An optical fiber surface plasmon resonance (SPR) sensor, leveraging hyperbolic metamaterials (HMMs) and pH-sensitive hydrogels, has been devised for pH detection in perspiration. Dispersion-tunable HMMs enable the sensor to transcend the inherent structural constraints of an optical fiber and enhance its refractive index (RI) sensitivity. pH-sensitive hydrogels exhibit diverse swelling behaviors due to varying ionization degrees of carboxyl groups under different solution pH conditions, leading to a notable RI change.
View Article and Find Full Text PDFSurface 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.
View Article and Find Full Text PDFElectrophysiological (EP) signals are key biomarkers for monitoring mental fatigue (MF) and general health, but state-of-the-art wearable EP-based MF monitoring systems are bulky and require user-specific, labeled data. Ultrathin epidermal electrodes with high performance are ideal for constructing imperceptive EP sensing systems; however, the lack of a simple and scalable fabrication delays their application in MF recognition. Here, we report a facile, scalable printing-welding-transferring strategy (PWT) for printing μm-thickness micropatterned silver nanowires (AgNWs)/sticky polydimethylsiloxane, welding the AgNWs via plasmonic effect, and transferring the electrode to skin as tattoos.
View Article and Find Full Text PDFThe longitudinal relaxation time (termed as T) of nitrogen-vacancy (NV) centers in nanodiamonds can be affected by surface electric or magnetic noise, which has been exploited to develop cutting-edge quantum relaxometry for biochemical sensing. In this work, a tiny all-fiber quantum probe based on longitudinal relaxometry was developed by chemically-anchoring nanodiamonds on the surface of a cone fiber tip. The dependences of T on surface electric and magnetic noise were discussed in theories first and then experimentally demonstrated in varied pH and Gd concentration solutions, respectively.
View Article and Find Full Text PDFIn recent years, utilizing nitrogen-vacancy color centers in diamond for temperature sensing has drawn great attention. However, increasing the sensitivity has encountered challenges due to the intrinsic temperature-dependent energy level shift, i.e.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2024
Silver nanowire (AgNW) networks with self-assembled structures and synaptic connectivity have been recently reported for constructing neuromorphic memristors. However, resistive switching at the cross-point junctions of the network is unstable due to locally enhanced Joule heating and the Gibbs-Thomson effect, which poses an obstacle to the integration of threshold switching and memory function in the same AgNW memristor. Here, fragmented AgNW networks combined with Ag nanoparticles (AgNPs) and mercapto self-assembled monolayers (SAMs) are devised to construct memristors with stable threshold switching and memory behavior.
View Article and Find Full Text PDFBiosensors (Basel)
April 2023
Surface plasmon resonance (SPR) based sensors play an important role in the biological and medical fields, and improving the sensitivity is a goal that has always been pursued. In this paper, a sensitivity enhancement scheme jointly employing MoS nanoflower (MNF) and nanodiamond (ND) to co-engineer the plasmonic surface was proposed and demonstrated. The scheme could be easily implemented via physically depositing MNF and ND overlayers on the gold surface of an SPR chip, and the overlayer could be flexibly adjusted by controlling the deposition times, thus approaching the optimal performance.
View Article and Find Full Text PDFMagnetic field detection exploiting nitrogen-vacancy (NV) centers in diamond has gained increasing attention and development in recent years. Combining diamond NV centers to optical fibers provides a way for achieving magnetic sensors with high integration and portability. Meanwhile, new methods or techniques are urgently desired to improve the detection sensitivity of such sensors.
View Article and Find Full Text PDFExosomes isolated from platelet-rich plasma (PRP-exos) have been recently deemed as an optimized therapeutic strategy in diabetic foot ulcer (DFU) treatment. Herein, we aimed to explore whether MALAT1 participates in DFU wound healing by PRP-exos treatment and the related preliminary mechanism. Fibroblasts were isolated from healthy donors and DFU patients, and the expression of MALAT1, miR-374a-3p and DNMT3A were detected by RT-PCR.
View Article and Find Full Text PDFOwing to the unique electronic spin properties, nitrogen-vacancy (NV) centers hosted in diamond have emerged as a powerful quantum tool for detecting various physical parameters and biological species. In this work, an optical-fiber quantum probe, configured by chemically modifying nanodiamonds on the surface of a cone fiber tip, is developed. Based on the continuous-wave optically detected magnetic resonance method and lock-in amplification technique, it is found that the sensing performance of probes can be engineered by varying the nanodiamond dispersion concentration and modification duration during the chemical modification process.
View Article and Find Full Text PDFArmed with the merits of one-dimensional nanostructures (flexibility, high aspect ratio, and anisotropy) and metals (high conductivity, plasmonic properties, and catalytic activity), metal nanowires (MNWs) have stood out as a new class of nanomaterials in the last two decades. They are envisaged to expedite significantly and even revolutionize a broad spectrum of applications related to display, sensing, energy, plasmonics, photonics, and catalysis. Compared with disordered MNWs, well-organized MNWs would not only enhance the intrinsic physical and chemical properties, but also create new functions and sophisticated architectures of optoelectronic devices.
View Article and Find Full Text PDFA high-performance surface plasmon resonance (SPR) fiber sensor is proposed with hyperbolic metamaterials (HMMs), nanodiamonds (NDs), and polydimethylsiloxane (PDMS) to enhance the temperature sensitivity and response time. The HMM with tunable dispersion can break through the structural limitations of the optical fiber to improve the refractive index (RI) sensitivity, while NDs and PDMS with large thermo-optic coefficients enable to induce significant RI change under varied thermal fields. The ternary composite endows the sensor with a high temperature sensitivity of -9.
