1
|
Turco A, Primiceri E, Chiriacò MS, La Pesa V, Ferrara F, Riva N, Quattrini A, Romano A, Maruccio G. Advancing amyotrophic lateral sclerosis disease diagnosis: A lab-on-chip electrochemical immunosensor for ultra-sensitive TDP-43 protein detection and monitoring in serum patients'. Talanta 2024; 273:125866. [PMID: 38490025 DOI: 10.1016/j.talanta.2024.125866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/22/2023] [Accepted: 02/29/2024] [Indexed: 03/17/2024]
Abstract
The global increase in population aging has led to a rise in neurodegenerative diseases (NDs), posing significant challenges to public health. Developing selective and specific biomarkers for early diagnosis and drug development is crucial addressing the growing burden of NDs. In this context, the RNA-binding protein TDP-43 has emerged as a promising biomarker for amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD), and TDP-43-associated proteinopathies. However, existing detection methods suffer from limitations such as cost, complexity, and operator dependence. Here, we present a novel electrochemical biosensor integrated into a lab-on-chip (LoC) platform to detect TDP-43. The sensor utilizes electrosynthesized polypyrrole derivatives with carboxylic groups for transducer functionalization, enabling targeted immobilization of TDP-43 antibodies. Differential pulsed voltammetry (DPV) is used for the indirect detection and quantification of TDP-43. The chip exhibits rapid response, good reproducibility, a linear detection range, and sensitivity from 0.01 ng/mL to 25 ng/mL of TDP-43 protein concentration with a LOD = 10 pg/mL. Furthermore, successful TDP-43 detection in complex matrices like serum of ALS patients and healthy individuals demonstrates its potential as a point-of-care diagnostic device. This electrochemical biosensor integrated into a chip offers good sensitivity, rapid response, and robust performance, providing a promising avenue for advancing neurodegenerative disease diagnostics and therapeutic development.
Collapse
Affiliation(s)
- Antonio Turco
- CNR Nanotec Institute of Nanotechnology, Via Monteroni, 73100, Lecce, Italy; IRCCS San Raffaele Scientific Institute, Neuropathology Unit, Institute of Experimental Neurology, 20132, Milan, Italy
| | | | | | - Velia La Pesa
- IRCCS San Raffaele Scientific Institute, Neuropathology Unit, Institute of Experimental Neurology, 20132, Milan, Italy
| | - Francesco Ferrara
- CNR Nanotec Institute of Nanotechnology, Via Monteroni, 73100, Lecce, Italy
| | - Nilo Riva
- IRCCS San Raffaele Scientific Institute, Neuropathology Unit, Institute of Experimental Neurology, 20132, Milan, Italy
| | - Angelo Quattrini
- IRCCS San Raffaele Scientific Institute, Neuropathology Unit, Institute of Experimental Neurology, 20132, Milan, Italy
| | - Alessandro Romano
- IRCCS San Raffaele Scientific Institute, Neuropathology Unit, Institute of Experimental Neurology, 20132, Milan, Italy
| | - Giuseppe Maruccio
- CNR Nanotec Institute of Nanotechnology, Via Monteroni, 73100, Lecce, Italy; Omnics Research Group, Department of Mathematics and Physics "Ennio De Giorgi", University of Salento, Via per Monteroni, 73100, Lecce, Italy
| |
Collapse
|
2
|
Lv X, Wu F, Tian Y, Zuo P, Li F, Xu G, Niu W. Engineering the Intrinsic Chirality of Plasmonic Au@Pd Metamaterials for Highly Sensitive Chiroplasmonic Hydrogen Sensing. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2305429. [PMID: 37528622 DOI: 10.1002/adma.202305429] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/14/2023] [Indexed: 08/03/2023]
Abstract
Metal helicoid nanoparticles with intrinsic 3D chiral structures have emerged as a new class of plasmonic metamaterials with outstanding chiroplasmonic properties. Despite the considerable potential of metal helicoid nanoparticles in chiroplasmonic sensing, their sensing capabilities remain elusive, stressing the need for the rational chirality engineering of helicoid nanoparticles. In this report, Au@Pd helicoid nanoparticles with engineered chiroplasmonic properties and integrated hydrogen sensing capabilities are rationally synthesized. As chiroplasmonic metamaterials, the Au@Pd helicoid nanoparticles exhibit unprecedented sensitivity for hydrogen chiroplasmonic sensing in the visible range. A significant circular dichroism red-shift as large as 206.1 nm can be achieved when they are exposed to hydrogen. Such a high sensitivity outperforms all the plasmonic hydrogen sensors in the visible range. Besides sensitivity, the chiroplasmonic sensing platform shows a good linear range of 1.5-6.0% hydrogen concentration with higher figure of merit, excellent selectivity, and good reusability. To further demonstrate its applicability, this chiroplasmonic hydrogen sensing platform is utilized to investigate hydrogen absorption and desorption kinetics on Pd. This study heralds a new paradigm for plasmonic hydrogen sensing and highlights the tremendous potential of utilizing helicoid nanoparticles as chiroplasmonic sensing metamaterials by chirality engineering.
