查找使用阿拉丁产品的科研文献

SPR sensor based on sapphire prism coupling with dual-Au-layer sandwiched GaN structure for enhanced sensitivity and FOM

Zhuo-Yu Jin,Chu Cao,Nuerguli Kari,Dian-Yun Zhang,Qi Wang

Surface plasmon resonance (SPR) sensors are currently applied in various fields, driving the development of precise detection technologies. However, few designs effectively balance ease of fabrication, high detection performance, and structural stability. To address this challenge, we developed an SPR sensor with a sapphire prism-Au/Gallium Nitride (GaN)/Au composite film structure. The GaN thin film enhances sensitivity, while the coupling between the dual Au layers and sapphire reduces the full width at half maximum (FWHM) and improves sensor stability. Simulation results indicate a significant increase in the electric field intensity at the sensor surface. Experimental results demonstrate that the structure exhibits excellent long-term stability. Compared with conventional Au film sapphire prism SPR sensors, this design achieves a 3.14-fold increase in sensitivity and a 5.43-fold improvement in the figure of merit (FOM). This study presents a novel approach to further enhancing SPR sensor performance and highlights the potential applications of this structure in detection technologies.

Theoretical and experimental study of a highly sensitive SPR biosensor based on Au grating and Au film coupling structure

Haoyuan Cai,Haoyuan Cai,Haoyuan Cai,Haoyuan Cai,Mengwei Wang,Mengwei Wang,Mengwei Wang,Jing Liu,Jing Liu,Xiaoping Wang,Xiaoping Wang,Xiaoping Wang,Xiaoping Wang

A high-sensitivity surface plasmon resonance (SPR) sensor based on the coupling of Au grating and Au film is investigated through simulations and experiments. The SPR sensor is designed by using a hybrid method composed of genetic algorithm (GA) and rigorous coupled wave analysis (RCWA). The numerical results indicate the sensor has an angular sensitivity of 397.3°/RIU (refractive index unit), which is approximately 2.81 times higher than the conventional Au-based sensor and it is verified by experiments. Theoretical analysis, by finite-difference time-domain (FDTD) method, demonstrates the co-coupling between surface plasmon polaritons (SPPs) propagating on the surface of Au film and localized surface plasmons (LSPs) in the Au grating nanostructure, improving the sensitivity of the SPR sensor. According to the optimized structural parameters, the proposed sensor is fabricated using e-beam lithography and magnetron sputtering. In addition, the proposed sensor is very sensitive to the detection of small molecules. The limit of detection (LOD) for okadaic acid (OA) is 0.72 ng/mL based on an indirect competitive inhibition method, which is approximately 38 times lower than the conventional Au sensor. Such a high-sensitivity SPR biosensor has potential in the applications of immunoassays and clinical diagnosis.

Preparation of Ag SPR-promoted TiO2-{001}/HTiOF3 photocatalyst with oxygen vacancies for highly efficient degradation of tetracycline hydrochloride

Chentao Hou,Huayang Liu,Mohammad Fahim Bakhtari

In order to solve the problem of tetracycline hydrochloride (TCH) wastewater pollution, a photocatalyst for the efficient utilization of sunlight was proposed. In this work, a new method for the synthesis of three-dimensional flower-like Ag/TiO 2 -{001}/HTiOF 3 photocatalyst was applied, where surface oxygen vacancies can induce Ag nanoparticles (NPs) to disperse on the surface of the photocatalyst, which avoids the aggregation of Ag NPs into large particles. The appropriate mesoporous structure of the photocatalyst makes TCH have a stronger affinity on its surface, which is more conducive to the subsequent photodegradation . Furthermore, the surface plasmon resonance (SPR) of Ag NPs extends the response region of photocatalyst to visible light, and the heterojunction formed with TiO 2 /HTiOF 3 further stimulates the electrons in the oxygen vacancy region and inhibits the recombination of carriers. 10-Ag/TiO 2 /HTiOF 3 showed the best degradation activity (96%) for TCH when the ratio of Ag and TiO 2 -{001}/HTiOF 3 was 10%. In addition, the Ag/TiO 2 -{001}/HTiOF 3 photocatalyst has excellent photocatalytic activity , structural stability and sedimentation performance. The prepared catalyst has practical application prospect.

