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Beigmohammadi M, Khadem Sadigh M, Poursamad J. Dielectric anisotropy changes in MBBA liquid crystal doped with barium titanate by a new method. Sci Rep 2024; 14:5756. [PMID: 38459208 DOI: 10.1038/s41598-024-56219-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Accepted: 03/04/2024] [Indexed: 03/10/2024] Open
Abstract
In response to the burgeoning interest in enhancing the properties of liquid crystal composites, this research systematically explores the intricate interplay between MBBA nematic liquid crystals and ferroelectric barium titanate nanoparticles. The focus is modulating dielectric properties under temperature, frequency, and an applied electric field. Nuanced insights into temperature-dependent behavior, parallel and perpendicular component alterations, and a nonlinear correlation between nanoparticle concentration and dielectric constant are revealed. The study delves into dielectric anisotropy, indicating a reduction with increasing temperature. Structural analyses validate size reduction and crystal phase maintenance of barium titanate nanoparticles (NPs), emphasizing their impact on dielectric characteristics. Frequency-dependent investigations underscore a consistent decline in permittivity with rising frequency across nanoparticle concentrations. Application of an electric field in filling process of liquid crystal cells reveals irregular changes in dielectric constant, holding promise for tailored applications in display technologies. These comprehensive findings offer valuable insights into manipulating dielectric anisotropy properties of MBBA liquid crystal by a simple method for potential advancements in optoelectronic devices and display technologies.
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Affiliation(s)
| | - Mahsa Khadem Sadigh
- Department of Laser and Optics Engineering, University of Bonab, Bonab, Iran.
| | - Jaafar Poursamad
- Department of Laser and Optics Engineering, University of Bonab, Bonab, Iran
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2
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Kato T, Uchida J, Ishii Y, Watanabe G. Aquatic Functional Liquid Crystals: Design, Functionalization, and Molecular Simulation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306529. [PMID: 38126650 PMCID: PMC10885670 DOI: 10.1002/advs.202306529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 11/26/2023] [Indexed: 12/23/2023]
Abstract
Aquatic functional liquid crystals, which are ordered molecular assemblies that work in water environment, are described in this review. Aquatic functional liquid crystals are liquid-crystalline (LC) materials interacting water molecules or aquatic environment. They include aquatic lyotropic liquid crystals and LC based materials that have aquatic interfaces, for example, nanoporous water treatment membranes that are solids preserving LC order. They can remove ions and viruses with nano- and subnano-porous structures. Columnar, smectic, bicontinuous LC structures are used for fabrication of these 1D, 2D, 3D materials. Design and functionalization of aquatic LC sensors based on aqueous/LC interfaces are also described. The ordering transitions of liquid crystals induced by molecular recognition at the aqueous interfaces provide distinct optical responses. Molecular orientation and dynamic behavior of these aquatic functional LC materials are studied by molecular dynamics simulations. The molecular interactions of LC materials and water are key of these investigations. New insights into aquatic functional LC materials contribute to the fields of environment, healthcare, and biotechnology.
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Affiliation(s)
- Takashi Kato
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
- Research Initiative for Supra-Materials, Shinshu University, Nagano, 380-8553, Japan
| | - Junya Uchida
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Yoshiki Ishii
- Department of Data Science, School of Frontier Engineering, Kitasato University, Sagamihara, 252-0373, Japan
| | - Go Watanabe
- Department of Data Science, School of Frontier Engineering, Kitasato University, Sagamihara, 252-0373, Japan
- Kanagawa Institute of Industrial Science and Technology (KISTEC), Ebina, 243-0435, Japan
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Rouhbakhsh Z, Huang JW, Ho TY, Chen CH. Liquid crystal-based chemical sensors and biosensors: From sensing mechanisms to the variety of analytical targets. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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4
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Prefab Hollow Glass Microsphere-Based Immunosensor with Liquid Crystal Sensitization for Acute Myocardial Infarction Biomarker Detection. BIOSENSORS 2022; 12:bios12070439. [PMID: 35884242 PMCID: PMC9312929 DOI: 10.3390/bios12070439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 11/18/2022]
Abstract
Quantitative detection of cardiac troponin biomarkers in blood is an important method for clinical diagnosis of acute myocardial infarction (AMI). In this work, a whispering gallery mode (WGM) microcavity immunosensor based on a prefab hollow glass microsphere (HGMS) with liquid crystal (LC) sensitization was proposed and experimentally demonstrated for label-free cardiac troponin I-C (cTnI-C) complex detection. The proposed fiber-optic immunosensor has a simple structure; the tiny modified HGMS serves as the key sensing element and the microsample reservoir simultaneously. A sensitive LC layer with cTnI-C recognition ability was deposited on the inner wall of the HGMS microcavity. The arrangement of LC molecules is affected by the cTnI-C antigen—antibody binding in the HGMS, and the small change of the surface refractive index caused by the binding can be amplified owing to the birefringence property of LC. Using the annular waveguide of the HGMS, the WGMs were easily excited by the coupling scanning laser with a microfiber, and an all-fiber cTnI-C immunosensor can be achieved by measuring the resonant wavelength shift of the WGM spectrum. Moreover, the dynamic processes of the cTnI-C antigen—antibody binding and unbinding was revealed by monitoring the wavelength shift continuously. The proposed immunosensor with a spherical microcavity can be a cost-effective tool for AMI diagnosis.
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Nguyen DK, Jang CH. Simple and Label-Free Detection of Carboxylesterase and Its Inhibitors Using a Liquid Crystal Droplet Sensing Platform. MICROMACHINES 2022; 13:mi13030490. [PMID: 35334782 PMCID: PMC8954150 DOI: 10.3390/mi13030490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 12/26/2022]
Abstract
In this study, we developed a liquid crystal (LC) droplet-based sensing platform for the detection of carboxylesterase (CES) and its inhibitors. The LC droplet patterns in contact with myristoylcholine chloride (Myr) exhibited dark cross appearances, corresponding to homeotropic anchoring of the LCs at the aqueous/LC interface. However, in the presence of CES, Myr was hydrolyzed; therefore, the optical images of the LC patterns changed to bright fan-shaped textures, corresponding to a planar orientation of LCs at the interface. In contrast, the presence of CES inhibitors, such as benzil, inhibits the hydrolysis of Myr; as a result, the LC patterns exhibit dark cross textures. This principle led to the development of an LC droplet-based sensing method with a detection limit of 2.8 U/L and 10 μM, for CES detection and its inhibitor, respectively. The developed biosensor not only enables simple and label-free detection of CES but also shows high promise for the detection of CES inhibitors.