Collapse
Affiliation(s)
- Xiali Lv
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, 230026, China
| | - Fengxia Wu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Yu Tian
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Peng Zuo
- School of Chemical Engineering and Technology, North University of China, Taiyuan, Shanxi, 030051, China
| | - Fenghua Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Guobao Xu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, 230026, China
| | - Wenxin Niu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, 230026, China
| |
Collapse
|
3
|
Ma T, Sang W, Tian J, Ma L, Ma L, Li J. Active control of circular dichroism in a graphene-metal hybridized metamaterial driven by symmetry-protected bound states in the continuum. Phys Chem Chem Phys 2023; 25:29664-29671. [PMID: 37882217 DOI: 10.1039/d3cp03288d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Active control of chirality in plasmonic metamaterials is of great importance due to their potential for diverse applications in imaging, communication and spectroscopy. Recently, inspired by the concept of bound states in the continuum (BIC), strong chiroptical responses are constructed in metamaterials by introducing structural asymmetries. However, most of these chiral metamaterials are static and cannot be modulated. Herein, we theoretically demonstrate a novel approach for manipulating chiroptical responses with enhanced circular dichroism (CD) and large modulation depths in a graphene-metal hybridized metamaterial. By introducing a structured graphene and adjusting the Fermi energy (EF), the conversion between BIC and quasi-BIC states is achieved successfully. The proposed device demonstrates a tuneable CD in the range of 0.693-0.008 when EF is adjusted from 0.01 eV to 1.0 eV, which can be further improved by optimizing its geometry. The proposed graphene-metal hybridized metamaterial paves a new way for manipulating polarization states at terahertz frequencies and is of great potential for practical applications such as dynamic display and optoelectronic modulation.
Collapse
Affiliation(s)
- Tian Ma
- School of Safety Science and Engineering, Xi'an University of Science and Technology (XUST), Xi'an 710054, China.
| | - Wei Sang
- School of Safety Science and Engineering, Xi'an University of Science and Technology (XUST), Xi'an 710054, China.
| | - Jiangkun Tian
- College of Sciences, Xi'an University of Science and Technology (XUST), Xi'an 710054, China
| | - Lingyun Ma
- School of Opto-electronical Engineering, Xi'an Technological University, Xi'an 710021, China
| | - Li Ma
- School of Safety Science and Engineering, Xi'an University of Science and Technology (XUST), Xi'an 710054, China.
| | - Jun Li
- School of Safety Science and Engineering, Xi'an University of Science and Technology (XUST), Xi'an 710054, China.
| |
Collapse
|
4
|
Tadgell B, Liz-Marzán LM. Probing Interactions between Chiral Plasmonic Nanoparticles and Biomolecules. Chemistry 2023; 29:e202301691. [PMID: 37581332 DOI: 10.1002/chem.202301691] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 08/15/2023] [Accepted: 08/15/2023] [Indexed: 08/16/2023]
Abstract
Chiral plasmonic nanoparticles (and their assemblies) interact with biomolecules in a variety of different ways, resulting in distinct optical signatures when probed by circular dichroism spectroscopy. These systems show promise for biosensing applications and offer several advantages over achiral plasmonic systems. Arguably the most notable advantage is that chiral nanoparticles can differentiate between molecular enantiomers and can, therefore, act as sensors for enantiomeric purity. Furthermore, chiral nanoparticles can couple more effectively to chiral biomolecules in biological systems if they have a matching handedness, improving their effectiveness as biomedical agents. In this article, we review the different types of interactions that occur between chiral plasmonic nanoparticle systems and biomolecules, and discuss how circular dichroism spectroscopy can probe these interactions and inform how to optimize systems for biosensing and biomedical applications.
