ENHANCEMENT OF SURFACE PLASMON RESONANCE USING COLLOIDAL GOLD NANOPARTICLES EMBEDDED IN A SILICA LAYER

정재연,최재유,JIE CHENG,박민성,조성인,현진호,박성하 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.5

This paper presents a strategy for the signal enhancement of surface plasmon resonance biosensors using colloidal gold nanoparticles and a silica layer. We describe the method for the deposition of a silica-stabilized gold nanoparticle layer on a gold film, namely an enhanced surface plasmon resonance chip. This chip shows significant changes in its surface plasmon resonance signals when biomolecules are attached to its surface as compared to a normal gold surface. These characteristics are closely related to the surface plasmon resonance effect as determined using prostate-specific antigen. The detection limit of the enhanced surface plasmon resonance chip is determined to be 0.01 ng/mL for a prostate-specific antigen immunoassay. The use of an enhanced surface plasmon resonance chip makes it possible to enhance signals 1000-fold compared to the signals obtained by conventional surface plasmon resonance sensing. The enhancement of the surface plasmon resonance spectral shift results from the coupling of the surface and particle plasmons through the application of a silica-stabilized gold nanoparticle layer on the gold surface.

Tunable Plasmonic Cavity for Label-free Detection of Small Molecules

Kwon, Jung A,Jin, Chang Min,Shin, Yonghee,Kim, Hye Young,Kim, Yura,Kang, Taewook,Choi, Inhee American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.15

<P>Owing to its high sensitivity and high selectivity along with rapid response time, plasmonic detection has gained considerable interest in a wide variety of sensing applications. To improve the fieldwork applicability and reliability of plasmonic detection, the integration of plasmonic nanoparticles into optical devices is desirable. Herein, we propose an integrated label-free detection platform comprising a plasmonic cavity that allows sensitive molecular detection via either surface-enhanced Raman scattering (SERS) or plasmon resonance energy transfer (PRET). A small droplet of metal ion solution spontaneously produces a plasmonic cavity on the surface of uncured poly(dimethylsiloxane) (PDMS), and as PDMS is cured, the metal ions are reduced to form a plasmonic antennae array on the cavity surface. Unique spherical feature and the integrated metallic nanoparticles of the cavity provide excellent optical functions to focus the incident light in the cavity and to rescatter the light absorbed by the nanoparticles. The optical properties of the plasmonic cavity for SERS or PRET are optimized by controlling the composition, size, and density of the metal nanoparticles. By using the cavity, we accomplish both 1000-fold sensitive detection and real-time monitoring of reactive oxygen species secreted by live cells via PRET. In addition, we achieve sensitive detection of trace amounts of toxic environmental molecules such as 5-chloro-2-methyl-4-isothiazolin-3-one/2-methyl-4-isothiazol-3-one (CMIT/MIT) and bisphenol A, as well as several small biomolecules such as glucose, adenine, and tryptophan, via SERS.</P> [FIG OMISSION]</BR>

Plasmonic effects of tailor-designed Au-TiO₂ nanostructures on the dye-sensitized solar cells

장윤희,김동하 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

Plasmonic metal nanoparticles (NPs) have widely applied in various research fields such as optoelectronics, optical sensor, catalysts, and surface-enhanced Raman scattering due to their unique electronics and optical properties. Particularly, the feature of localized surface plasmon resonance (LSPR) can be potentially utilized in peculiar plasmonic solar cells to enhance the light harvesting and charge carrier generation depending on strong light scattering effect, local field enhancement, and plasmon energy transfer mechanisms. Here, we introduced plasmonic core-shell structures consisting mutually antagonistic Au@TiO₂ core-shell structures (e.g., SiO₂@Au@TiO₂ or SiO₂@TiO₂@Au) to systematically investigate the plasmonic effects in solar cells. Surface plasmon resonance supported by the use of metallic nanostructures led to plasmon-enhanced dye excitation and photocurrent generation, resulting in enhanced photovoltaic performance.

Nanoplasmonic Alloy of Au/Ag Nanocomposites on Paper Substrate for Biosensing Applications

Park, Moonseong,Hwang, Charles S. H.,Jeong, Ki-Hun American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.1

<P>Plasmonic alloy has attracted much interest in tailoring localized surface plasmon resonance (LSPR) for recent biosensing techniques. In particular, paper-based plasmonic substrates allow capillary-driven lateral flow as well as three-dimensional metal nanostructures, and therefore they become actively transferred to LSPR-based biosensing such as surface-enhanced Raman spectroscopy (SERS) or metal-enhanced fluorescence (MEF). However, employing plasmonic alloy nanoislands on heat-sensitive substrate is still challenging, which significantly inhibits broad-range tailoring of the plasmon resonance wavelength (PRW) for superior sensitivity. Here we report paper-based plasmonic substrate with plasmonic alloy of Au/Ag nanocomposites for highly sensitive MEF and SERS biosensing applications. The nanofabrication procedures include concurrent deposition of Au and Ag below 100 °C without any damage on cellulose fibers. The Au/Ag nanocomposites feature nanoplasmonic alloy with single plasmon peak as well as broad-range tunability of PRW by composition control. This paper-based plasmonic alloy substrate enables about twofold enhancement of fluorescence signals and selective MEF after paper chromatography. The experimental results clearly demonstrate extraordinary enhancement in SERS signals for picomolar detection of folic acid as a cancer biomarker. This new method provides huge opportunities for fabricating plasmonic alloy on heat-sensitive substrate and biosensing applications.</P> [FIG OMISSION]</BR>

