The Experts below are selected from a list of 141 Experts worldwide ranked by ideXlab platform
Gang Logan Liu - One of the best experts on this subject based on the ideXlab platform.
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Colorimetric imaging of layer-by-layer molecular deposition on nanoplasmonic Lycurgus Cup array
Sensors and Actuators B: Chemical, 2018Co-Authors: Abid Ameen, Austin Hsiao, Gang Logan LiuAbstract:Abstract A quantitative label-free colorimetric imaging of biochemical molecular thin film deposition at a single molecule layer (2 nm thickness) resolution was demonstrated on a nanoplasmonic sensor substrate known as nano Lycurgus Cup array (nanoLCA) and the penetration depth of the nanoplasmonic sensor was accordingly determined. Colorimetric nanoplasmonic imaging technique provides significant advantages in direct visualization and quick identification of surface deposited molecules. We implement layer by layer deposition of alternating polyelectrolyte layers with controlled thickness on the nanoLCA device to show surface color changes and determine the decay length of the device derived from the sensor spectral response to the molecular layer thickness. The calculated decay length of the nanoLCA device is 193 nanometers which corresponds well with the decay length of other known surface plasmon sensors. In addition micro contact molecular printing and transferring on the nanoLCA surface is used to selectively deposit poly- l -lysine and different alkanethiol molecules to demonstrate direct colorful visualization of surface patterned unlabeled molecules.
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Intensified surface enhanced Raman signal of a graphene monolayer on a plasmonic substrate through the use of fluidic dielectrics
Plasmonics in Biology and Medicine XIV, 2017Co-Authors: Amirreza Mahigir, Gang Logan Liu, Manas Ranjan Gartia, Te Wei Chang, Georgios VeronisAbstract:It has been shown that surface enhanced Raman spectroscopy (SERS) has many promising applications in ultrasensitive detection of Raman signal of substances. However, optimizing the enhancement in SERS signal for different applications typically requires several levels of fabrication of active plasmonic SERS substrates. In this paper, we report the enhancement of SERS signal of a single layer of graphene located on a plasmonic nano-Lycurgus Cup array after placing water droplets on it. The experimental data shows that addition of water droplets can enhance the SERS signal of the single layer of graphene about 10 times without requiring any modifications to the nano-Lycurgus Cup array. Using fullwave electromagnetic simulations, we show that addition of water droplets enhances the local electric field at the graphene layer, resulting in stronger light-graphene interaction at the excitation pump laser wavelength. We also show that the addition of water droplets on the graphene layer enables us to modify the band diagram of the structure, in order to enhance the local density of optical states at the Raman emission wavelengths of the graphene layer. Numerical calculations of both the excitation field enhancement at the location of the graphene layer, and the emission enhancement due to enhanced local density of optical states, support the experimental results. Our results demonstrate an approach to boost the SERS signal of a target material by controlling the band diagram of the active nanostructured SERS substrate through the use of fluidic dielectrics. These results could find potential applications in biomedical and environmental technologies.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
Analytical chemistry, 2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore's absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system.
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Sensitivity Tuning through Additive Heterogeneous Plasmon Coupling between 3D Assembled Plasmonic Nanoparticle and NanoCup Arrays
Small (Weinheim an der Bergstrasse Germany), 2016Co-Authors: Sujin Seo, Xiangfei Zhou, Gang Logan LiuAbstract:Plasmonic substrates have fixed sensitivity once the geometry of the structure is defined. In order to improve the sensitivity, significant research effort has been focused on designing new plasmonic structures, which involves high fabrication costs; however, a method is reported for improving sensitivity not by redesigning the structure but by simply assembling plasmonic nanoparticles (NPs) near the evanescent field of the underlying 3D plasmonic nanostructure. Here, a nanoscale Lycurgus Cup array (nanoLCA) is employed as a base colorimetric plasmonic substrate and an assembly template. Compared to the nanoLCA, the NP assembled nanoLCA (NP-nanoLCA) exhibits much higher sensitivity for both bulk refractive index sensing and biotin-streptavidin binding detection. The limit of detection of the NP-nanoLCA is at least ten times smaller when detecting biotin-streptavidin conjugation. The numerical calculations confirm the importance of the additive plasmon coupling between the NPs and the nanoLCA for a denser and stronger electric field in the same 3D volumetric space. Tunable sensitivity is accomplished by controlling the number of NPs in each nanoCup, or the number density of the hot spots. This simple yet scalable and cost-effective method of using additive heterogeneous plasmon coupling effects will benefit various chemical, medical, and environmental plasmon-based sensors.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore’s absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system
Manas Ranjan Gartia - One of the best experts on this subject based on the ideXlab platform.