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Hui L, Wang D, Liu Z, Zhao Y, Ji Z, Zhang M, Zhu HH, Luo W, Cheng X, Gui L, Gao W. The Cell-Isolation Capsules with Rod-Like Channels Ensure the Survival and Response of Cancer Cells to Their Microenvironment. Adv Healthc Mater 2022; 11:e2101723. [PMID: 34699694 DOI: 10.1002/adhm.202101723] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/18/2021] [Indexed: 12/16/2022]
Abstract
Current macrocapsules with semipermeable but immunoprotective polymeric membranes are attractive devices to achieve the purpose of immunoisolation, however, their ability to allow diffusion of essential nutrients and oxygen is limited, which leads to a low survival rate of encapsulated cells. Here, a novel method is reported by taking advantage of thermotropic liquid crystals, sodium laurylsulfonate (SDS) liquid crystals (LCs), and rod-like crystal fragments (LCFs) to develop engineered alginate hydrogels with rod-like channels. This cell-isolation capsule with an engineered alginate hydrogel-wall allows small molecules, large molecules, and bacteria to diffuse out from the capsules freely but immobilizes the encapsulated cells inside and prevents cells in the microenvironment from moving in. The encapsulated cells show a high survival rate with isolation of host immune cells and long-term growth with adequate nutrients and oxygen supply. In addition, by sharing and responding to the normal molecular and vesicular microenvironment (NMV microenvironment), encapsulated cancer cells display a transition from tumorous phenotypes to ductal features of normal epithelial cells. Thus, this device will be potentially useful for clinical application in cell therapy by secreting molecules and for establishment of patient-derived xenograft (PDX) models that are often difficult to achieve for certain types of tumors, such as prostate cancer.
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Affiliation(s)
- Lanlan Hui
- State Key Laboratory of Oncogenes and Related Genes Renji‐Med‐X Stem Cell Research Center Ren Ji Hospital School of Medicine and School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200127 China
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
| | - Deng Wang
- State Key Laboratory of Oncogenes and Related Genes Renji‐Med‐X Stem Cell Research Center Ren Ji Hospital School of Medicine and School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200127 China
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
| | - Zhao Liu
- Ping An Life Insurance of China, Ltd Shanghai 200120 China
| | - Yueqi Zhao
- Department of Orthopaedic Surgery Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China
| | - Zhongzhong Ji
- Shanghai Cancer Institute Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200017 China
| | - Man Zhang
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
| | - Helen He Zhu
- State Key Laboratory of Oncogenes and Related Genes Renji‐Med‐X Stem Cell Research Center Department of Urology Ren Ji Hospital School of Medicine and School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200127 China
| | - Wenqing Luo
- State Key Laboratory of Oncogenes and Related Genes Renji‐Med‐X Stem Cell Research Center Ren Ji Hospital School of Medicine and School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200127 China
| | - Xiaomu Cheng
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
| | - Liming Gui
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
| | - Wei‐Qiang Gao
- State Key Laboratory of Oncogenes and Related Genes Renji‐Med‐X Stem Cell Research Center Ren Ji Hospital School of Medicine and School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200127 China
- Med‐X Research Institute Shanghai Jiao Tong University Shanghai 200030 China
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Devi M, Verma I, Pal SK. Distinct interfacial ordering of liquid crystals observed by protein-lipid interactions that enabled the label-free sensing of cytoplasmic protein at the liquid crystal-aqueous interface. Analyst 2021; 146:7152-7159. [PMID: 34734590 DOI: 10.1039/d1an01444g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Interfaces formed between a lipid decorated liquid crystal (LC) film and an aqueous phase can mimic the bimolecular membrane where interfacially occurring biological phenomena (e.g., lipid-protein interactions, protein adsorption) can be visually monitored by observing the surface-sensitive orientations of LCs. The ordering behavior of LCs at different phospholipid-based LC interfaces (1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) and lysophosphatidic acid (LPA)) were investigated to determine the sensing of an important cytoplasmic protein (juxtamembrane of epidermal growth factor receptor (JM-EGFR)). At both DLPC and LPA decorated interfaces, the LC adopts homeotropic ordering, causing a dark optical appearance under crossed polarizers. Interestingly, upon the introduction of JM-EGFR to these LC-aqueous interfaces, the homeotropic orientation of the LC changed to planar (bright optical appearance), suggesting the potential of the designed system for JM-EGFR sensing. The use of different lipid decorated LC-aqueous interfaces results in the emergence of distinct optical patterns. For example, at a DLPC laden interface, elongated bright domains are observed, whereas a uniform bright texture is observed on an LPA laden interface. The DLPC decorated LC-aqueous interface is found to be highly selective for the sensing of JM-EGFR with a detection limit in the nanomolar concentration region (∼ 50 nM). When compared to spectroscopic and other conventional techniques, the LC-based design is simpler, and it allows the simple and label-free optical sensing of JM-EGFR at fluidic interfaces.
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Affiliation(s)
- Manisha Devi
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali (IISERM), Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Indu Verma
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali (IISERM), Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Santanu Kumar Pal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali (IISERM), Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
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Khan M, Liu S, Qi L, Ma C, Munir S, Yu L, Hu Q. Liquid crystal-based sensors for the detection of biomarkers at the aqueous/LC interface. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116434] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Fong B. Self-Cognizant Bionic Liquid Sensor for Pathogen Diagnosis. CYBORG AND BIONIC SYSTEMS 2021; 2021:9861513. [PMID: 36285143 PMCID: PMC9494726 DOI: 10.34133/2021/9861513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 08/26/2021] [Indexed: 01/26/2023] Open
Abstract
As observed in the outbreaks of SARS and swine flu, as well as many other infectious diseases, the huge volume of human traffic across numerous enclosed public venues has posed immense challenges to preventing the spread of communicable diseases. There is an urgent need for effective disease surveillance management in public areas under pandemic outbreaks. The physicochemical properties associated with ionic liquids make them particularly suited for molecular communications in sensing networks where low throughput is quite adequate for pathogen detection. This paper presents a self-cognizant system for rapid diagnosis of infectious disease using a bionic sensor such that testing can be supported without collecting a fluid sample from a subject through any invasive methods. The system is implemented for testing the performance of the proposed bionic liquid sensing network.
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Affiliation(s)
- B. Fong
- Providence University, Taiwan (Province of China)
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10
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Liquid crystal-based biosensors as lab-on-chip tools: Promising for future on-site detection test kits. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116325] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Isik B, Cakar F, Cankurtaran O, Cankurtaran H. Liquid Crystal Entrapped Porous Films for Ammonia Sensing and Determination of Surface Properties of Liquid Crystal Molecule. ChemistrySelect 2021. [DOI: 10.1002/slct.202100638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Birol Isik
- Department of Chemistry Yildiz Technical University Faculty of Arts & Sciences Davutpasa Campus Esenler 34220 Istanbul Turkey
| | - Fatih Cakar
- Department of Chemistry Yildiz Technical University Faculty of Arts & Sciences Davutpasa Campus Esenler 34220 Istanbul Turkey
| | - Ozlem Cankurtaran
- Department of Chemistry Yildiz Technical University Faculty of Arts & Sciences Davutpasa Campus Esenler 34220 Istanbul Turkey
| | - Husnu Cankurtaran
- Department of Chemistry Yildiz Technical University Faculty of Arts & Sciences Davutpasa Campus Esenler 34220 Istanbul Turkey
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Optical Gas Sensing with Liquid Crystal Droplets and Convolutional Neural Networks. SENSORS 2021; 21:s21082854. [PMID: 33919620 PMCID: PMC8073403 DOI: 10.3390/s21082854] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/13/2021] [Accepted: 04/14/2021] [Indexed: 01/14/2023]
Abstract
Liquid crystal (LC)-based materials are promising platforms to develop rapid, miniaturised and low-cost gas sensor devices. In hybrid gel films containing LC droplets, characteristic optical texture variations are observed due to orientational transitions of LC molecules in the presence of distinct volatile organic compounds (VOC). Here, we investigate the use of deep convolutional neural networks (CNN) as pattern recognition systems to analyse optical textures dynamics in LC droplets exposed to a set of different VOCs. LC droplets responses to VOCs were video recorded under polarised optical microscopy (POM). CNNs were then used to extract features from the responses and, in separate tasks, to recognise and quantify the vapours exposed to the films. The impact of droplet diameter on the results was also analysed. With our classification models, we show that a single individual droplet can recognise 11 VOCs with small structural and functional differences (F1-score above 93%). The optical texture variation pattern of a droplet also reflects VOC concentration changes, as suggested by applying a regression model to acetone at 0.9-4.0% (v/v) (mean absolute errors below 0.25% (v/v)). The CNN-based methodology is thus a promising approach for VOC sensing using responses from individual LC-droplets.
