Article
Chemistry, Multidisciplinary
Shi Xuan Leong, Charlynn Sher Lin Koh, Howard Yi Fan Sim, Yih Hong Lee, Xuemei Han, Gia Chuong Phan-Quang, Xing Yi Ling
Summary: The study successfully achieves direct, label-free SERS sensing of biologically important enantiomers by synergizing asymmetric nanoporous gold (NPG) nanoparticles with electrochemical-SERS. This strategy is versatile and can be readily extended to detect various enantiomers, and allows for multiplex quantification of enantiomeric ratios with excellent predictive performance. The research offers a paradigm shift in achieving label-free chiral SERS sensing of various enantiomers.
Article
Engineering, Environmental
Changmin Park, Dohyun Lim, Seung Mo Kong, Nam-Il Won, Yang Ho Na, Dongha Shin
Summary: This study develops a cost-effective and time-efficient method for detecting nanoplastics, which have received significant attention due to their potential harm to the water environment. The study introduces a substrate that exhibits Surface-enhanced Raman scattering (SERS) activity and allows for the detection of nanoplastics on the substrate using darkfield-based strategy. The technique enables point-by-point detection of single nanoplastics and has universal application in establishing a global map of nanoplastics and advancing our understanding of the environmental life cycle of plastics.
Article
Nanoscience & Nanotechnology
Eun Hye Koh, Won-Chul Lee, Yeong-Jin Choi, Joung-Il Moon, Jinah Jang, Sung-Gyu Park, Jaebum Choo, Dong-Ho Kim, Ho Sang Jung
Summary: A wearable SERS sensor has been developed for molecular sweat sensing, with the capability of measuring Raman signals without detachment from the skin. Through a multi-layer design, the sensor can absorb sweat, protect the skin, enhance signal, and has great potential for drug detection applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Spectroscopy
Xinpeng Lv, Zhe Zhang, Yue Zhao, Xiaomeng Sun, Heng Jiang, Shuwen Zhang, Xianqi Sun, Xiaohong Qiu, Yang Li
Summary: This study develops a suitable virus detection hotspot using surface-enhanced Raman scattering (SERS) by reducing sodium borohydride and aggregating silver nanoparticles. Monkeypox virus and human papillomavirus fingerprints were successfully obtained and identified in serum and artificial vaginal discharge, respectively, using the principal component analysis method. The method has a low detection limit of 100 copies/mL, good reproducibility, and signal-to-noise ratio, and can solve the SERS signal interference problem in complex biological samples, showing potential for clinical application.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Engineering, Environmental
Guangda Xu, Na Li, Ye Sun, Ce Gao, Liping Ma, Peng Song, Lixin Xia
Summary: A label-free, concise, time-efficient, ultrasensitive, and selective strategy for the determination of Fe2+ ion based on SERRS spectroscopy has been developed. The platform displayed a wide linear range with an unprecedented detection limit, offering a new universal route for practical detection in various water samples. The formation of [Fe(Bpy)(3)](2+) complexes with Fe2+ induced the aggregation of AgNPs and produced an intense Raman signal, providing a theoretical foundation for quantitative analysis of Fe2+.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Spectroscopy
Soogeun Kim, Young Jin Kim, Ayoung Bang, Wansun Kim, Samjin Choi, Hee Joo Lee
Summary: The study investigated the impact of Raman excitation wavelengths on the surface-enhanced Raman spectroscopy (SERS) for the identification of nontuberculous mycobacteria (NTM). By comparing SERS spectra with three commonly used excitation wavelengths, it was found that NTM species could be distinguished with statistical differences. Utilizing principal components-linear discriminant analysis and leave-one-out cross validation, the study achieved identification accuracies for six NTM species using aromatic amino acid biomarkers at different excitation wavelengths.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Analytical
Yuan Zhang, De-Sheng Zhan, Xiao-Ying Xu, Zhe Zhang, Mahmoud Elsayed Hafez, Yue He, Yang Li, Da-Wei Li
Summary: This study developed a SERS platform for detecting DNA methylation by modifying silver nanoparticles with zirconium ions. The use of zirconium ions enabled the opening of folded DNA molecules, allowing for the identification of subtle differences between normal and methylated DNA with single base-level sensitivity.