Collapse
Affiliation(s)
- Ben Tadgell
- CIC biomaGUNE, Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, 20014, Donostia-San Sebastián, Spain
| | - Luis M Liz-Marzán
- CIC biomaGUNE, Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, 20014, Donostia-San Sebastián, Spain
- Networking Biomedical Research Center, Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Paseo de Miramón 194, 20014, Donostia-San Sebastián, Spain
- Ikerbasque, 48009, Bilbao, Spain
- Cinbio, Universidade de Vigo, Campus Universitario, 36310, Vigo, Spain
| |
Collapse
|
5
|
Chung T, Wang H, Cai H. Dielectric metasurfaces for next-generation optical biosensing: a comparison with plasmonic sensing. NANOTECHNOLOGY 2023; 34:10.1088/1361-6528/ace117. [PMID: 37352839 PMCID: PMC10416613 DOI: 10.1088/1361-6528/ace117] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 06/22/2023] [Indexed: 06/25/2023]
Abstract
In the past decades, nanophotonic biosensors have been extended from the extensively studied plasmonic platforms to dielectric metasurfaces. Instead of plasmonic resonance, dielectric metasurfaces are based on Mie resonance, and provide comparable sensitivity with superior resonance bandwidth, Q factor, and figure-of-merit. Although the plasmonic photothermal effect is beneficial in many biomedical applications, it is a fundamental limitation for biosensing. Dielectric metasurfaces solve the ohmic loss and heating problems, providing better repeatability, stability, and biocompatibility. We review the high-Q resonances based on various physical phenomena tailored by meta-atom geometric designs, and compare dielectric and plasmonic metasurfaces in refractometric, surface-enhanced, and chiral sensing for various biomedical and diagnostic applications. Departing from conventional spectral shift measurement using spectrometers, imaging-based and spectrometer-less biosensing are highlighted, including single-wavelength refractometric barcoding, surface-enhanced molecular fingerprinting, and integrated visual reporting. These unique modalities enabled by dielectric metasurfaces point to two important research directions. On the one hand, hyperspectral imaging provides massive information for smart data processing, which not only achieve better biomolecular sensing performance than conventional ensemble averaging, but also enable real-time monitoring of cellular or microbial behaviour in physiological conditions. On the other hand, a single metasurface can integrate both functions of sensing and optical output engineering, using single-wavelength or broadband light sources, which provides simple, fast, compact, and cost-effective solutions. Finally, we provide perspectives in future development on metasurface nanofabrication, functionalization, material, configuration, and integration, towards next-generation optical biosensing for ultra-sensitive, portable/wearable, lab-on-a-chip, point-of-care, multiplexed, and scalable applications.
Collapse
Affiliation(s)
- Taerin Chung
- Tech4Health Institute, New York University Langone Health, New York, NY 10016, United States of America
- Department of Radiology, New York University Langone Health, New York, NY 10016, United States of America
| | - Hao Wang
- Tech4Health Institute, New York University Langone Health, New York, NY 10016, United States of America
- Department of Radiology, New York University Langone Health, New York, NY 10016, United States of America
| | - Haogang Cai
- Tech4Health Institute, New York University Langone Health, New York, NY 10016, United States of America
- Department of Radiology, New York University Langone Health, New York, NY 10016, United States of America
- Department of Biomedical Engineering, New York University, Brooklyn, NY 11201, United States of America
| |
Collapse
|
6
|
Yang B, Huang Y, Wu B, Ma Z, Zhou K, Wu X. Enhanced chirality induced in a composite structure consisting of α-MoO 3 film and a silver metasurface. APPLIED OPTICS 2023; 62:3855-3860. [PMID: 37706694 DOI: 10.1364/ao.482782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 04/27/2023] [Indexed: 09/15/2023]
Abstract
Chiral structures have been widely used in many fields, such as biosensing and analytical chemistry. In this paper, the chiral response of a composite structure consisting of α-M o O 3 film and a silver (Ag) metasurface is studied. First, the effect of the thickness of α-M o O 3 film on the circular dichroism (CD) is discussed, and it is found that CD can reach 0.93 at a wavelength of 9.6 µm when the thickness of α-M o O 3 film is 6.075 µm. To better understand the physical mechanism, we analyze the transverse electric and transverse magnetic wave components in the transmitted wave for the whole structure and each layer. One can see that the strong chirality of the structure is attributed to the polarization conversion of α-M o O 3 film and the selective transmissivity of Ag ribbons. In addition, the influence of the filling factor of the Ag ribbons on chirality is also studied. This work combines hyperbolic material α-M o O 3 with Ag ribbons to enhance CD. Also, it provides greater freedom in the tuning of chirality. We believe that this work not only deepens the understanding of the chiral response of anisotropic materials, but also gives promise for its applications in the fields of polarization optics and biosensing.
