Colored Cellulose Nanoparticles with High Stability and Easily Modified Surface for Accurate and Sensitive Multiplex Lateral Flow Assay

ACS Nano, Год журнала: 2025, Номер unknown

Опубликована: Янв. 23, 2025

Decentralized testing using multiplex lateral flow assays (mLFAs) to simultaneously detect multiple analytes can significantly enhance detection efficiency, reduce cost and time, improve analytic accuracy. However, the challenges, including monochromatic color of probe particles, interference between different test lines, reduced specificity sensitivity, severely hinder mLFAs from wide use. In this study, we prepared polydopamine (PDA)-coated dyed cellulose nanoparticles (dCNPs@P) with tunable colors as for mLFAs. Cellulose (CNPs) were synthesized uniform spheric shapes sizes. Dye molecules loaded on CNPs via a mature industrial dyeing method. The PDA shell provided reactive surface facile receptor conjugation protected dye leaking. dCNPs@P displayed higher signal intensity than gold nanoparticles. They also had stability tolerate salt varied pH. dCNP@P-based successfully applied mycotoxins in cereals determine levels inflammatory biomarkers differentiate viral bacterial infections. tests represented high accuracy more sensitive quantified was accessible by measuring intensities colorimetric or photothermal signals. Overall, study provides practical system solution based colored dCNPs@P.

Язык: Английский

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Improving Sensitivity and Reproducibility of Surface-Enhanced Raman Scattering Biochips Utilizing Magnetoplasmonic Nanoparticles and Statistical Methods

ACS Sensors, Год журнала: 2024, Номер 9(1), С. 305 - 314

Опубликована: Янв. 15, 2024

Surface-enhanced Raman scattering (SERS) technology has been widely recognized for its remarkable sensitivity in biochip development. This study presents a novel sandwich immunoassay that synergizes SERS with magnetoplasmonic nanoparticles (MPNs) to improve sensitivity. By taking advantage of the unique magnetism these nanoparticles, we further enhance detection biochips through applied magnetic field. Despite high sensitivity, practical applications are often limited by issues stability and reproducibility. In this study, introduced straightforward statistical method known as "Gaussian binning", which involves initially binning two-dimensional mapping data subsequently applying Gaussian fitting. approach enables more consistent reliable interpretation reducing variability inherent signal measurements. Based on our method, biochip, targeting C-reactive protein (CRP), achieves an impressive limit 5.96 fg/mL, application 3700 G field, it enhances 5.7 times, reaching 1.05 fg/mL. Furthermore, highly sensitive magnetically tunable is easily designed versatile adaptability, enabling other proteins. We believe innovation holds promise enhancing clinical applicability biochips.

Язык: Английский

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Near-Field Terahertz Morphological Reconstruction Nanoscopy for Subsurface Imaging of Protein Layers

ACS Nano, Год журнала: 2024, Номер 18(14), С. 10104 - 10112

Опубликована: Март 25, 2024

Protein layers formed on solid surfaces have important applications in various fields. High-resolution characterization of the morphological structures protein forms process developing has significant implications for control layer's quality as well evaluation performance. However, it remains challenging to precisely characterize all possible forms, including individuals, networks, and involved formation with currently available methods. Here, we report a terahertz (THz) reconstruction nanoscopy (THz-MRN), which can reveal nanoscale three-dimensional structural information sample from its THz near-field image by exploiting an extended finite dipole model thin sample. THz-MRN allows both surface imaging subsurface vertical resolution ∼0.5 nm, enabling proteins at single-molecule level. We demonstrate single immunoglobulin G (IgG) molecules, their monolayer, heterogeneous double layer comprising IgG monolayer horseradish peroxidase-conjugated anti-IgG layer. The established presents useful approach label-free nondestructive study layers.

Язык: Английский

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Bound state in the continuum (BIC) excited by the metasurface breaking in-plane symmetry and quasi-BIC for terahertz sensing

Applied Physics Letters, Год журнала: 2024, Номер 124(23)

Опубликована: Июнь 3, 2024

Bound state in the continuum (BIC), generally realized by structures with in-plane symmetry, has been under spotlight control of electromagnetic field. This Letter presents a terahertz metasurface that possesses broken symmetry for exciting BIC. The switch from BIC to quasi-BIC can be achieved through parameter modulation. According multipolar decomposition, is constructed destructive interference far-field radiation originating electric dipole and magnetic quadrupole. More importantly, considering metal material finite conductivity, we analyze relationship between non-radiation losses, based on time domain coupled mode theory, which provides substantial theoretical support investigation phenomena. Furthermore, proposed highly sensitive changes dielectric environment, resulting high sensitivity 135 GHz/RIU distinction sucrose glucose same solid content. As result, our research explanation evolution excited structure promotes development high-performance meta-device used sensing.