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Intensified surface enhanced Raman signal of a graphene monolayer on a plasmonic substrate through the use of fluidic dielectrics
Plasmonics in Biology and Medicine XIV, 2017Co-Authors: Amirreza Mahigir, Gang Logan Liu, Manas Ranjan Gartia, Te Wei Chang, Georgios VeronisAbstract:It has been shown that surface enhanced Raman spectroscopy (SERS) has many promising applications in ultrasensitive detection of Raman signal of substances. However, optimizing the enhancement in SERS signal for different applications typically requires several levels of fabrication of active plasmonic SERS substrates. In this paper, we report the enhancement of SERS signal of a single layer of graphene located on a plasmonic nano-Lycurgus Cup array after placing water droplets on it. The experimental data shows that addition of water droplets can enhance the SERS signal of the single layer of graphene about 10 times without requiring any modifications to the nano-Lycurgus Cup array. Using fullwave electromagnetic simulations, we show that addition of water droplets enhances the local electric field at the graphene layer, resulting in stronger light-graphene interaction at the excitation pump laser wavelength. We also show that the addition of water droplets on the graphene layer enables us to modify the band diagram of the structure, in order to enhance the local density of optical states at the Raman emission wavelengths of the graphene layer. Numerical calculations of both the excitation field enhancement at the location of the graphene layer, and the emission enhancement due to enhanced local density of optical states, support the experimental results. Our results demonstrate an approach to boost the SERS signal of a target material by controlling the band diagram of the active nanostructured SERS substrate through the use of fluidic dielectrics. These results could find potential applications in biomedical and environmental technologies.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
Analytical chemistry, 2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore's absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore’s absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system
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bifunctional nano Lycurgus Cup array plasmonic sensor for colorimetric sensing and surface enhanced raman spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
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Substrate binding to cytochrome P450-2J2 in Nanodiscs detected by nanoplasmonic Lycurgus Cup arrays
Biosensors & bioelectronics, 2015Co-Authors: Lisa Plucinski, Gang Logan Liu, Manas Ranjan Gartia, Austin Hsiao, Abid Ameen, Te Wei Chang, William R. Arnold, Aditi DasAbstract:Cytochrome P450s are the primary enzymes involved in phase I drug metabolism. They are an important target for early drug discovery research. However, high-throughput drug screening of P450s is limited by poor protein stability and lack of consistent measurement of binding events. Here we present the detection of substrate binding to cytochrome P450-2J2 (CYP2J2), the predominant P450 in the human heart, using a combination of Nanodisc technology and a nanohole plasmonic sensor called nanoplasmonic Lycurgus Cup array (nanoLCA). The Nanodisc, a nanoscale membrane bilayer disc, is used to stabilize the protein on the metallic plasmonic surface. Absorption spectroscopy of seven different substrates binding to CYP2J2 in solution showed that they are all type I, resulting in shifting of the protein bands to lower wavelengths (blue shift). Detection on the nanoLCA sensor also showed spectral blue shifts of CYP2J2 following substrate binding. Finite Difference Time Domain (FDTD) electromagnetic simulation suggested that the blue shift on the nanoLCA is because of the hybridization of plasmon polariton Bloch wave and the electronic resonance of the heme group of CYP2J2. We found the plasmonic properties of the nanoLCA sensor to be highly reproducible, which allowed comparisons among the different substrates at different concentrations. Further, due to the unique spectral properties of the nanoLCA sensor, including the transmission of a single color, we were able to perform colorimetric detection of the binding events. These results indicate that a resonance plasmonic sensing mechanism can be used to distinguish between different substrates of the same binding type at different concentrations binding to P450s and that the nanoLCA sensor has the potential to provide consistent high-throughput measurements of this system.