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Nguyen DK, Jang CH. A Label-Free Liquid Crystal Biosensor Based on Specific DNA Aptamer Probes for Sensitive Detection of Amoxicillin Antibiotic. MICROMACHINES 2021; 12:mi12040370. [PMID: 33808299 PMCID: PMC8065461 DOI: 10.3390/mi12040370] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 12/19/2022]
Abstract
We developed a liquid crystal (LC) aptamer biosensor for the sensitive detection of amoxicillin (AMX). The AMX aptamer was immobilized onto the surface of a glass slide modified with a mixed self-assembled layer of dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DMOAP) and (3-aminopropyl) triethoxysilane (APTES). The long alkyl chains of DMOAP maintained the LC molecules in a homeotropic orientation and induced a dark optical appearance under a polarized light microscope (POM). In the presence of AMX, the specific binding of the aptamer and AMX molecules induced a conformational change in the aptamers, leading to the disruption of the homeotropic orientation of LCs, resulting in a bright optical appearance. The developed aptasensor showed high specificity and a low detection limit of 3.5 nM. Moreover, the potential application of the developed aptasensor for the detection of AMX in environmental samples was also demonstrated. Therefore, the proposed aptasensor is a promising platform for simple, rapid, and label-free monitoring of AMX in an actual water environment with high selectivity and sensitivity.
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A Cationic Surfactant-Decorated Liquid Crystal-Based Aptasensor for Label-Free Detection of Malathion Pesticides in Environmental Samples. BIOSENSORS-BASEL 2021; 11:bios11030092. [PMID: 33806721 PMCID: PMC8004806 DOI: 10.3390/bios11030092] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 11/25/2022]
Abstract
We report a liquid crystal (LC)-based aptasensor for the detection of malathion using a cationic surfactant-decorated LC interface. In this method, LCs displayed dark optical images when in contact with aqueous cetyltrimethylammonium bromide (CTAB) solution due to the formation of a self-assembled CTAB monolayer at the aqueous/LC interface, which induced the homeotropic orientation of LCs. With the addition of malathion aptamer, the homeotropic orientation of LCs changed to a planar one due to the interactions between CTAB and the aptamer, resulting in a bright optical image. In the presence of malathion, the formation of aptamer-malathion complexes caused a conformational change of the aptamers, thereby weakening the interactions between CTAB and the aptamers. Therefore, CTAB is free to induce a homeotropic ordering of the LCs, which corresponds to a dark optical image. The developed sensor exhibited high specificity for malathion determination and a low detection limit of 0.465 nM was achieved. Moreover, the proposed biosensor was successfully applied to detect malathion in tap water, river water, and apple samples. The proposed LC-based aptasensor is a simple, rapid, and convenient platform for label-free monitoring of malathion in environmental samples.
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Prommapan P, Brljak N, Lowry TW, Van Winkle D, Lenhert S. Aptamer Functionalized Lipid Multilayer Gratings for Label-Free Analyte Detection. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:nano10122433. [PMID: 33291389 PMCID: PMC7762078 DOI: 10.3390/nano10122433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/24/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
Lipid multilayer gratings are promising optical biosensor elements that are capable of transducing analyte binding events into changes in an optical signal. Unlike solid state transducers, reagents related to molecular recognition and signal amplification can be incorporated into the lipid grating ink volume prior to fabrication. Here we describe a strategy for functionalizing lipid multilayer gratings with a DNA aptamer for the protein thrombin that allows label-free analyte detection. A double cholesterol-tagged, double-stranded DNA linker was used to attach the aptamer to the lipid gratings. This approach was found to be sufficient for binding fluorescently labeled thrombin to lipid multilayers with micrometer-scale thickness. In order to achieve label-free detection with the sub-100 nm-thick lipid multilayer grating lines, the binding affinity was improved by varying the lipid composition. A colorimetric image analysis of the light diffracted from the gratings using a color camera was then used to identify the grating nanostructures that lead to an optimal signal. Lipid composition and multilayer thickness were found to be critical parameters for the signal transduction from the aptamer functionalized lipid multilayer gratings.
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Affiliation(s)
- Plengchart Prommapan
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA; (P.P.); (T.W.L.); (D.V.W.)
| | - Nermina Brljak
- Department of Chemistry, Florida State University, Tallahassee, FL 32306, USA;
| | - Troy W. Lowry
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA; (P.P.); (T.W.L.); (D.V.W.)
- Department of Biological Science and Integrative Nanoscience Institute, Florida State University, 77 Chieftan Way, Tallahassee, FL 32306, USA
| | - David Van Winkle
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA; (P.P.); (T.W.L.); (D.V.W.)
| | - Steven Lenhert
- Department of Biological Science and Integrative Nanoscience Institute, Florida State University, 77 Chieftan Way, Tallahassee, FL 32306, USA
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Khoshbin Z, Housaindokht MR, Izadyar M, Bozorgmehr MR, Verdian A. Recent advances in computational methods for biosensor design. Biotechnol Bioeng 2020; 118:555-578. [PMID: 33135778 DOI: 10.1002/bit.27618] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 09/25/2020] [Accepted: 10/29/2020] [Indexed: 01/20/2023]
Abstract
Biosensors are analytical tools with a great application in healthcare, food quality control, and environmental monitoring. They are of considerable interest to be designed by using cost-effective and efficient approaches. Designing biosensors with improved functionality or application in new target detection has been converted to a fast-growing field of biomedicine and biotechnology branches. Experimental efforts have led to valuable successes in the field of biosensor design; however, some deficiencies restrict their utilization for this purpose. Computational design of biosensors is introduced as a promising key to eliminate the gap. A set of reliable structure prediction of the biosensor segments, their stability, and accurate descriptors of molecular interactions are required to computationally design biosensors. In this review, we provide a comprehensive insight into the progress of computational methods to guide the design and development of biosensors, including molecular dynamics simulation, quantum mechanics calculations, molecular docking, virtual screening, and a combination of them as the hybrid methodologies. By relying on the recent advances in the computational methods, an opportunity emerged for them to be complementary or an alternative to the experimental methods in the field of biosensor design.