Article
Chemistry, Analytical
Zhe Zhang, Shen Jiang, Xiaotong Wang, Tuo Dong, Yunpeng Wang, Dan Li, Xin Gao, Zhangyi Qu, Yang Li
Summary: This study presents a novel enhanced substrate for label-free detection of respiratory viruses using surface-enhanced Raman Scattering. The method involves the use of sodium borohydride to reduce silver ions, eliminating the disorganized peak signal of traditional reducing agents. The study successfully obtained the fingerprints and concentration-dependent curves of various respiratory viruses, including SARS-CoV-2, and identified them in serum and saliva within two minutes using linear discriminant diagnostic analysis. This enhanced substrate is therefore highly valuable for the global response to the COVID-19 pandemic.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Physical
T. Schoenfeldova, H. Okur, V. Vezocnik, I. Iacovache, C. Cao, M. Dal Peraro, P. Macek, B. Zuber, S. Roke
Summary: This study demonstrates an ultrasensitive method for direct detection of protein binding to liposome membranes using high throughput second harmonic scattering (SHS). The approach allows label-free and noninvasive probing of protein-membrane interactions at sub-picomolar concentrations in 3D systems.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Analytical
Xin Liu, Alei Dang, Tiehu Li, Yiting Sun, Weibin Deng, Tung-Chun Lee, Yong Yang, Amir Zada, Boning Wang, Yuhui Liu, Shaoheng Wu, Tingkai Zhao
Summary: This article introduces a surface-enhanced Raman scattering (SERS) sensor that achieves reliable and sensitive large-scale rapid screening of target analytes. The sensor demonstrates ultralow limit of detection, outstanding sensitivity, and high stability. It also allows for the multiplexed detection of pesticide residues and the recognition of target molecules in a wide range of fields.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
Article
Engineering, Environmental
Longfei Zhang, Rongfang Zhao, Yanzhou Wu, Zhiyang Zhang, Yan Chen, Meichun Liu, Na Zhou, Yunqing Wang, Xiuli Fu, Xuming Zhuang, Jianping Wang, Lingxin Chen
Summary: In this study, a one-step synthesis method was developed to prepare silver nanoparticle substrates with ultralow SERS background using anionic ligands as stabilizing agents. The SERS substrate was successfully applied for the identification of organic pollutants and the detection of degradation intermediates. Machine learning algorithms and density functional theory calculations further improved the accuracy and reliability of identification.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Chemistry, Physical
Xiaohui Ren, Ling Yang, Yuanchao Li, Xin Li
Summary: The article introduces an effective surface molecular imprinting strategy, using silver microspheres and TiO2 nanoparticles to construct plasmonic structures, successfully preparing Ag-TiO2@MIPs with high selectivity and sensitivity. The study demonstrates that this structure performs well in sulfamethazine detection.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Analytical
Di Liu, Huimin Gao, Wenji Jiang, Su Yan, Hao Liu, Junjie Chen, Sisi Wen, Wei Zhang, Xu Wang, Bing Zhao, Wei Song
Summary: In this study, three-dimensional Ag aerogel-supported Hg single-atom catalysts were used as an efficient SERS substrate for monitoring enhanced oxidase-like reactions. The effect of Hg2+ concentrations on the SERS properties of 3D Hg/Ag aerogel networks was investigated, and an optimized addition of Hg2+ resulted in specific enhancement. The formation of Ag-supported Hg SACs was confirmed using HAADF-STEM imaging and XPS measurement, and the oxidase-like catalytic mechanism of Hg/Ag SACs was revealed using DFT. This research provides a mild synthetic strategy for fabricating Ag aerogel-supported Hg single atoms with promising prospects in various catalytic fields.
ANALYTICAL CHEMISTRY
(2023)
Article
Nanoscience & Nanotechnology
Jin Li, Fugang Liu, Chang He, Feng Shen, Jian Ye
Summary: This study reports the design and synthesis of orthogonal gap-enhanced Raman tags (O-GERTs) for accurate and reliable detection against different backgrounds. The signals in the fingerprint region were found to be easily interfered, while signals in the silent region were interference-free. O-GERTs also showed higher stability compared to conventional SERS tags.