A polymer surface for antibody detection by using surface plasmon resonance via immobilized antigen

Chokchai Puttharugsa,Thidarat Wangkam,Nongluck Houngkamhang,Sirisa Yodmongkol,Oraprapai Gajanandana,Orawan Himananto,Boonsong Sutapun,Ratthasart Amarit,Armote Somboonkaew,Toemsak Srikhirin 한국물리학회 2013 Current Applied Physics Vol.13 No.6

A polymer substrate based surface plasmon resonance (SPR) technique was developed for detection of specific monoclonal antibody 10B2 (MAb 10B2) against bacterium Acidovorax avenae subsp. citrulli (Aac). The monolayer of Aac antigen was physically immobilized on 95:5 polystryrene e copoly acrylic acid (95PSMA) for detection of antibody. The amount of antigeneantibody binding was found to depend on the surface density of immobilized Aac on the sensor surface and the antibody concentration. The detection limit was 5 mg/ml which was lower than the required concentration during the normal production of the antibody at 10-100 mg/ml. This suggests a possible use of surface for the antibody screening. Moreover, an application in antibody screening was explored by combination of surface plasmon resonance imaging (SPR imaging) and antibody detection assay on the 95PSMA surface. Two antigens of bovine serum albumin (BSA) and Aac were used as a model system for antibody screening. The result shows that both antibodies can be distinguished using the immobilized antigens on the 95PSMA surface based SPR imaging technique.

3차원 FDTD Simulation을 이용한 자기조립된 Ag 나노입자의 국소표면플라즈몬공명 상호작용 현상 연구

이경민,윤순길,정종율,Lee, Kyung-Min,Yoon, Soon-Gil,Jeong, Jong-Ryul 한국재료학회 2014 한국재료학회지 Vol.24 No.8

In this study, we investigated localized surface plasmon resonance and the related coupling phenomena with respect to various geometric parameters of Ag nanoparticles, including the size and inter-particle distance. The plasmon resonances of Ag nanoparticles were studied using three-dimensional finite difference time domain(FDTD) calculations. From the FDTD calculations, we discovered the existence of a symmetric and an anti-symmetric plasmon coupling modes in the coupled Ag nanoparticles. The dependence of the resonance wavelength with respect to the inter-particle distance was also investigated, revealing that the anti-symmetric mode is more closely correlated with the inter-particle distance of the Ag nanoparticles than the symmetric mode. We also found that higher order resonance modes are appeared in the extinction spectrum for closely spaced Ag nanoparticles. Plasmon resonance calculations for the Ag particles coated with a $SiO_2$ layer showed enhanced plasmon coupling due to the strengthened plasmon resonance, suggesting that the inter-particle distance of the Ag nanoparticles can be estimated by measuring the transmission and absorption spectra with the plasmon resonance of symmetric and anti-symmetric localized surface plasmons.

Microstructures and Linear/Nonlinear Optical Properties of Monolayered Silver Nanoparticles