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Affiliation(s)
- Zahra Khoshbin
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Mohammad Izadyar
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Asma Verdian
- Department of Food Safety and Quality Control, Research Institute of Food Science and Technology (RIFST), Mashhad, Iran
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18
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Esteves C, Ramou E, Porteira ARP, Barbosa AJM, Roque ACA. Seeing the Unseen: The Role of Liquid Crystals in Gas-Sensing Technologies. ADVANCED OPTICAL MATERIALS 2020; 8:1902117. [PMID: 32612901 PMCID: PMC7329384 DOI: 10.1002/adom.201902117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 02/17/2020] [Indexed: 05/17/2023]
Abstract
Fast, real-time detection of gases and volatile organic compounds (VOCs) is an emerging research field relevant to most aspects of modern society, from households to health facilities, industrial units, and military environments. Sensor features such as high sensitivity, selectivity, fast response, and low energy consumption are essential. Liquid crystal (LC)-based sensors fulfill these requirements due to their chemical diversity, inherent self-assembly potential, and reversible molecular order, resulting in tunable stimuliresponsive soft materials. Sensing platforms utilizing thermotropic uniaxial systems-nematic and smectic-that exploit not only interfacial phenomena, but also changes in the LC bulk, are demonstrated. Special focus is given to the different interaction mechanisms and tuned selectivity toward gas and VOC analytes. Furthermore, the different experimental methods used to transduce the presence of chemical analytes into macroscopic signals are discussed and detailed examples are provided. Future perspectives and trends in the field, in particular the opportunities for LC-based advanced materials in artificial olfaction, are also discussed.
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Affiliation(s)
- Carina Esteves
- UCIBIO, Departamento de Química Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica 2829-516, Portugal
| | - Efthymia Ramou
- UCIBIO, Departamento de Química Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica 2829-516, Portugal
| | - Ana Raquel Pina Porteira
- UCIBIO, Departamento de Química Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica 2829-516, Portugal
| | - Arménio Jorge Moura Barbosa
- UCIBIO, Departamento de Química Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica 2829-516, Portugal
| | - Ana Cecília Afonso Roque
- UCIBIO, Departamento de Química Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica 2829-516, Portugal
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Ho T, Lan YH, Huang JW, Chang JJ, Chen CH. Using Diazotization Reaction to Develop Portable Liquid-Crystal-Based Sensors for Nitrite Detection. ACS OMEGA 2020; 5:11809-11816. [PMID: 32478272 PMCID: PMC7254784 DOI: 10.1021/acsomega.0c01233] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 04/29/2020] [Indexed: 05/14/2023]
Abstract
A liquid-crystal (LC)-based sensor for detecting nitrite in aqueous solutions was developed using a diazotization reaction as the sensing mechanism. First, tetradecyl 4-aminobenzoate (14CBA) was synthesized and doped into a nematic LC, i.e., 4-cyano-4'-pentylbiphenyl (5CB). When the LC mixture was cast on a glass substrate and then immersed into an aqueous solution without nitrite, the orientation of LC was planar and the LC image was bright. In the presence of nitrite, it reacted with alkylanilines to give corresponding diazonium ions with a positive charge, which aligned at the LC/aqueous interface to cause homeotropic orientation of LC. As a result, a bright-to-dark transition of the LC image was observed. The limit of detection (LOD) of this system for nitrite is 25 μM with high selectivity. In addition, this system can work in environmental water samples such as tap water and pond water. Finally, we demonstrated that the optical signals of LC can be measured and recorded using a built-in digital camera of a smartphone, suggesting the portability of this system for on-site applications.
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Xia C, Zhou D, Su Y, Zhou G, Yao L, Sun W, Liu Y. A liquid-crystal-based immunosensor for the detection of cardiac troponin I. Analyst 2020; 145:4569-4575. [DOI: 10.1039/d0an00425a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cardiac troponin I (cTnI) is one of the most sensitive and specific markers of myocardial cell injury. In this study, a label-free biosensor that utilizes the birefringence property of liquid crystal (LC) for the detection of cTnI is demonstrated.
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Affiliation(s)
- Chunli Xia
- Key Lab of In-fiber Integrated Optics
- Ministry Education of China
- Harbin Engineering University
- Harbin 150001
- China
| | - Dong Zhou
- Key Lab of In-fiber Integrated Optics
- Ministry Education of China
- Harbin Engineering University
- Harbin 150001
- China
| | - Yueming Su
- Key Lab of In-fiber Integrated Optics
- Ministry Education of China
- Harbin Engineering University
- Harbin 150001
- China
| | - Guangkai Zhou
- Department of head and neck surgery
- Affiliated Tumor Hospital of Harbin Medical University
- Harbin 150001
- China
| | - Lishuang Yao
- State Key Laboratory of Applied Optics
- Changchun Institute of Optics
- Fine Mechanics and Physics
- Chinese Academy of Sciences
- Changchun 130033
| | - Weimin Sun
- Key Lab of In-fiber Integrated Optics
- Ministry Education of China
- Harbin Engineering University
- Harbin 150001
- China
| | - Yongjun Liu
- Key Lab of In-fiber Integrated Optics
- Ministry Education of China
- Harbin Engineering University
- Harbin 150001
- China
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21
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Clemente APB, Kuang H, Shabana AM, Labuza TP, Kokkoli E. Design of an Aptamer-Amphiphile for the Detection of β-Lactoglobulin on a Liquid Crystal Interface. Bioconjug Chem 2019; 30:2763-2770. [PMID: 31589417 DOI: 10.1021/acs.bioconjchem.9b00412] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An aptamer-amphiphile was designed that binds to β-lactoglobulin (β-LG), a major allergen from cow's milk. For this work, a 23-nucleotide ssDNA aptamer β-LG-23, capable of forming antiparallel G-quadruplexes was used, and its specificity and binding affinity of 22 ± 2 nM for β-LG were evaluated via enzyme-linked apta-sorbent assay (ELASA). The β-LG-23 aptamer was synthesized as an amphiphile by conjugating it to a C16 double tail via different spacers, and the effect of the spacers on the binding affinity and secondary structure of the aptamer was investigated. From all amphiphiles tested, direct conjugation of the aptamer to the tail gave the lowest binding affinity to β-LG (37 ± 2 nM), while maintaining the antiparallel G-quadruplex secondary structure of the aptamer. As a proof of concept, the β-LG-23 aptamer-amphiphile was used to decorate the interface of a liquid crystal (LC) and effectively detected 10 nM or 0.18 ppm of β-LG with a 20 min equilibration time, thus demonstrating that it has the potential to be used for fast and label-free detection of β-LG.