View Article and Find Full Text PDFOne of the main causes of low back pain (LBP) and degenerative musculoskeletal disorders is intervertebral disc degeneration (IVDD). Inflammation-associated senescence of Human nucleus pulposus cells (HNPCs) plays an essential function in the disease progression of IVDD. Omentin-1 is an adipokine that has been recently reported to have anti-inflammatory potential.
View Article and Find Full Text PDFA tunable near-infrared surface plasmon resonance sensor based on graphene plasmons electrostatic gating control is investigated theoretically. Instead of the traditional refractive index sensing, the sensor can respond sensitively to the change of the chemical potential in graphene caused by the attachment of the analyte molecules. This feature can be potentially used for biological sensing with high sensitivity and high specificity.
View Article and Find Full Text PDFBiomed Opt Express
January 2022
Cucurbitacin E (CuE) plays an important role in anticancer, antichemical carcinogenesis, and body immunity, etc., and the detection of its concentration is meaningful to pharmacological studies and clinical applications. However, the small molecular weight of CuE makes direct detection difficult through a surface plasmon resonance (SPR) sensor.
View Article and Find Full Text PDFThe Vernier effect and harmonic Vernier effect have attracted ever-increasing interest due to their freely tailored spectrum envelope in tunable laser, modulator, and precision sensing. Most explorations have mainly focused on configuring two isolated optical resonators, namely the reference and tunable resonator. However, this configuration requires a stable reference resonator to guarantee robust readout, posing a significant challenge in applications.
View Article and Find Full Text PDFBackground: Elevated tumor necrosis factor alpha (TNF-α) expression is correlated with the progression of intervertebral disc degeneration (IVDD). Progranulin binding to tumor necrosis factor receptor (TNFR) and its derivative Atsttrin are effective for treating inflammatory arthritis. We hypothesize that Atsttrin has a protective effect in IVDD through different roles of TNFR receptor type 1 (TNFR1) and TNFR receptor type 2 (TNFR2) in degenerated discs.
View Article and Find Full Text PDFHigh sensitivity and capturing ratio are strongly demanded for surface plasmon resonance (SPR) sensors when applied in detection of small molecules. Herein, an SPR sensor is combined with a novel smart material, namely, MoS nanoflowers (MNFs), to demonstrate programmable adsorption/desorption of small bipolar molecules, i.e.
View Article and Find Full Text PDFA new mechanism between the temperature sensitivity and the length ratio of PMMA coating to no-core fiber (NCF) is reported to realize an optical fiber temperature sensor with ultra-high sensitivity and compact size by PMMA-coated no-core fiber. By both theory and experiment, it is found that the sensitivity has a linear response to the length ratio of PMMA coating to NCF rather than the conventional viewpoint that it depends on the length of PMMA. Based on this conclusion and the high thermo-optic coefficient of PMMA, the temperature sensitivity is significantly enhanced as high as -9.
View Article and Find Full Text PDFThis study was designed to study functions of Circ_0000020 during osteogenic differentiation. First, we used RT-qPCR to detect the expression of Circ_0000020, miR-142-5p and osteogenesis-related genes, whereas western blot analysis detected the expression of osteogenesis markers after the osteogenic differentiation of primary BMSCs isolated from rats. Alkaline phosphatase (ALP) activity and alizarin red Sstaining validated osteoblast phenotypes.
View Article and Find Full Text PDFIt has long been a challenge to develop strain sensors with large gauge factor (GF) and high transparency for a broad strain range, to which field silver nanowires (AgNWs) have recently been applied. A dense nanowire (NW) network benefits achieving large stretchability, while a sparse NW network favors realizing high transparency and sensitive response to small strains. Herein, a patterned AgNW-acrylate composite-based strain sensor is developed to circumvent the above trade-off issue via a novel ultrasonication-based patterning technique, where a water-soluble, UV-curable acrylate composite was blended with AgNWs as both a tackifier and a photoresist for finely patterning dense AgNWs to achieve high transparency, while maintaining good stretchability.
View Article and Find Full Text PDFHyperbolic metamaterials (HMMs) have attracted increasing attentions because of their unique dispersion properties and the flexibility to control the dispersion by changing the components and fractions of the composed materials. In this work, for the first time, we demonstrate a plasmonic sensor based on a side-polished few-mode-fiber coated with a layered of HMM, which is composed of alternating layers of Ag and TiO. To optimize the sensor performance, the effects of the metal filling fraction (ρ) and the number of bilayers (N) on the HMM dispersion are thoroughly engineered with the effective medium theory and the finite element method.
View Article and Find Full Text PDFThe ability to engineer microscale and nanoscale morphology upon metal nanowires (NWs) has been essential to achieve new electronic and photonic functions. Here, this study reports an optically programmable Plateau-Rayleigh instability (PRI) to demonstrate a facile, scalable, and high-resolution morphology engineering of silver NWs (AgNWs) at temperatures <150 °C within 10 min. This has been accomplished by conjugating a photosensitive diphenyliodonium nitrate with AgNWs to modulate surface-atom diffusion.
View Article and Find Full Text PDFA highly sensitive surface plasmon resonance fiber sensor for a vector magnetic field is proposed. The sensor is composed of a half-side gold-coated multimode-single-mode-multimode hetero-core fiber structure encapsulated with ferrofluids. The half-side gold film on the fiber not only produces the surface plasmon resonance, but also breaks the centrosymmetry of the light field in the fiber.
View Article and Find Full Text PDFPolarization-sensitive Tamm plasmons are investigated in a multi-layer photonic configuration where a monolayer black phosphorus (BP) is coated on a Bragg mirror separated by a dielectric. Owing to the in-plane anisotropy of BP, the Tamm plasmon can be excited selectively by tuning the BP carrier density. Cross-polarization conversion occurs when the armchair direction of BP makes an angle with the incident plan, i.
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