11-MUA/Ag Modified Large-Core Fiber-Optic SPR Sensing Probe and Its Highly Sensitive Detection for Rabies Virus

Juan He,Qian Liao,Wenlin Feng

High-performance and fast fiber-optic SPR gas sensor based on WO3/SnO2 nanocomposites films for room-temperature NH3 detection

Chong Li,Yan Wang,Jinqiao Hou,Huanming Wang,Jingting Luo,Chen Fu,Fujian Ren,Jikai Zhang,Huiling Ong,Chenze Lu,Hang Xiao,Xi Chen,Ran Tao,Yuzhi Chen,Yongqing Fu,Qiang Wu,Xuejin Li

Ammonia, a key biomarker existing in human breath, plays a critical role in non-invasive breath testing at room temperature. Among various ammonia sensors, reflective fiber-optic sensors based on surface plasmon resonance (SPR) offer significant advantages, including high sensitivity, small footprint, and portability, making them ideal for room-temperature gas sensing. In this work, WO 3 /SnO 2 nanocomposites were synthesized via a solvothermal method to obtain sensitive materials for room-temperature NH 3 detection. The WO 3 /SnO 2 nanocomposites were deposited on the surface of the SPR fiber by dip-coating to form a uniform gas-sensitive film. The sensor exhibited exceptional performance, achieving a high sensitivity of −10.84 a.u./ppm, a fast response time of 2 s, and a theoretical limit of detection of 277 ppb at room-temperature. The enhanced sensing mechanism is attributed to the formation of WO₃-SnO₂ heterojunctions, which facilitate efficient charge transfer and amplify SPR signals via dielectric modulation. This work highlights the potential of low-dimensional material-integrated optical fiber platforms for non-invasive medical diagnostics through breath ammonia detection.

The heterojunction regulated by Au nanoparticles efficient removal of NO through the synergistic effects of SPR and the electron bridge

Youzhou He,Zhiqiang Guo,Yue Li,Xingyan Liu,Kaili Wu,Yuyu Fang,Rong Peng,Min Fu,Bowen Lei

The elimination of low-concentration (ppb) nitrogen oxides (NO x ) in city and indoor environments, particularly the selective removal of NO while preventing toxic NO 2 formation is a significant challenge. Photocatalytic technology offers a promising solution, but its effectiveness is limited by high carrier recombination rates and insufficient active sites. This study introduces a photocatalyst (Au@NM/ZIF) that forms a Z-type heterojunction structure by precisely positioning gold nanoparticles within the NM/ZIF framework. The catalyst consists of amino-functionalized NH 2 -MIL-125 and ZIF-8, with gold nanoparticles serving dual roles: UV-Vis analysis shows that their surface plasmon resonance (SPR) enhances visible light absorption, promoting the generation of charge carriers that drive the oxidation of NO to NO 3 − . Additionally, X-ray photoelectron spectroscopy (XPS) and work function analysis indicate that gold nanoparticles function as an electronic bridge, optimizing charge transfer between NM and ZIF-8, improving electron-hole separation and increasing active site utilization, thereby significantly enhancing NO conversion efficiency. In situ Fourier-transform infrared spectroscopy (FT-IR), electron spin resonance (ESR), and radical capture experiments further clarify the formation pathways of preliminary products and completed outputs, emphasizing the important roles of active radicals (such as •OH and •O 2 − ) in the deep oxidation of NO. This research offers a valuable solution for effectively removing low-concentration NO x .

A PDA/AuNPs/PDANPs sandwich structure modified fiber optic SPR biosensor for high precision and specific detection of Rabbit IgG

Tengfei Yang,Pengxiang Chang,Ailing Zhang,Fei Liu,Honggang Pan,Junfeng Wang,Guangxiao Cao,Mingxuan Zheng,Zhao Zhang

A PDA/AuNPs/PDANPs sandwich structure modified optical fiber surface plasmon resonance (SPR) biosensor for specific detecting of rabbit IgG were proposed in this paper. On the proposed sensor, polydopamine (PDA), gold nanoparticles (AuNPs) and polydopamine nanoparticles (PDANPs) were sequentially deposited to form a multilayer hybrid structure. The refractive index (RI) sensitivity of the sensor has been significantly enhanced through the strong coupling effects of SPR and localized surface plasmon resonance. The sensor achieves an RI sensitivity of3009.58 nm/RIU, representing a 3-fold increase compared to the original SPR sensor. In addition, due to the high surface activity and large specific surface area of PDANPs, the biosensitivity of the sensor has been enhanced. The sensor demonstrated specific detection of Rabbit IgG with a biosensitivity of 0.9157 nm/(μg/mL) and limit of detection (LOD) of 22 ng/mL. These findings indicate that the prepared sensor can specifically detect Rabbit IgG with high precision and a low LOD. Therefore, this PDA/AuNPs/PDANPs sandwich structure modified biosensor has great potential in clinical detection and other bio-detection fields.