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Affiliation(s)
- Ana Paula Brumann Clemente
- Department of Food Science and Nutrition , University of Minnesota , St. Paul , Minnesota 55108 , United States
| | - Huihui Kuang
- Institute for NanoBioTechnology , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Ahmed M Shabana
- Institute for NanoBioTechnology , Johns Hopkins University , Baltimore , Maryland 21218 , United States.,Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy , Cairo University , Cairo 11562 , Egypt
| | - Theodore P Labuza
- Department of Food Science and Nutrition , University of Minnesota , St. Paul , Minnesota 55108 , United States
| | - Efrosini Kokkoli
- Institute for NanoBioTechnology , Johns Hopkins University , Baltimore , Maryland 21218 , United States.,Department of Chemical and Biomolecular Engineering , Johns Hopkins University , Baltimore , Maryland 21218 , United States
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22
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Vallamkondu J, Corgiat EB, Buchaiah G, Kandimalla R, Reddy PH. Liquid Crystals: A Novel Approach for Cancer Detection and Treatment. Cancers (Basel) 2018; 10:E462. [PMID: 30469457 PMCID: PMC6267481 DOI: 10.3390/cancers10110462] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/02/2018] [Accepted: 11/05/2018] [Indexed: 11/23/2022] Open
Abstract
Liquid crystals are defined as the fourth state of matter forming between solid and liquid states. Earlier the applications of liquid crystals were confined to electronic instruments, but recent research findings suggest multiple applications of liquid crystals in biology and medicine. Here, the purpose of this review article is to discuss the potential biological impacts of liquid crystals in the diagnosis and prognosis of cancer along with the risk assessment. In this review, we also discussed the recent advances of liquid crystals in cancer biomarker detection and treatment in multiple cell line models. Cases reviewed here will demonstrate that cancer diagnostics based on the multidisciplinary technology and intriguingly utilization of liquid crystals may become an alternative to regular cancer detection methodologies. Additionally, we discussed the formidable challenges and problems in applying liquid crystal technologies. Solving these problems will require great effort and the way forward is through the multidisciplinary collaboration of physicists, biologists, chemists, material-scientists, clinicians, and engineers. The triumphant outcome of these liquid crystals and their applications in cancer research would be convenient testing for the detection of cancer and may result in treating the cancer patients non-invasively.
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Affiliation(s)
- Jayalakshmi Vallamkondu
- Department of Physics, NIT Warangal, Telangana 506004, India.
- Centre for Advanced Materials, NIT Warangal, Telangana 506004, India.
| | - Edwin Bernard Corgiat
- Department of Cellular Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | | | - Ramesh Kandimalla
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Neurology Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
| | - P Hemachandra Reddy
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Neurology Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Pharmacology and Neuroscience Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, 6630 S. Quaker Suite E, MS 7495, Lubbock, TX 79413, USA.
- Cell Biology and Biochemistry Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Speech, Language and Hearing Sciences Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
- Department of Public Health, Graduate School of Biomedical Sciences, 3601 4th Street, MS 9424, Lubbock, TX 79430, USA.
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23
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Kim HJ, Jang CH. Imaging DNA single-strand breaks generated by reactive oxygen species using a liquid crystal-based sensor. Anal Biochem 2018; 556:1-6. [DOI: 10.1016/j.ab.2018.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 06/05/2018] [Accepted: 06/12/2018] [Indexed: 11/17/2022]
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24
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Yildirim A, Szymoniak P, Sentker K, Butschies M, Bühlmeyer A, Huber P, Laschat S, Schönhals A. Dynamics and ionic conductivity of ionic liquid crystals forming a hexagonal columnar mesophase. Phys Chem Chem Phys 2018; 20:5626-5635. [DOI: 10.1039/c7cp08186c] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time, the molecular mobility of two linear-shaped tetramethylated guanidinium triflate ionic liquid crystals (ILCs) having different lengths of alkyl chains was investigated using a combination of broadband dielectric (BDS) and specific heat spectroscopy (SHS).
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Affiliation(s)
- Arda Yildirim
- Bundesanstalt für Materialforschung und -prüfung (BAM)
- Unter den Eichen 87
- 12205 Berlin
- Germany
| | - Paulina Szymoniak
- Bundesanstalt für Materialforschung und -prüfung (BAM)
- Unter den Eichen 87
- 12205 Berlin
- Germany
| | - Kathrin Sentker
- Institut für Materialphysik und -Technologie
- Technische Universität Hamburg
- Eißendorfer Str. 42
- 21073 Hamburg
- Germany
| | - Martin Butschies
- Institut für Organische Chemie
- Universität Stuttgart
- Pfaffenwaldring 55
- 70569 Stuttgart
- Germany
| | - Andrea Bühlmeyer
- Institut für Organische Chemie
- Universität Stuttgart
- Pfaffenwaldring 55
- 70569 Stuttgart
- Germany
| | - Patrick Huber
- Institut für Materialphysik und -Technologie
- Technische Universität Hamburg
- Eißendorfer Str. 42
- 21073 Hamburg
- Germany
| | - Sabine Laschat
- Institut für Organische Chemie
- Universität Stuttgart
- Pfaffenwaldring 55
- 70569 Stuttgart
- Germany
| | - Andreas Schönhals
- Bundesanstalt für Materialforschung und -prüfung (BAM)
- Unter den Eichen 87
- 12205 Berlin
- Germany
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25
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Hussain A, Semeano ATS, Palma SICJ, Pina AS, Almeida J, Medrado BF, Pádua ACCS, Carvalho AL, Dionísio M, Li RWC, Gamboa H, Ulijn RV, Gruber J, Roque ACA. Tunable Gas Sensing Gels by Cooperative Assembly. ADVANCED FUNCTIONAL MATERIALS 2017; 27:1700803. [PMID: 28747856 PMCID: PMC5524183 DOI: 10.1002/adfm.201700803] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The cooperative assembly of biopolymers and small molecules can yield functional materials with precisely tunable properties. Here, the fabrication, characterization, and use of multicomponent hybrid gels as selective gas sensors are reported. The gels are composed of liquid crystal droplets self-assembled in the presence of ionic liquids, which further coassemble with biopolymers to form stable matrices. Each individual component can be varied and acts cooperatively to tune gels' structure and function. The unique molecular environment in hybrid gels is explored for supramolecular recognition of volatile compounds. Gels with distinct compositions are used as optical and electrical gas sensors, yielding a combinatorial response conceptually mimicking olfactory biological systems, and tested to distinguish volatile organic compounds and to quantify ethanol in automotive fuel. The gel response is rapid, reversible, and reproducible. These robust, versatile, modular, pliant electro-optical soft materials possess new possibilities in sensing triggered by chemical and physical stimuli.
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Affiliation(s)
- Abid Hussain
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Ana T. S. Semeano
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal; Departamento de Química Fundamental, Instituto de Química da Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 CEP 05508-000, São Paulo, SP, Brasil
| | - Susana I. C. J. Palma
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Ana S. Pina
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal; Advanced Science Research Center (ASRC), City University of New York, New York 10031, USA
| | - José Almeida
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Bárbara F. Medrado
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal; Departamento de Química Fundamental, Instituto de Química da Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 CEP 05508-000, São Paulo, SP, Brasil
| | - Ana C. C. S. Pádua
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Ana L. Carvalho
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Madalena Dionísio
- LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Rosamaria W. C. Li
- Departamento de Química Fundamental, Instituto de Química da Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 CEP 05508-000, São Paulo, SP, Brasil; Centro Universitário Estácio Radial de São Paulo, Vila dos Remédios, CEP 05107-001 São Paulo, SP, Brasil
| | - Hugo Gamboa
- Laboratório de Instrumentação, Engenharia Biomédica e Física da Radiação (LIBPhys-UNL), Departamento de Física, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Monte da Caparica, 2892-516 Caparica, Portugal
| | - Rein V. Ulijn
- Advanced Science Research Center (ASRC), City University of New York, New York 10031, USA; Hunter College, Department of Chemistry and Biochemistry, 695 Park Avenue, New York, NY 10065, USA; PhD Programs in Chemistry and Biochemistry, The Graduate Center of the City University of New York, New York, NY 10016, USA
| | - Jonas Gruber
- Departamento de Química Fundamental, Instituto de Química da Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 CEP 05508-000, São Paulo, SP, Brasil
| | - Ana C. A. Roque
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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26
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Niu X, Zhong Y, Chen R, Wang F, Luo D. Highly sensitive and selective liquid crystal optical sensor for detection of ammonia. OPTICS EXPRESS 2017; 25:13549-13556. [PMID: 28788898 DOI: 10.1364/oe.25.013549] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 05/31/2017] [Indexed: 06/07/2023]
Abstract
Ammonia detection technologies are very important in environment monitoring. However, most existing technologies are complex and expensive, which limit the useful range of real-time application. Here, we propose a highly sensitive and selective optical sensor for detection of ammonia (NH3) based on liquid crystals (LCs). This optical sensor is realized through the competitive binding between ammonia and liquid crystals on chitosan-Cu2+ that decorated on glass substrate. We achieve a broad detection range of ammonia from 50 ppm to 1250 ppm, with a low detection limit of 16.6 ppm. This sensor is low-cost, simple, fast, and highly sensitive and selective for detection of ammonia. The proposal LC sensing method can be a sensitive detection platform for other molecule monitors such as proteins, DNAs and other heavy metal ions by modifying sensing molecules.