Te Wei Chang - One of the best experts on this subject based on the ideXlab platform.
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Intensified surface enhanced Raman signal of a graphene monolayer on a plasmonic substrate through the use of fluidic dielectrics
Plasmonics in Biology and Medicine XIV, 2017Co-Authors: Amirreza Mahigir, Gang Logan Liu, Manas Ranjan Gartia, Te Wei Chang, Georgios VeronisAbstract:It has been shown that surface enhanced Raman spectroscopy (SERS) has many promising applications in ultrasensitive detection of Raman signal of substances. However, optimizing the enhancement in SERS signal for different applications typically requires several levels of fabrication of active plasmonic SERS substrates. In this paper, we report the enhancement of SERS signal of a single layer of graphene located on a plasmonic nano-Lycurgus Cup array after placing water droplets on it. The experimental data shows that addition of water droplets can enhance the SERS signal of the single layer of graphene about 10 times without requiring any modifications to the nano-Lycurgus Cup array. Using fullwave electromagnetic simulations, we show that addition of water droplets enhances the local electric field at the graphene layer, resulting in stronger light-graphene interaction at the excitation pump laser wavelength. We also show that the addition of water droplets on the graphene layer enables us to modify the band diagram of the structure, in order to enhance the local density of optical states at the Raman emission wavelengths of the graphene layer. Numerical calculations of both the excitation field enhancement at the location of the graphene layer, and the emission enhancement due to enhanced local density of optical states, support the experimental results. Our results demonstrate an approach to boost the SERS signal of a target material by controlling the band diagram of the active nanostructured SERS substrate through the use of fluidic dielectrics. These results could find potential applications in biomedical and environmental technologies.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
Analytical chemistry, 2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore's absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore’s absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system
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bifunctional nano Lycurgus Cup array plasmonic sensor for colorimetric sensing and surface enhanced raman spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
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Substrate binding to cytochrome P450-2J2 in Nanodiscs detected by nanoplasmonic Lycurgus Cup arrays
Biosensors & bioelectronics, 2015Co-Authors: Lisa Plucinski, Gang Logan Liu, Manas Ranjan Gartia, Austin Hsiao, Abid Ameen, Te Wei Chang, William R. Arnold, Aditi DasAbstract:Cytochrome P450s are the primary enzymes involved in phase I drug metabolism. They are an important target for early drug discovery research. However, high-throughput drug screening of P450s is limited by poor protein stability and lack of consistent measurement of binding events. Here we present the detection of substrate binding to cytochrome P450-2J2 (CYP2J2), the predominant P450 in the human heart, using a combination of Nanodisc technology and a nanohole plasmonic sensor called nanoplasmonic Lycurgus Cup array (nanoLCA). The Nanodisc, a nanoscale membrane bilayer disc, is used to stabilize the protein on the metallic plasmonic surface. Absorption spectroscopy of seven different substrates binding to CYP2J2 in solution showed that they are all type I, resulting in shifting of the protein bands to lower wavelengths (blue shift). Detection on the nanoLCA sensor also showed spectral blue shifts of CYP2J2 following substrate binding. Finite Difference Time Domain (FDTD) electromagnetic simulation suggested that the blue shift on the nanoLCA is because of the hybridization of plasmon polariton Bloch wave and the electronic resonance of the heme group of CYP2J2. We found the plasmonic properties of the nanoLCA sensor to be highly reproducible, which allowed comparisons among the different substrates at different concentrations. Further, due to the unique spectral properties of the nanoLCA sensor, including the transmission of a single color, we were able to perform colorimetric detection of the binding events. These results indicate that a resonance plasmonic sensing mechanism can be used to distinguish between different substrates of the same binding type at different concentrations binding to P450s and that the nanoLCA sensor has the potential to provide consistent high-throughput measurements of this system.
Austin Hsiao - One of the best experts on this subject based on the ideXlab platform.