Collapse
|
7
|
Manoccio M, Tasco V, Todisco F, Passaseo A, Cuscuna M, Tarantini I, Gigli G, Esposito M. Surface Lattice Resonances in 3D Chiral Metacrystals for Plasmonic Sensing. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2206930. [PMID: 36575146 PMCID: PMC9951338 DOI: 10.1002/advs.202206930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Indexed: 06/17/2023]
Abstract
Chiral lattice modes are hybrid states arising from the chiral plasmonic particles assembled in ordered arrays with opportune periodicity. These resonances exhibit dependence on excitation handedness, and their observation in plasmonic lattices is strictly related to the chiroptical features of the fundamental plasmonic unit. Here, the emergence of chiral surface lattice resonances (c-SLRs) is shown in properly engineered arrays of nanohelices (NHs), fully three dimensional (3D) chiral nano-objects fabricated by focused ion beam processing. By tuning the relative weight of plasmonic and photonic components in the hybrid mode, the physical mechanism of strong diffractive coupling leading to the emergence of the lattice modes is analyzed, opening the way to the engineering of chiral plasmonic systems for sensing applications. In particular, a coupling regime is identified where the combination of a large intrinsic circular dichroism (CD) of the plasmonic resonance with a well-defined balance between the photonic quality factor (Q factor) and the plasmonic field enhancement (M) maximizes the capability of the system to discriminate refractive index (RI) changes in the surrounding medium. The results lay the foundation for exploiting CD in plasmonic lattices to high performance refractometric sensing.
Collapse
Affiliation(s)
| | | | | | - Adriana Passaseo
- CNR NANOTEC Institute of NanotechnologyVia MonteroniLecce73100Italy
| | - Massimo Cuscuna
- CNR NANOTEC Institute of NanotechnologyVia MonteroniLecce73100Italy
| | - Iolena Tarantini
- Department of Mathematics and Physics Ennio De GiorgiUniversity of SalentoVia ArnesanoLecce73100Italy
| | - Giuseppe Gigli
- CNR NANOTEC Institute of NanotechnologyVia MonteroniLecce73100Italy
- Department of Mathematics and Physics Ennio De GiorgiUniversity of SalentoVia ArnesanoLecce73100Italy
| | - Marco Esposito
- CNR NANOTEC Institute of NanotechnologyVia MonteroniLecce73100Italy
| |
Collapse
|
8
|
Simone G. Trends of Biosensing: Plasmonics through Miniaturization and Quantum Sensing. Crit Rev Anal Chem 2023:1-26. [PMID: 36601882 DOI: 10.1080/10408347.2022.2161813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Despite being extremely old concepts, plasmonics and surface plasmon resonance-based biosensors have been increasingly popular in the recent two decades due to the growing interest in nanooptics and are now of relevant significance in regards to applications associated with human health. Plasmonics integration into point-of-care devices for health surveillance has enabled significant levels of sensitivity and limit of detection to be achieved and has encouraged the expansion of the fields of study and market niches devoted to the creation of quick and incredibly sensitive label-free detection. The trend reflects in wearable plasmonic sensor development as well as point-of-care applications for widespread applications, demonstrating the potential impact of the new generation of plasmonic biosensors on human well-being through the concepts of personalized medicine and global health. In this context, the aim here is to discuss the potential, limitations, and opportunities for improvement that have arisen as a result of the integration of plasmonics into microsystems and lab-on-chip over the past five years. Recent applications of plasmonic biosensors in microsystems and sensor performance are analyzed. The final analysis focuses on the integration of microfluidics and lab-on-a-chip with quantum plasmonics technology prospecting it as a promising solution for chemical and biological sensing. Here it is underlined how the research in the field of quantum plasmonic sensing for biological applications has flourished over the past decade with the aim to overcome the limits given by quantum fluctuations and noise. The significant advances in nanophotonics, plasmonics and microsystems used to create increasingly effective biosensors would continue to benefit this field if harnessed properly.