Язык: Английский

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Efficient polarization-insensitive quasi-BIC modulation by VO₂ thin films

Optics Express, Год журнала: 2024, Номер 32(4), С. 5862 - 5862

Опубликована: Янв. 18, 2024

Bound states in the continuum (BIC) offer great design freedom for realizing high-quality factor metasurfaces. By deliberately disrupting inherent symmetries, BIC can degenerate into quasi-BIC exhibiting sharp spectra with strong light confinement. This transformation has been exploited to develop cutting-edge sensors and modulators. However, most proposed quasi-BICs metasurfaces are composed of unit cells C

Язык: Английский

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Gold nanoparticle-modified single-walled carbon nanotube terahertz metasurface for ultrasensitive sensing of trace proteins

Talanta, Год журнала: 2025, Номер 286, С. 127549 - 127549

Опубликована: Янв. 6, 2025

Язык: Английский

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Metasurface-Enabled Microphotonic Biosensors via BIC Modes

Photonics, Год журнала: 2025, Номер 12(1), С. 48 - 48

Опубликована: Янв. 8, 2025

Photonic biosensors based on bound states in the continuum (BIC) resonant modes exhibit a transformative potential for high-sensitivity, label-free detection across various diagnostic applications. BIC-enabled metasurfaces, utilizing dielectric, plasmonic, and hybrid structures, achieve ultra-high Q-factors amplify target molecule interactions functionalized sensor surfaces. These unique properties result increased refractive index sensitivity low limits, essential monitoring biomolecules clinical diagnostics, environmental analysis, food safety. Recent advancements metasurfaces have demonstrated ultra-low limits zeptomolar range, making these devices highly promising real-world This review paper critically discusses design principles of BIC-based biosensors, emphasizing key factors such as material selection, structural asymmetry, functionalization strategies that enhance both specificity. Additionally, recent fabrication techniques enable precise BIC control with scalable approaches practical biosensing applications are examined. Case studies demonstrate effectiveness real-time, low-concentration detection, highlighting their versatility adaptability. Finally, future challenges opportunities, integration microfluidics point-of-care testing multiplexed sensing, underscoring platforms to revolutionize field biosensing.

Язык: Английский

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Reconfigurable Terahertz Metamaterials Based on the Refractive Index Change of Epitaxial Vanadium Dioxide Films Across the Metal–Insulator Transition

Nanomaterials, Год журнала: 2025, Номер 15(6), С. 439 - 439

Опубликована: Март 13, 2025

The intrinsic metal–insulator transition (MIT) of VO2 films near room temperature presents significant potential for reconfigurable metamaterials in the terahertz (THz) frequency range. While previous designs primarily focused on changes electrical conductivity across MIT, accompanying dielectric due to mesoscopic carrier confinement effect have been largely unexplored. In this study, we integrate asymmetric split-ring resonators 35 nm epitaxial film and identify a “dielectric window” at early stages MIT. This is characterized by redshift resonant without degradation quality. phenomenon attributed an inhomogeneous phase film, which induces purely change onset while occurs later, slightly above percolation threshold. Our findings provide deeper insights into THz properties pave way dielectric-based, hybrid metamaterials.

Язык: Английский

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Polarization‐Controlled Non‐Hermitian Metasurfaces for Ultra‐Sensitive Terahertz Sensing

Laser & Photonics Review, Год журнала: 2025, Номер unknown

Опубликована: Март 31, 2025

Abstract Non‐Hermitian systems offer significant advantages in sensing technology, with most studies primarily focused on exceptional points. However, the extreme sensitivity near these points poses great challenges due to fabrication errors and system noises, which degrade performance. To address this, a novel approach is introduced that leverages polarization degrees of freedom non‐Hermitian systems. A direct relation between incident angle transmission phase coupled metasurface achieved polarization‐controlled singularity even post‐fabrication achieved. In addition, utilized as index, enables indirect accurate measurement. The theoretical experimentally validated using general design THz sensors. method enhances robustness sensitivity, opening new avenues for practical applications ultra‐sensitive sensing.

Язык: Английский

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Enhanced Terahertz Specific Sensing for Alzheimer’s Marker by Metasurface-Analyte Union Modification on Microfluidic Sensor

IEEE Sensors Journal, Год журнала: 2024, Номер 24(6), С. 7690 - 7699

Опубликована: Фев. 1, 2024

Metasurface (MS)-based terahertz (THz) biosensors have attracted significant attention in the biological field due to their nondestructive and harmless interaction with biochemical samples. However, it is still challenging for specific detection mixed samples via THz metasensors. In this work, we modified MS chips target biomolecules, respectively, utilized immune binding gold nanorods (GNRs), achieved high-sensitive Alzheimer's marker $\text{A}\beta _{\text {1-42}}$ protein a microfluidic platform. A double-ring coupled metallic that can provide strong localized enhancement was fabricated then -antibody by covalent capture . Moreover, GNRs were introduced bind , sensor's response greatly enhanced. Through sensor-analytes modification, sensitivity of sensor reach 240.91 GHz notation="LaTeX">$\cdot $ mL/nmol, limit (LoD) one order magnitude higher than without GNRs. addition, LoD reached 0.2 pmol/mL (1 ng/mL), which 100 times other nonspecific proteins. More importantly, biosensor also recognize sample physiological limiting concentration. Our high selectivity nanomaterial-MS hybrid-based would give access rich applications label-free biosensing.

Язык: Английский

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