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Colorimetric imaging of layer-by-layer molecular deposition on nanoplasmonic Lycurgus Cup array
Sensors and Actuators B: Chemical, 2018Co-Authors: Abid Ameen, Austin Hsiao, Gang Logan LiuAbstract:Abstract A quantitative label-free colorimetric imaging of biochemical molecular thin film deposition at a single molecule layer (2 nm thickness) resolution was demonstrated on a nanoplasmonic sensor substrate known as nano Lycurgus Cup array (nanoLCA) and the penetration depth of the nanoplasmonic sensor was accordingly determined. Colorimetric nanoplasmonic imaging technique provides significant advantages in direct visualization and quick identification of surface deposited molecules. We implement layer by layer deposition of alternating polyelectrolyte layers with controlled thickness on the nanoLCA device to show surface color changes and determine the decay length of the device derived from the sensor spectral response to the molecular layer thickness. The calculated decay length of the nanoLCA device is 193 nanometers which corresponds well with the decay length of other known surface plasmon sensors. In addition micro contact molecular printing and transferring on the nanoLCA surface is used to selectively deposit poly- l -lysine and different alkanethiol molecules to demonstrate direct colorful visualization of surface patterned unlabeled molecules.
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bifunctional nano Lycurgus Cup array plasmonic sensor for colorimetric sensing and surface enhanced raman spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
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Substrate binding to cytochrome P450-2J2 in Nanodiscs detected by nanoplasmonic Lycurgus Cup arrays
Biosensors & bioelectronics, 2015Co-Authors: Lisa Plucinski, Gang Logan Liu, Manas Ranjan Gartia, Austin Hsiao, Abid Ameen, Te Wei Chang, William R. Arnold, Aditi DasAbstract:Cytochrome P450s are the primary enzymes involved in phase I drug metabolism. They are an important target for early drug discovery research. However, high-throughput drug screening of P450s is limited by poor protein stability and lack of consistent measurement of binding events. Here we present the detection of substrate binding to cytochrome P450-2J2 (CYP2J2), the predominant P450 in the human heart, using a combination of Nanodisc technology and a nanohole plasmonic sensor called nanoplasmonic Lycurgus Cup array (nanoLCA). The Nanodisc, a nanoscale membrane bilayer disc, is used to stabilize the protein on the metallic plasmonic surface. Absorption spectroscopy of seven different substrates binding to CYP2J2 in solution showed that they are all type I, resulting in shifting of the protein bands to lower wavelengths (blue shift). Detection on the nanoLCA sensor also showed spectral blue shifts of CYP2J2 following substrate binding. Finite Difference Time Domain (FDTD) electromagnetic simulation suggested that the blue shift on the nanoLCA is because of the hybridization of plasmon polariton Bloch wave and the electronic resonance of the heme group of CYP2J2. We found the plasmonic properties of the nanoLCA sensor to be highly reproducible, which allowed comparisons among the different substrates at different concentrations. Further, due to the unique spectral properties of the nanoLCA sensor, including the transmission of a single color, we were able to perform colorimetric detection of the binding events. These results indicate that a resonance plasmonic sensing mechanism can be used to distinguish between different substrates of the same binding type at different concentrations binding to P450s and that the nanoLCA sensor has the potential to provide consistent high-throughput measurements of this system.
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Bifunctional Nano Lycurgus Cup Array Plasmonic Sensor for Colorimetric Sensing and Surface‐Enhanced Raman Spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
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colorimetric plasmon resonance imaging using nano Lycurgus Cup arrays
Advanced Optical Materials, 2013Co-Authors: Manas Ranjan Gartia, Sujin Seo, Austin Hsiao, Anusha Pokhriyal, Gulsim Kulsharova, Brian T Cunningham, Tiziana C Bond, Gang Logan LiuAbstract:Lycurgus Cup [ 1 ] created by ancient Romans 2000 years ago can appear different colors depending on the direction of light illumination in which it is viewed due to metal nanoparticle optical scattering. It has inspired nanoplasmonics research over the past decade. [ 2–5 ] Here we present a nanoscale Lycurgus Cup arrays (nanoLCA) device that has the property of appearing green when light is shone on to it and changing the color to red without direct light illumination (see Supporting movie). The above colorimetric device fabricated on transparent plastic substrate consists of about one billion nano Lycurgus Cups in an array with subwavelength opening and decorated with metal nanoparticles on side walls. Strikingly different from metallic nanohole arrays [ 6 ] or quasi-3D plasmonic crystals [ 7 ] with extraordinary optical transmission which usually give rise to multiple transmission spectral features, nanoLCA exhibits metal nanoparticle-like single transmission wavelength peak in the whole visible ranges. Electromagnetic simulation revealed the plasmon resonance scattering modes of the metal nanoparticles on the Cup side walls and the corresponding single peak wavelength scattering light selectively transmitted by the nanoLCA. The huge transmission and refl ection wavelength shifts upon binding of molecules on our fl exible, high-throughput, large area nanoLCA device are up to 200 nm (with maximum sensitivity of 46000 nm per refractive-index unit (RIU) and fi gure of merit (FOM) of 1022), much greater than the typical nano particle plasmon resonance wavelength shift and large enough to detect the color differences directly by naked eyes and conventional bright fi eld microscopes. This enables to eliminate the need for precision spectrometer or fl uorescence labeling. We demonstrated the
Xinhao Wang - One of the best experts on this subject based on the ideXlab platform.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
Analytical chemistry, 2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore's absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system.