G. J. Lee,Y.P. Lee,C. S. Yoon 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.6

We investigated the microstuctural properties, as well as the linear and the nonlinear optical properties of silver nanoparticles embedded within a polymer matrix. The monolayered silver nanoparticles were fabricated by using a thermal treatment of thin silver films sandwiched between two polyimide (PI) precursor films. From the transmission electron microscopy images of the PImatrix-embedded silver nanoparticles, we found that silver nanoparticles arranged in a monolayer were formed within the polymer matrix. The average diameter (D) and the volume fraction (f) of silver nanoparticles depended on the silver film thickness (t) before undergoing thermal treatment: D = 5.0 nm (f = 14 %) and D = 11.8 nm (32 %) for sample A (t = 2.5 nm) and sample B (t = 10 nm), respectively. The monolayered silver nanoparticles exhibited a surface plasmon effect with tunable resonance wavelengths: λSPR = 464 nm (D = 5.0 nm, f = 14 %) and λ SPR = 523 nm (D = 11.8 nm, f = 32 %). The variation in the surface plasmon resonance wavelengths (λSPR) for the two different silver nanoparticles could be described by applying the Maxwell-Garnett effectivemedium approximation to the composite material. From the Z-scan experiment, we obtained the two-photon-absorption coefficients ( β ) of the two different samples: β = 2.4 × 10−7 cm/W (D = 5.0 nm, f = 14 %, λSPR = 464 nm) and β = 1.0 × 10−7 cm/W (D = 11.8 nm, f = 32 %, λSPR = 523 nm). The optical nonlinearity of silver nanoparticles is thought to be attributed to a two-photon-absorption-induced plasmonic resonance. We investigated the microstuctural properties, as well as the linear and the nonlinear optical properties of silver nanoparticles embedded within a polymer matrix. The monolayered silver nanoparticles were fabricated by using a thermal treatment of thin silver films sandwiched between two polyimide (PI) precursor films. From the transmission electron microscopy images of the PImatrix-embedded silver nanoparticles, we found that silver nanoparticles arranged in a monolayer were formed within the polymer matrix. The average diameter (D) and the volume fraction (f) of silver nanoparticles depended on the silver film thickness (t) before undergoing thermal treatment: D = 5.0 nm (f = 14 %) and D = 11.8 nm (32 %) for sample A (t = 2.5 nm) and sample B (t = 10 nm), respectively. The monolayered silver nanoparticles exhibited a surface plasmon effect with tunable resonance wavelengths: λSPR = 464 nm (D = 5.0 nm, f = 14 %) and λ SPR = 523 nm (D = 11.8 nm, f = 32 %). The variation in the surface plasmon resonance wavelengths (λSPR) for the two different silver nanoparticles could be described by applying the Maxwell-Garnett effectivemedium approximation to the composite material. From the Z-scan experiment, we obtained the two-photon-absorption coefficients ( β ) of the two different samples: β = 2.4 × 10−7 cm/W (D = 5.0 nm, f = 14 %, λSPR = 464 nm) and β = 1.0 × 10−7 cm/W (D = 11.8 nm, f = 32 %, λSPR = 523 nm). The optical nonlinearity of silver nanoparticles is thought to be attributed to a two-photon-absorption-induced plasmonic resonance.

Plasmonic nanoparticles at the periphery of poly(4-vinylpyridine) shell in core@shell nanostructures for localized surface plasmon resonance-based sensing and electrocatalysis

이지은,김동하 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

Bimetallic Core@shell nanoparticles have demonstrated distinctly different properties and potential uses in electronics, magnetics, catalysts, optics, and sensors. Their versatility in a wide range of applications stems from their unique physical and chemical properties directly related to particle size, shape, and interparticle distance and surface properties. The unique properties of the gold nanoparticles (AuNPs) are originated from the localized surface plasmon resonance (LSPR) phenomenon, the coupling of light into the resonant oscillation of charge density on the nanostructured noble metal surface. Core@shell type nanospheres have also been utilized as a platform for integration of functionalities into both the core and shell. The interaction between two types of metal NPs selectively located in the core and shell may alter the LSPR property, depending on the relative amount of the two metal components, the relative distance between them and the shell thickness. We suggest a unique strategy to generate core@shell nanoparticles based on pH-sensitive AuNPs decorated with polymer shell. Concretely, pH-sensitive AuNPs having P4VP on the surface were first fabricated through SI-ATRP. Then, they were mixed with selected metal precursor solutions followed by reduction using reducing agent. The metal NPs thus incorporated were distributed uniformly in the P4VP polymer shells. We investigate the structural change during the sequential synthetic process. The bimetallic nanostructures of AuNP@P4VP nanocomposites containing another type of metal NP at the P4VP periphery exhibit a controlled sensing property in terms of the change in the refractive index of surrounding media and a typical electrocatalytic activity for methanol oxidation reaction.

Surface Plasmon Resonance-Based Assay for Potency of a Monoclonal Antibody Drug

Jounghee Baek,Heesung Shin,Hyoung Kyoung Choi,Joon Ho Eom,Seung-rel Ryu,Soo Kyung Suh 한국에프디시규제과학회(구 한국에프디시법제학회) 2016 FDC법제연구 Vol.11 No.2

부가층의 두께 차이를 이용한 표면플라즈몬공명 멀티센싱

金榮圭(Young-Gyu Kim),吳明煥(Myung-Hwan Oh),李承起(Seung-Ki Lee) 대한전기학회 2006 전기학회논문지C Vol.55 No.10

A novel surface plasmon resonance(SPR) multisensing method, which does not require imaging apparatus such as CCD, has been proposed and implemented experimentally. The proposed method is based on the multichannel SPR and the separation of signals by use of additional layers whose thickness is controlled. SPR signals are influenced by the thickness of sensing layer as well as the optical condition of sensing surface. As the SPR signals from different ligands are usually positioned closely, the reflected light from sensing surface does not provide us with the clear differences of resonance signal depending on the kinds of ligands. It was found from our experiments that SPR signals from each ligand that is located on the additional layer with different thickness can be separated clearly enough to identify various signals from different ligands. Proposed method with theoretical design and simulation has been verified experimentally by using SiO₂ thin film layer as additional layer.