Collapse
Affiliation(s)
- Giuseppina Simone
- Chemical Engineering, University of Naples 'Federico II', Naples, Italy
| |
Collapse
|
9
|
Photonic Bandgaps of One-Dimensional Photonic Crystals Containing Anisotropic Chiral Metamaterials. PHOTONICS 2022. [DOI: 10.3390/photonics9060411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Conventional photonic bandgaps (PBGs) for linear polarization waves strongly depend on the incident angle. Usually, PBGs will shift toward short wavelengths (i.e., blue-shifted gaps) as the incident angle increases, which limits their applications. In some practices, the manipulation of PBGs for circular polarization waves is also important. Here, the manipulation of PBGs for circular polarization waves is theoretically investigated. We propose one-dimensional photonic crystals (1DPCs) containing anisotropic chiral metamaterials which exhibit hyperbolic dispersion for left circular polarization (LCP) wave and elliptical dispersion for right circular polarization (RCP) wave. Based on the phase variation compensation effect between anisotropic chiral metamaterials and dielectrics, we can design arbitrary PBGs including zero-shifted and red-shifted PBGs for LCP wave. However, the PBGs remain blue-shifted for RCP wave. Therefore, we can design a high-efficiency wide-angle polarization selector based on the chiral PBGs. Our work extends the manipulation of PBGs for circular polarization waves, which has a broad range of potential applications, including omnidirectional reflection, splitting wave and enhancing photonic spin Hall effect.
Collapse
|
10
|
Valverde A, Gordón Pidal JM, Montero-Calle A, Arévalo B, Serafín V, Calero M, Moreno-Guzmán M, López MÁ, Escarpa A, Yáñez-Sedeño P, Barderas R, Campuzano S, Pingarrón JM. Paving the way for reliable Alzheimer's disease blood diagnosis by quadruple electrochemical immunosensing. ChemElectroChem 2022. [DOI: 10.1002/celc.202200055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Alejandro Valverde
- Universidad Complutense de Madrid Facultad de Ciencias Quimicas Analytical Chemistry SPAIN
| | - José M. Gordón Pidal
- Universidad de Alcala Analytical Chemistry, Physical Chemistry and Chemical Engineering SPAIN
| | - Ana Montero-Calle
- Instituto de Salud Carlos III Chronic Disease Programme, UFIEC SPAIN
| | - Beatriz Arévalo
- Universidad Complutense de Madrid Facultad de Ciencias Quimicas Analytical Chemistry SPAIN
| | - Verónica Serafín
- Universidad Complutense de Madrid Facultad de Ciencias Quimicas Analytical Chemistry SPAIN
| | | | | | - Miguel Ángel López
- Universidad de Alcala Analytical Chemsitry, Physical Chemistry and Chemical Engineering SPAIN
| | - Alberto Escarpa
- Universidad de Alcala Analytical Chemistry, Physical Chemistry and Chemical Engineering SPAIN
| | - Paloma Yáñez-Sedeño
- Universidad Complutense de Madrid Facultad de Ciencias Quimicas Analytical Chemistry SPAIN
| | - Rodrigo Barderas
- Instituto de Salud Carlos III Chronic Disease Programme, UFIEC SPAIN
| | - Susana Campuzano
- Universidad Complutense de Madrid Facultad de Ciencias Quimicas Analytical Chemistry SPAIN
| | - José Manuel Pingarrón
- Universidad Complutense de Madrid Química Analítica Av. Complutense s/n 28040 Madrid SPAIN
| |
Collapse
|
11
|
Fang C, Chai Q, Chen Y, Xing Y, Zhou Z. The chiral coating on an achiral nanostructure by the secondary effect in focused ion beam induced deposition. NANOTECHNOLOGY 2022; 33:135301. [PMID: 34905738 DOI: 10.1088/1361-6528/ac4308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Optical metamaterials are widely used in electromagnetic wave modulation due to their sub-wavelength feature sizes. In this paper, a method to plate an achiral nanopillar array with chiral coating by the secondary effect in focused ion beam induced deposition is proposed. Guided by the pattern defined in a bitmap with variable residence time, the beam scan strategy suppresses the interaction between adjacent nanostructures. A uniform chiral coating is formed on the target nanostructure without affecting the adjacent nanostructure, under carefully selected beam parameters and the rotation angle of the sample stage. Energy dispersive x-ray spectroscopy results show that the chiral film has high purity metal, which enables the generation of localized surface plasmon resonances and causes the circular dichroism (CD) under circularly polarized light illumination. Finally, the tailorable CD spectrum of the coated array is verified by the finite difference time domain method.
Collapse
Affiliation(s)
- Chen Fang
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Department of Mechanical Engineering, Southeast University, Nanjing, People's Republic of China
| | - Qing Chai
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Department of Mechanical Engineering, Southeast University, Nanjing, People's Republic of China
| | - Ye Chen
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Department of Mechanical Engineering, Southeast University, Nanjing, People's Republic of China
| | - Yan Xing
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Department of Mechanical Engineering, Southeast University, Nanjing, People's Republic of China
| | - Zaifa Zhou
- Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing, People's Republic of China
| |
Collapse
|