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Self-Referenced Smartphone-Based Nanoplasmonic Imaging Platform for Colorimetric Biochemical Sensing
2016Co-Authors: Xinhao Wang, Te Wei Chang, Manas Ranjan Gartia, Guohong Lin, Gang Logan LiuAbstract:Colorimetric sensors usually suffer due to errors from variation in light source intensity, the type of light source, the Bayer filter algorithm, and the sensitivity of the camera to incoming light. Here, we demonstrate a self-referenced portable smartphone-based plasmonic sensing platform integrated with an internal reference sample along with an image processing method to perform colorimetric sensing. Two sensing principles based on unique nanoplasmonics enabled phenomena from a nanostructured plasmonic sensor, named as nanoLCA (nano Lycurgus Cup array), were demonstrated here for colorimetric biochemical sensing: liquid refractive index sensing and optical absorbance enhancement sensing. Refractive indices of colorless liquids were measured by simple smartphone imaging and color analysis. Optical absorbance enhancement in the colorimetric biochemical assay was achieved by matching the plasmon resonance wavelength with the chromophore’s absorbance peak wavelength. Such a sensing mechanism improved the limit of detection (LoD) by 100 times in a microplate reader format. Compared with a traditional colorimetric assay such as urine testing strips, a smartphone plasmon enhanced colorimetric sensing system provided 30 times improvement in the LoD. The platform was applied for simulated urine testing to precisely identify the samples with higher protein concentration, which showed potential point-of-care and early detection of kidney disease with the smartphone plasmonic resonance sensing system
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bifunctional nano Lycurgus Cup array plasmonic sensor for colorimetric sensing and surface enhanced raman spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
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Bifunctional Nano Lycurgus Cup Array Plasmonic Sensor for Colorimetric Sensing and Surface‐Enhanced Raman Spectroscopy
Advanced Optical Materials, 2015Co-Authors: Te Wei Chang, Manas Ranjan Gartia, Austin Hsiao, Xinhao Wang, Guohong Lin, Xiangrong Liu, Gang Logan LiuAbstract:A bifunctional ultrasensitive nanoplasmonic sensor is demonstrated with combined surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS) sensing capabilities. Unlike traditional extraordinary transmission (EOT) devices, nano Lycurgus Cup array (nanoLCA) contains a hybrid configuration of periodic quasi-3D nanostructure array and dense sidewall metal nanoparticles within each nanostructure, which enables both refractive index sensing and SERS chemical identification on the same device with high sensitivity. The visible plasmon resonance sensitivity of nanoLCA is measured to be as high as 796 nm/RIU with the figure of merit (FOM) of 12.7 so that the device is applied for colorimetric liquid sensing with an ordinary microscopic system. Moreover, the SERS enhancement of the very same nanoLCA for liquid sample is calculated to be 2.8 × 107, which is the highest among all reported EOT-based SERS devices. The urea concentration detection has been demonstrated to show the complementary rapid colorimetric screening and precise SERS identification functions provided by nanoLCA plasmonic sensor for chemical analysis or biological diagnostics in a resource-limited environment.