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27
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Liu Q, Zuo F, Zhao Z, Chen J, Xu D. Molecular dynamics investigations of an indicator displacement assay mechanism in a liquid crystal sensor. Phys Chem Chem Phys 2017; 19:23924-23933. [DOI: 10.1039/c7cp02292a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Molecular dynamic simulations were applied to address the binding competition mechanism in an IDA based LC sensor system.
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Affiliation(s)
- Qingyu Liu
- College of Chemistry and Environment Protection Engineering
- SouthWest University for Nationalities
- Chengdu
- P. R. China
| | - Fang Zuo
- College of Chemistry and Environment Protection Engineering
- SouthWest University for Nationalities
- Chengdu
- P. R. China
| | - Zhigang Zhao
- College of Chemistry and Environment Protection Engineering
- SouthWest University for Nationalities
- Chengdu
- P. R. China
| | - Junxian Chen
- College of Chemistry and Environment Protection Engineering
- SouthWest University for Nationalities
- Chengdu
- P. R. China
| | - Dingguo Xu
- MOE Key Laboratory of Green Chemistry and Technology
- College of Chemistry
- Sichuan University
- P. R. China
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28
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Popov P, Mann EK, Jákli A. Thermotropic liquid crystal films for biosensors and beyond. J Mater Chem B 2017; 5:5061-5078. [DOI: 10.1039/c7tb00809k] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent results on structural properties and possible bio-sensing applications of planar liquid crystal films are reviewed.
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Affiliation(s)
- Piotr Popov
- Department of Physics
- Kent State University
- Kent
- USA
- Liquid Crystal Institute
| | | | - Antal Jákli
- Liquid Crystal Institute
- Kent State University
- Kent
- USA
- Complex Fluid Group
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29
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Affiliation(s)
- Alinaghi Salari
- Department of Chemical Engineering; University of Toronto; 200 College Street Toronto Ontario M5S 3E5 Canada
| | - Eugenia Kumacheva
- Department of Chemical Engineering; University of Toronto; 200 College Street Toronto Ontario M5S 3E5 Canada
- Department of Chemistry; University of Toronto; 80 Saint George Street Toronto Ontario M5S 3H6 Canada
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; 164 College Street Toronto Ontario M5S 3G9 Canada
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30
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Alama S, Bronsard L, Lamy X. Analytical description of the Saturn-ring defect in nematic colloids. Phys Rev E 2016; 93:012705. [PMID: 26871133 DOI: 10.1103/physreve.93.012705] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Indexed: 06/05/2023]
Abstract
We derive an analytical formula for the Saturn-ring configuration around a small colloidal particle suspended in nematic liquid crystal. In particular we obtain an explicit expression for the ring radius and its dependence on the anchoring energy. We work within Landau-de Gennes theory: Nematic alignment is described by a tensorial order parameter. For nematic colloids this model had previously been used exclusively to perform numerical computations. Our method demonstrates that the tensorial theory can also be used to obtain analytical results, suggesting a different approach to the understanding of nematic colloidal interactions.
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Affiliation(s)
- Stan Alama
- Department of Mathematics and Statistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4K1
| | - Lia Bronsard
- Department of Mathematics and Statistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4K1
| | - Xavier Lamy
- Institut Camille Jordan, Université Lyon 1, 43 Boulevard du 11 Novembre 1918, F-69622 Villeurbanne Cedex, France and Max-Planck Institut, Inselstrasse 22, 04103 Leipzig, Germany
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31
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Han GR, Jang CH. Liquid crystal sensor for the detection of acetylcholine using acetylcholinesterase immobilized on a nanostructured polymeric surface. Colloid Polym Sci 2015. [DOI: 10.1007/s00396-015-3648-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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A cationic surfactant-decorated liquid crystal sensing platform for simple and sensitive detection of acetylcholinesterase and its inhibitor. Biosens Bioelectron 2015; 72:25-30. [PMID: 25957073 DOI: 10.1016/j.bios.2015.05.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 04/25/2015] [Accepted: 05/01/2015] [Indexed: 01/15/2023]
Abstract
In this paper, construction of the liquid crystal (LC)-based sensing platform for simple and sensitive detection of acetylcholinesterase (AChE) and its inhibitor using a cationic surfactant-decorated LC interface was demonstrated. A change of the optical images of LCs from bright to dark appearance was observed when the cationic surfactant, myristoylcholine chloride (Myr), was transferred onto the aqueous/LC interface, due to the formation of a stable surfactant monolayer at the interface. A dark-to-bright change of the optical appearance was then observed when AChE was transferred onto the Myr-decorated LC interface. The sensitivity of this new type of LC-based sensor is 3 orders of magnitude higher in the serum albumin solution than that only in the buffer solution. Noteworthy is that the AChE LC sensor shows a very high sensitivity for the detection of the enzyme inhibitor, which is around 1 fM. The constructed low-cost LC-based sensor is quite simple and convenient, showing high promise for label-free detection of AChE and its inhibitors.
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33
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Sun SH, Lee MJ, Lee YH, Lee W, Song X, Chen CY. Immunoassays for the cancer biomarker CA125 based on a large-birefringence nematic liquid-crystal mixture. BIOMEDICAL OPTICS EXPRESS 2015; 6:245-56. [PMID: 25657889 PMCID: PMC4317129 DOI: 10.1364/boe.6.000245] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 12/07/2014] [Accepted: 12/18/2014] [Indexed: 05/05/2023]
Abstract
The use of fluorescence is ubiquitously found in the detection of immunoreaction; though with good sensitivity, this technique requires labeling as well as other time-consuming steps to perform the measurement. An alternative approach involving liquid crystals (LCs) was proposed, based on the fact that an immunocomplex can disturb the orientation of LCs, leading to an optical texture different from the case when only antigen or antibody exists. This method is label-free, easy to manipulate and low-cost. However, its sensitivity was low for practical usage. In this study, we adopted a high-birefringence liquid crystal (LC) to enhance the sensitivity for the immunodetection. Experiments were performed, targeting at the cancer biomarker CA125. We showed that the larger birefringence (Δn = 0.33 at 20 °C) amplifies the detected signal and, in turn, dramatically improves the detection limit. To avoid signal loss from conventional rinsing steps in immunodetection, CA125 antigen and antibody were reacted before immobilized on substrates. We studied the specific binding events and obtained a detection limit as low as 1 ng/ml. The valid temperature ranges were compared by using the typical single-compound LC 5CB and the high-birefringence LC mixture. We further investigated time dependency of the optical textures and affirmed the capability of LC-based immunodetection in distinguishing between specific and nonspecific antibodies.