Article
Chemistry, Physical
Siyu Wang, Ruhao Pan, Wanying He, Lianfu Li, Yang Yang, Zengfeng Du, Zhendong Luan, Xin Zhang
Summary: In this study, a new type of surface-enhanced Raman scattering insertion probe (RiP-SERS) was developed for deep-sea applications using a Coccinella septempunctata-shaped SERS substrate. The Raman spectrum of biomolecules in deep-sea cold seep vents was successfully obtained. The SERS substrate showed excellent pressure resistance and successfully collected Raman peaks of various biomolecules. This successful application of SERS technology provides a new method for deep-sea biomolecule detection and has potential applications in detecting macromolecules in complex industrial systems.
APPLIED SURFACE SCIENCE
(2023)
Article
Optics
Georgina E. Shillito, Lewis Mcmillan, Graham D. Bruce, Kishan Dholakia
Summary: The ability to identify the chemical contents of a sealed container without extracting a sample can be achieved using inverse spatially offset Raman spectroscopy (ISORS). This study explores a variant of ISORS called focus-matched ISORS and compares its relative advantages with traditional ISORS for different optical properties of the sample and container.
Article
Materials Science, Multidisciplinary
Kishan S. Menghrajani, Mingzhou Chen, Kishan Dholakia, William L. Barnes
Summary: Raman spectroscopy is a powerful technique for fingerprinting materials and molecules, but fluorescence interference is a common issue. Wavelength-modulated Raman spectroscopy can reduce fluorescence background, allowing clear recording of desired Raman signals. While studying vibrational strong coupling, advantages of the wavelength-modulated Raman approach are found, but results on strong coupling remain inconclusive, calling for further research.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Genetics & Heredity
Suliman H. Yagoub, Jeremy G. Thompson, Antony Orth, Kishan Dholakia, Brant C. Gibson, Kylie R. Dunning
Summary: This study designed and fabricated a micrometer scale device to simplify the intracytoplasmic sperm injection procedure, aiming to improve embryo production and reduce variability among operators. The device demonstrated successful embryo culture and microinjection capabilities without the need for a holding pipette, enhancing traceability and efficiency in the process.
JOURNAL OF ASSISTED REPRODUCTION AND GENETICS
(2022)
Article
Genetics & Heredity
Suliman H. Yagoub, Megan Lim, Tiffany C. Y. Tan, Darren J. X. Chow, Kishan Dholakia, Brant C. Gibson, Jeremy G. Thompson, Kylie R. Dunning
Summary: A novel photopolymerized device is presented for housing and preserving oocytes and embryos during vitrification, simplifying the procedure and improving traceability.
JOURNAL OF ASSISTED REPRODUCTION AND GENETICS
(2022)
Article
Optics
Y. Arita, G. D. Bruce, E. M. Wright, S. H. Simpson, P. Zemanek, K. Dholakia
Summary: We have demonstrated a method of all-optical sympathetic cooling of a laser-trapped microsphere to sub-Kelvin temperatures, achieved through optical binding with a feedback-cooled adjacent particle. Our study opens up possibilities for multi-particle quantum entanglement and sensing in levitated optomechanics.
Article
Optics
Tomoko Takahashi, Zonghua Liu, Thangavel Thevar, Nicholas Burns, Dhugal Lindsay, John Watson, Sumeet Mahajan, Sato Yukioka, Shuhei Tanaka, Yukiko Nagai, Balair Thornton
Summary: Researchers have developed a method that combines morphological and chemical information to accurately identify different particle types using optical measurement techniques that don't require sample preparation. By using a combined holographic imaging and Raman spectroscopy setup, they collected data from six different types of marine particles suspended in a large volume of seawater. Unsupervised feature learning was performed on the images and spectral data, and the learned features were combined to achieve better clustering results compared to using only image or spectral features. This method can be used for long-term monitoring of ocean particles without the need for sample collection, and it can be applied to different types of sensor measurements without significant modifications.