Surface plasmon resonance (EC-SPR) sensor based on molecularly imprinted strategy for the determination of stimulant modafinil in saliva samples

Hui Yang,Xiaoqin Xu,Bichao Shu

A highly sensitive and selective molecularly imprinted polymer-based electrochemical-surface plasmon resonance (MIP-based EC-SPR) sensor was developed for the determination of modafinil in saliva samples. The optimal MIPpy film was synthesized using a modafinil concentration of 1 mM and a constant potential electropolymerization method. The fabricated sensor exhibited a wide linear range (0.1 μM to 10 μM), low detection limits (LOD: 50 nM, LOQ: 170 nM), and high selectivity towards modafinil, with selectivity coefficients of 8.5, 6.2, and 12.7 for adrafinil, armodafinil, and caffeine, respectively. The sensor also demonstrated excellent reproducibility (RSD: 4.2 %) and long-term stability (92 % response after one month). Furthermore, the applicability of the sensor in real samples was validated using spiked saliva samples, with recovery values ranging from 94.7 % to 103.5 %. These results highlight the potential of the MIP-based EC-SPR sensor as a powerful tool for the rapid, sensitive, and selective detection of modafinil in complex biological matrices.

Rapid and cost-effective screening of therapeutic targets for isoquercitrin in insulin resistance using virtual methods and fiber SPR biosensing

Yong Wei,Yuye Xuan,Wenxiang Wang,Yonghui Zhang,Xiaoshan Li,Chunlan Liu,Chen Wang,Zhihai Liu

The existing screening methods for therapeutic targets of active ingredients in traditional Chinese medicine (TCM) have problems of long detection time and high instrument cost. This article proposes a new target screening method based on virtual screening and fiber surface plasmon resonance (SPR) sensing technology, which has the characteristics of flexibility, speed, and low cost. It also reveals the target mechanism of the active ingredient isoquercitrin in the treatment of insulin resistance (IR). The binding energies of isoquercitrin with target proteins PDPK1, INSR, and PTPN1 were calculated using computer virtual methods to be -8.9, -8.9, -8.8 kcal/mol, indicating strong binding activity with isoquercitrin and predicted as three key targets. Then a fiber optic SPR biosensor functionalized with isoquercitrin molecules was constructed to detect the binding affinity between isoquercitrin and the key targets. The experimental results showed that the binding affinities of isoquercitrin to the targets PDPK1, INSR, and PTPN1 were 1.45, 1.14, and 13.21, respectively, indicating that PTPN1 is the main target of isoquercitrin in the treatment of IR. The proposed sensor has a sensitivity of 0.699 nm/(μg/ml), LOD of 0.515μg/ml, and the experimental detection time of this method is as low as 45 minutes, without the need for large and expensive optical demodulation equipment, and the device volume is 5.50 dm3, providing new ideas for the screening of therapeutic targets of active ingredients in TCM.

Dual-mode electrochemical fiber optic surface plasmon resonance sensor (EC-FO-SPR) for real-time and sensitive detection of lipopolysaccharide

Yue Wang,Siyu Qian,Duo Zhao,Shiyu Jiang,Xin Wang,Junao Zhang,Shudong Zhao,Yang Gao,Shengchun Liu