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Affiliation(s)
- Shih-Hung Sun
- Institute of Imaging and Biomedical Photonics, College of Photonics, National Chiao Tung University, Guiren Dist., Tainan 71150,
Taiwan
| | - Mon-Juan Lee
- Department of Bioscience Technology, Chang Jung Christian University, Guiren Dist., Tainan 71101,
Taiwan
- (M.-J. Lee)
| | - Yun-Han Lee
- Institute of Imaging and Biomedical Photonics, College of Photonics, National Chiao Tung University, Guiren Dist., Tainan 71150,
Taiwan
| | - Wei Lee
- Institute of Imaging and Biomedical Photonics, College of Photonics, National Chiao Tung University, Guiren Dist., Tainan 71150,
Taiwan
- (W. Lee)
| | - Xiaolong Song
- Jiangsu Hecheng Display Technology Co., Ltd., Nanjing 210014,
China
| | - Chao-Yuan Chen
- Jiangsu Hecheng Display Technology Co., Ltd., Nanjing 210014,
China
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34
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Detection of heavy-metal ions using liquid crystal droplet patterns modulated by interaction between negatively charged carboxylate and heavy-metal cations. Talanta 2014; 128:44-50. [DOI: 10.1016/j.talanta.2014.04.026] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 04/05/2014] [Accepted: 04/17/2014] [Indexed: 11/18/2022]
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35
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Giura S, Schoen M. Density-functional theory and Monte Carlo simulations of the phase behavior of a simple model liquid crystal. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:022507. [PMID: 25215749 DOI: 10.1103/physreve.90.022507] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Indexed: 06/03/2023]
Abstract
We consider the phase behavior of a simple model of a liquid crystal by means of modified mean-field density-functional theory (MMF DFT) and Monte Carlo simulations in the grand canonical ensemble (GCEMC). The pairwise additive interactions between liquid-crystal molecules are modeled via a Lennard-Jones potential in which the attractive contribution depends on the orientation of the molecules. We derive the form of this orientation dependence through an expansion in terms of rotational invariants. Our MMF DFT predicts two topologically different phase diagrams. At weak to intermediate coupling of the orientation dependent attraction, there is a discontinuous isotropic-nematic liquid-liquid phase transition in addition to the gas-isotropic liquid one. In the limit of strong coupling, the gas-isotropic liquid critical point is suppressed in favor of a fluid- (gas- or isotropic-) nematic phase transition which is always discontinuous. By considering three representative isotherms in parallel GCEMC simulations, we confirm the general topology of the phase diagram predicted by MMF DFT at intermediate coupling strength. From the combined MMF DFT-GCEMC approach, we conclude that the isotropic-nematic phase transition is very weakly first order, thus confirming earlier computer simulation results for the same model [see M. Greschek and M. Schoen, Phys. Rev. E 83, 011704 (2011)].
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Affiliation(s)
- Stefano Giura
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin, Straße des 17. Juni 115, 10623 Berlin, Germany
| | - Martin Schoen
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin, Straße des 17. Juni 115, 10623 Berlin, Germany and Department of Chemical and Biomolecular Engineering, Engineering Building I, Box 7905, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, USA
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Nguyen TD, Carrillo JMY, Matheson MA, Brown WM. Rupture mechanism of liquid crystal thin films realized by large-scale molecular simulations. NANOSCALE 2014; 6:3083-3096. [PMID: 24264516 DOI: 10.1039/c3nr05413f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The ability of liquid crystal (LC) molecules to respond to changes in their environment makes them an interesting candidate for thin film applications, particularly in bio-sensing, bio-mimicking devices, and optics. Yet the understanding of the (in)stability of this family of thin films has been limited by the inherent challenges encountered by experiment and continuum models. Using unprecedented large-scale molecular dynamics (MD) simulations, we address the rupture origin of LC thin films wetting a solid substrate at length scales similar to those in experiment. Our simulations show the key signatures of spinodal instability in isotropic and nematic films on top of thermal nucleation, and importantly, for the first time, evidence of a common rupture mechanism independent of initial thickness and LC orientational ordering. We further demonstrate that the primary driving force for rupture is closely related to the tendency of the LC mesogens to recover their local environment in the bulk state. Our study not only provides new insights into the rupture mechanism of liquid crystal films, but also sets the stage for future investigations of thin film systems using peta-scale molecular dynamics simulations.
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Affiliation(s)
- Trung Dac Nguyen
- National Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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Dong Y, Yang Z. Beyond displays: The recent progress of liquid crystals for bio/chemical detections. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s11434-013-5767-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
The liquid crystal (LCD) biosensor is a new research area of sensor technology, which integrates the modern biotechnology and advanced electronic sensing technology. The feasibility and the principle of the LCD biosensor were mainly introduced in this paper. The chitosan films exhibited cholesteric phase LCD texture which can be seen by using the polarizing microscope (POM), and there is a main endothermic peak and exothermic peak of chitosan LCD solution in the DSC heating curve and cooling curve respectively. Chitosan maybe will be used as a sensing material by using its LCD characteristics. The development prospects are predicted.