Article
Neurosciences
Ergina Vourkou, Eva D. Rouiz Ortega, Sumeet Mahajan, Amrit Mudher, Efthimios M. C. Skoulakis
Summary: Tau protein accumulation is not the main cause of memory deficits, and suppressing the expression of Tau can reverse neuroplasticity defects.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Optics
Hyeonwoo Lee, Mingyu Lee, Hyeung Joo Lee, Juwon Yoon, Kishan Dholakia, Kyunghwan Oh
Summary: In this study, a novel all-fiber Bessel-like beam generator (BBG) was proposed and experimentally demonstrated to transport a dielectric particle over a distance exceeding 2mm. This was achieved by optimizing the multimode interference (MMI) in the BBG structure to create a Bessel-like beam with a propagation invariant length (PIL) and selecting an appropriate laser wavelength to suppress thermal effects. The impact of varying the diameter of the MMI region on the PIL and the transverse intensity profile of the Bessel-like beam was analyzed. This research paves the way for fiber optic applications such as novel beam shaping, optical transport, and optical imaging.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Biochemical Research Methods
George O. Dwapanyin, Darren J. X. Chow, Tiffany C. Y. Tan, Nicolas S. Dubost, Josephine M. Morizet, Kylie R. Dunning, Kishan Dholakia
Summary: Embryo quality is a crucial factor for live birth outcomes, but a reliable diagnostic method for embryo quality is still lacking in the IVF clinic. In this study, we demonstrate that digital holographic microscopy (DHM) can rapidly and non-invasively assess the refractive index of mouse embryos, providing valuable information about their lipid content. DHM detected spatio-temporal changes in refractive index during embryo development, reflecting the accumulation of intracellular lipid, which is known to compromise embryo health. DHM may offer a promising non-invasive diagnostic method for accurately assessing embryo quality.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Biochemical Research Methods
Duanyang Xu, Konstantinos N. Bourdakos, Anna Crisford, Peter Johnson, Ibrahim Abughazaleh, Panuwat Srisamran, Richard O. C. Oreffo, Sumeet Mahajan, David J. Richardson, Lin Xu
Summary: We present an all-fiber ized 1840-nm thulium-fiber-laser source for label-free biological imaging through nonlinear microscopy. The source consists of a dissipative-soliton mode-locked seed laser and a chirped-pulse-amplification system. It utilizes short pulses generated by the mode-locked laser and pulse compression techniques to achieve high-quality imaging of biological samples.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Multidisciplinary Sciences
Gavrielle R. Untracht, Mingzhou Chen, Philip Wijesinghe, Josep Mas, Harold T. Yura, Dominik Marti, Peter E. Andersen, Kishan Dholakia
Summary: The penetration depth of optical coherence tomography (OCT) is greater than conventional microscopy, but signal reduction with depth is a challenge. This study explores the role of multiple scattering in OCT image contrast and introduces a geometry that separates the incident and collection fields, enhancing contrast at depth. Theoretical and experimental results demonstrate a significant improvement in contrast, with a ninefold enhancement observed in biological samples.
Article
Physics, Multidisciplinary
Yoshihiko Arita, Stephen H. Simpson, Graham D. Bruce, Ewan M. Wright, Pavel Zemanek, Kishan Dholakia
Summary: By studying the rotation of birefringent microspheres trapped in vacuum and set into rotation by circularly polarised light, the authors explain the stable translational motion exhibited by these spheres. They demonstrate that fast rotation reduces the effect of azimuthal spin forces, resulting in nano-scale limit cycles at reduced pressures. This research has implications for designing high-stability rotors with enhanced centripetal loads and improving cooling methods for autonomous limit cycle oscillations, potentially leading to the study of non-equilibrium quantum effects.
COMMUNICATIONS PHYSICS
(2023)
Article
Optics
Jerin Geogy George, Kishan Dholakia, Shanti Bhattacharya
Summary: In this paper, a design and generation method for sidelobe-suppressed Bessel-like beams (SSBB) is described, which enhances the contrast for light-sheet imaging by suppressing the sidelobes. The interference of two Bessel beams with slightly different wavevectors is used to achieve this sidelobe suppression. The designed phase function can be realized using a spatial light modulator to generate the SSBB.
Article
Optics
Roopam K. Gupta, Nils Hempler, Graeme P. A. Malcolm, Kishan Dholakia, Simon J. Powis
Summary: T cells of the adaptive immune system are effectively protected against pathogenic challenges. Traditional labelling methods are time-consuming and expensive, but digital holographic microscopy with deep learning proves to be a faster and more cost-effective alternative. The combination of DHM and deep learning achieves high throughput and accuracy in classifying CD4+ and CD8+ T cell subsets.
Article
Optics
Xiao-Yong Duan, Graham D. Bruce, Feng Li, Kishan Dholakia
Summary: We analytically demonstrate the existence of an asymmetric optical binding force between two identical particles. This force arises from the asymmetric forward and backward scattering due to the coupling interactions between electric and magnetic dipoles. We show the rich dynamics of this phenomenon and discuss the conditions for the emergence of the asymmetric binding force.
