The degradation efficiency of RhB and TC was 92.7% and 72.3% with the degradation rate constant of 0.073 and 0.023 under light irradiation of xenon lamp in 30 and 45 min, respectively, which was 6 and 2 times higher than that of BiOCOOH and AgBr. The stability studies showed that BOC/Ag/AgBr-0.5 maintained a high catalytic activity after four cycles. The results of radical capture experiments showed that h + and · O 2 – were the main reactive radicals, while · OH played a secondary role in the photocatalytic system. Subsequently, a potential photocatalytic mechanism was proposed based on the experimental results.

Ion-imprinted-polymer coated fiber-optic SPR sensor for detection of trace Cr3+ in water

Wenlin Feng,Chenyuan Yuan,Ting Li,Xiaozhan Yang

A fiber-optic surface plasmon resonance (SPR) sensor based on the trivalent chromium-ion imprinted polymer (Cr 3+ -IIP) was proposed and fabricated. A small core-diameter fiber (SCF) with a length of 1 cm is spliced between two multimode fibers (MMFs) to form the MMF-SCF-MMF sensing structure. A 67-nm thick Ag film was evaporated on the outside surface of the SCF, and then Cr 3+ -IIP and nonionic imprinted polymer materials were respectively coated on the surface of the Ag film and then the fiber-optic SPR sensor was obtained. The results show that with the increase of Cr 3+ concentration in the range of 0–1.1 µM, the SPR peak indicates redshift with 80.5 nm. The sensitivity and linearity of the sensor are 71.7 nm/µM and 0.994, respectively. The limit of detection of the sensor is about 0.041 μM (2.145 ppb). The fiber-optic SPR sensor is expected to be applied to the detection of trace Cr 3+ ions in water.

A Dual-Parameter Optical Fiber SPR Sensor for Simultaneous Measurement of Glucose and Cholesterol Concentrations

Xingyu Wang,Xiaoyan Sun,Youwang Hu,Limu Zhang,Li Zeng,Qishi Liu,Ji’an Duan