Lipopolysaccharide (LPS), a key component of the outer membrane of Gram-negative bacteria, is the primary trigger of septic shock. The rapid and selective detection of LPS is essential for effective disease prevention and treatment. The conventional prism-based electrochemical surface plasmon resonance (EC-SPR) system is limited by their bulky optical configurations, making it difficult to integrate into portable devices. In this study, we present a compact and implantable electrochemical fiber optic surface plasmon resonance (EC-FO-SPR) sensor to detect LPS. The gold-coated optical fiber serves a dual function as both SPR optical probe and working microelectrode, enabling simultaneous acquisition of optical and electrochemical signals. The sensor ensures high sensitivity by electrochemical detection mode and real-time monitoring molecular adsorption processes by optical SPR mode. The fiber sensing surface is modified with boric acid molecules for highly specific detection of saccharides with cis -diol structures such as glucose and the biomacromolecule LPS, which contains glucose units. The electrochemical signal is collected by detecting changes in the charge distribution of [Fe(CN) 6 ] 4- / 3- near the electrode surface caused by boronate ester formation, and the optical signal is obtained through refractive index changes near the electrode induced by target molecules. The sensor shows a clear linear relationship between LPS concentration and both SPR wavelength shift and electrochemical peak current. The fiber-based design of EC-FO-SPR is easily integrable into compact, flexible platforms, enabling real-time, in situ monitoring of molecular interactions. It provides a reliable and versatile support for clinical and biomedical applications.

A Temperature Self-Compensated Dual-Channel SPR Fiber Sensor With Ion-Imprinted Polymers for Simultaneous Detection of Cu²⁺ and Ni²⁺

Zhiyong Yin

The simultaneous and specific detection of multiple heavy metal ions in complex environments remains a significant challenge for optical fiber sensors, primarily due to spectral crosstalk and temperature interference. To address this, we present a monolithically-integrated, dual-channel surface plasmon resonance (SPR) fiber sensor capable of crosstalk-compensated and temperature-compensated detection of Cu²⁺ and Ni²⁺. The sensor is fabricated by cascading two sensing regions on a single microstructured optical fiber (MOF), where a strategic combination of heterogeneous metallic films—a silver film for the Cu²⁺ channel and a gold film for the Ni²⁺ channel—creates two spectrally distinct resonance dips in the visible range. To overcome the limitation of specificity, ion-imprinted polymers (polyacrylic acid and chitosan) are functionalized onto the respective channels, creating highly selective recognition sites. Furthermore, an independent temperature-sensing probe, with its resonance strategically located in the near-infrared region, is incorporated into the optical path for real-time temperature monitoring, effectively eliminating thermal cross-sensitivity. Experimental results demonstrate that the sensor exhibits high sensitivity (up to 0.41 nm/μM for Cu²⁺ and 0.34 nm/μM for Ni²⁺ in the low concentration regime), a fast response time (20-30 s), and low detection limits. This work provides a compact and robust all-in-one sensing solution that paves the way for practical, multi-analyte environmental monitoring.

A Point-of-Care Testing Device Utilizing Graphene-Enhanced Fiber Optic SPR Sensor for Real-Time Detection of Infectious Pathogens

Shiyu Jiang,Siyu Qian,Shunning Zhu,Jinxin Lu,Yunxin Hu,Cheng Zhang,Yikai Geng,Xuefeng Chen,Ying Guo,Zhaoliang Chen,Jie Pu,Zhendong Guo,Shengchun Liu

Timely detection of highly infectious pathogens is essential for preventing and controlling public health risks. However, most traditional testing instruments require multiple tedious steps and ultimately testing in hospitals and third-party laboratories. The sample transfer process significantly prolongs the time to obtain test results. To tackle this aspect, a portable fiber optic surface plasmon resonance (FO-SPR) device was developed for the real-time detection of infectious pathogens. The portable device innovatively integrated a compact FO-SPR sensing component, a signal acquisition and processing system, and an embedded power supply unit. A gold-plated fiber is used as the FO-SPR sensing probe. Compared with traditional SPR sensing systems, the device is smaller size, lighter weight, and higher convenience. To enhance the detection capacity of pathogens, a monolayer graphene was coated on the sensing region of the FO-SPR sensing probe. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was used to evaluate the performance of the portable device. The device can accurately detect the SARS-CoV-2 spike S1 protein in phosphate-buffered saline (PBS) and artificial saliva within just 20 min, and the device successfully detected cultured SARS-CoV-2 virus. Furthermore, the FO-SPR probe has long-term stability, remaining stable for up to 8 days. It could distinguish between the SARS-CoV-2 spike protein and the MERS-CoV spike protein. Hence, this FO-SPR device provides reliable, rapid, and portable access to test results. It provides a promising point-of-care testing (POCT) tool for on-site screening of infectious pathogens.Keywords:surface plasmon resonance;infectious pathogen detection;portable device;graphene film;point-of-care testing