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Park MK, Jang CH. High-Contrast Imaging of Biomolecular Interactions Using Liquid Crystals Supported on Roller Printed Protein Surfaces. B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.10.3269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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40
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Yoda T, Vestergaard MC, Hamada T, Le PTM, Takagi M. Thermo-induced Vesicular Dynamics of Membranes Containing Cholesterol Derivatives. Lipids 2012; 47:813-20. [DOI: 10.1007/s11745-012-3695-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 06/08/2012] [Indexed: 10/28/2022]
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41
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Chang CK, Bastiaansen CWM, Broer DJ, Kuo HL. Discrimination of Alcohol Molecules Using Hydrogen-Bridged Cholesteric Polymer Networks. Macromolecules 2012. [DOI: 10.1021/ma3007152] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chin-Kai Chang
- Department of Chemical Engineering
and Chemistry, Functional Materials and Devices, Eindhoven University of Technology, Eindhoven, Netherlands
- Materials & Chemical Research Laboratory, Industrial Technology Research Institute, Hsinchu, Taiwan
| | - Cees W. M. Bastiaansen
- Department of Chemical Engineering
and Chemistry, Functional Materials and Devices, Eindhoven University of Technology, Eindhoven, Netherlands
- School
of Engineering and Materials Science, Queen Mary University of London, London, U.K
| | - Dirk J. Broer
- Department of Chemical Engineering
and Chemistry, Functional Materials and Devices, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Hui-Lung Kuo
- Materials & Chemical Research Laboratory, Industrial Technology Research Institute, Hsinchu, Taiwan
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42
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Sohn EH, Kang H, Kim DG, Song K, Lee JC. Collapse of Homeotropic Liquid-Crystal Alignment by Increased Molecular Packing on Comb-Like Polymer Surfaces. Chemphyschem 2012; 13:2061-7. [DOI: 10.1002/cphc.201200051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/19/2012] [Indexed: 11/11/2022]
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43
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Hu QZ, Jang CH. Imaging trypsin activity through changes in the orientation of liquid crystals coupled to the interactions between a polyelectrolyte and a phospholipid layer. ACS APPLIED MATERIALS & INTERFACES 2012; 4:1791-1795. [PMID: 22394113 DOI: 10.1021/am300043d] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this study, we developed a new type of liquid crystal (LC)-based sensor for the real-time and label-free monitoring of enzymatic activity through changes in the orientation of LCs coupled to the interactions between polyelectrolyte and phospholipid. The LCs changed from dark to bright after an aqueous solution of poly-l-lysine (PLL) was transferred onto a self-assembled monolayer of the phospholipid, dioleoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium salt (DOPG), at the aqueous/LC interface. Interactions between the positively charged PLL and the negatively charged DOPG drove the reorganization of the phospholipid membrane, which induced an orientational transition in the LCs from a homeotropic to planar state. Since the serine endopeptidase trypsin can enzymatically catalyze the hydrolysis of PLL, the dark-to-bright shift in the optical response was not observed after transferring a mixed solution of PLL and trypsin onto the DOPG-decorated LC interface, indicating that no orientational transitions in the LCs occurred. However, the optical response from dark to bright was observed when the mixture in the optical cell was replaced by an aqueous solution of PLL. Control experiments with trypsin or an aqueous mixture of PLL and deactivated trypsin further confirmed the feasibility of this approach. The detection limit of trypsin was determined to be ~1 μg/mL. This approach holds great promise for use in the development of LC-based sensors for the detection of enzymatic reactions in cases where the biological polyelectrolyte substrates of enzymes could disrupt the organization of the membrane and induce orientational transitions of LCs at the aqueous/LC interface.
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Affiliation(s)
- Qiong-Zheng Hu
- Department of BioNano Technology, Gachon University, San 65, Bokjeong-Dong, Sujeong-Gu, Seongnam-City, Gyeonggi-Do, 461-701, Korea
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Hu QZ, Jang CH. A new strategy for imaging biomolecular events through interactions between liquid crystals and oil-in-water emulsions. Analyst 2012; 137:5204-7. [DOI: 10.1039/c2an35607d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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45
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Chen CH, Yang KL. Liquid crystal-based immunoassays for detecting hepatitis B antibody. Anal Biochem 2011; 421:321-3. [PMID: 22178912 DOI: 10.1016/j.ab.2011.11.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 10/30/2011] [Accepted: 11/08/2011] [Indexed: 11/16/2022]
Abstract
Conventional immunoassays are often fluorescence- or enzyme-based and require additional readout systems. Here, we report a liquid crystal (LC)-based immunoassay that features a new signal transduction mechanism, whereby the test results appear as colorful spots and can be viewed with the naked eye directly. By using the different colors of LC spots, we can estimate the range of anti-hepatitis B surface antigen concentrations between 300 and 15 nM. Because additional labeling process and readout systems are not required in this immunoassay, it is more suitable for point-of-care diagnosis of hepatitis B in resource-limited regions.
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Affiliation(s)
- Chih-Hsin Chen
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Singapore
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Sohn EH, Kim SH, Lee M, Lee JC, Song K. Surface properties and liquid crystal alignment behavior of poly(2-hydroxyethyl methacrylate) derivatives with alkyl ester side chains. J Colloid Interface Sci 2011; 360:623-32. [DOI: 10.1016/j.jcis.2011.04.070] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 04/13/2011] [Accepted: 04/19/2011] [Indexed: 11/30/2022]
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47
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Axenov KV, Laschat S. Thermotropic Ionic Liquid Crystals. MATERIALS 2011; 4:206-259. [PMID: 28879986 PMCID: PMC5448481 DOI: 10.3390/ma4010206] [Citation(s) in RCA: 273] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 12/27/2010] [Indexed: 12/26/2022]
Abstract
The last five years’ achievements in the synthesis and investigation of thermotropic ionic liquid crystals are reviewed. The present review describes the mesomorphic properties displayed by organic, as well as metal-containing ionic mesogens. In addition, a short overview on the ionic polymer and self-assembled liquid crystals is given. Potential and actual applications of ionic mesogens are also discussed.
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Affiliation(s)
- Kirill V Axenov
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
| | - Sabine Laschat
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
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48
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Prompinit P, Achalkumar AS, Bramble JP, Bushby RJ, Wälti C, Evans SD. Controlling liquid crystal alignment using photocleavable cyanobiphenyl self-assembled monolayers. ACS APPLIED MATERIALS & INTERFACES 2010; 2:3686-3692. [PMID: 21069978 DOI: 10.1021/am100832p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report on the development of novel cyano-biphenyl-based thiolate self-assembled monolayers designed to promote homeotropic alignment of calamitic liquid crystals. The molecules developed contain an ortho-nitrobenzyl protected carboxylic acid group that on irradiation by soft UV (365 nm) is cleaved to yield carboxylic acid groups exposed at the surface that promote planar alignment. Using a combination of wetting, X-ray photoelectron spectroscopy, Fourier transform-infrared reflection absorption spectroscopy, and ellipsometry we show that high photolysis yields (>90%) can be achieved and that the patterned SAMs are suitable for the controlled alignment of calamitic liquid crystals. This study further shows that such photo-patterned SAMs can be used to control the formation of focal conic domains (FCDs) in the smectic-A phase in terms of positioning and size confinement on surfaces.
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Affiliation(s)
- Panida Prompinit
- Molecular and Nanoscale Physics, School of Physics and Astronomy, Centre for Molecular Nanoscience (CMNS), and Institute of Microwaves and Photonics, University of Leeds, Leeds LS2 9JT, United Kingdom
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49
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Mazza MG, Greschek M, Valiullin R, Kärger J, Schoen M. Entropy-driven enhanced self-diffusion in confined reentrant supernematics. PHYSICAL REVIEW LETTERS 2010; 105:227802. [PMID: 21231424 DOI: 10.1103/physrevlett.105.227802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Indexed: 05/30/2023]
Abstract
We present a molecular dynamics study of reentrant nematic phases using the Gay-Berne-Kihara model of a liquid crystal in nanoconfinement. At densities above those characteristic of smectic A phases, reentrant nematic phases form that are characterized by a large value of the nematic order parameter S≃1. Along the nematic director these "supernematic" phases exhibit a remarkably high self-diffusivity, which exceeds that for ordinary, lower-density nematic phases by an order of magnitude. Enhancement of self-diffusivity is attributed to a decrease of rotational configurational entropy in confinement. Recent developments in the pulsed field gradient NMR technique are shown to provide favorable conditions for an experimental confirmation of our simulations.
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Affiliation(s)
- Marco G Mazza
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
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50
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Tan H, Yang S, Shen G, Yu R, Wu Z. Signal-Enhanced Liquid-Crystal DNA Biosensors Based on Enzymatic Metal Deposition. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201004272] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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