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Zhan T, Feng XZ, Cheng YY, Han GC, Chen Z, Kraatz HB. Electrochemical sensor for ultrasensitive sensing of biotin based on heme conjugated with gold nanoparticles and its electrooxidation mechanism. Food Chem 2023; 429:136997. [PMID: 37516051 DOI: 10.1016/j.foodchem.2023.136997] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/19/2023] [Accepted: 07/23/2023] [Indexed: 07/31/2023]
Abstract
We report the fabrication of a facile sensor using heme conjugated with gold nanoparticles (AuNPs) in situ on a glass carbon electrode (GCE) for the ultrasensitive determination of biotin without antibody or streptavidin. The use of heme and AuNPs as dual amplifiers allows a very broad detection range from 0.0050 to 50.0000 μmol·L-1 and a very low detection limit of 0.0016 μmol·L-1. The mechanistic aspects were elucidated using electrochemical analyses and frontier orbital calculations showing that the electrooxidation of biotin involves a one-electron and a one-proton transfer, generating biotin sulfoxide. The heme/AuNPs/GCE sensor exhibited excellent selectivity, reproducibility and stability, indicating high robustness. The recovery was between 97.20 and 105.70% with RSD less than 8.71%, suggesting good practicability. Our studies demonstrate that this approach can be used to detect and quantify biotin in a range of foods, including milk, infant formula, flour, orange juice, mango juice, egg white and egg yolk. Furthermore, all measurements do not require any intricate preparation or pre-treatment of the foods, thus representing a great potential for point-of-care testing.
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Affiliation(s)
- Tao Zhan
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004, PR China
| | - Xiao-Zhen Feng
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004, PR China
| | - Yun-Yun Cheng
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004, PR China
| | - Guo-Cheng Han
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004, PR China.
| | - Zhencheng Chen
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin 541004, PR China.
| | - Heinz-Bernhard Kraatz
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada.
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2
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Meng W, Wang L, Du X, Xie M, Yang F, Li F, Wu ZE, Gan J, Wei H, Cao C, Lu S, Cao B, Li L, Li L, Zhu G. Engineered mesenchymal stem cell-derived extracellular vesicles constitute a versatile platform for targeted drug delivery. J Control Release 2023; 363:235-252. [PMID: 37739016 DOI: 10.1016/j.jconrel.2023.09.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 09/06/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023]
Abstract
Extracellular vesicles (EVs) are promising therapeutic carriers owing to their ideal size range and intrinsic biocompatibility. However, limited targeting ability has caused major setbacks in the clinical application of EV therapeutics. To overcome this, we genetically engineered natural free streptavidin (SA) on the cellular surface of bone marrow mesenchymal stem cells (BMSCs) and obtained typical EVs from these cells (BMSC-EVs). Biotin-coated gold nanoparticles confirmed the expression of SA on the membrane of EVs, which has a high affinity for biotinylated molecules. Using a squamous cell carcinoma model, we demonstrated that a pH-sensitive fusogenic peptide -modification of BMSC-EVs achieved targetability in the microenvironment of a hypoxic tumor to deliver anti-tumor drugs. Using EGFR+HER2- and EGFR-HER2+ breast cancer models, we demonstrated that anti-EGFR and anti-HER2 modifications of BMSC-EVs were able to specifically deliver drugs to EGFR+ and HER2+ tumors, respectively. Using a collagen-induced arthritis model, we confirmed that anti-IL12/IL23-modified BMSC-EVs specifically accumulated in the arthritic joint and alleviated inflammation. Administration of SA-overexpressing BMSC-EVs has limited immunogenicity and high safety in vivo, suggesting that BMSC-derived EVs are ideal drug delivery vehicle. These representative scenarios of targeting modification suggest that, using different biotinylated molecules, the SA-overexpressing BMSC-EVs could be endowed with different targetabilities, which allows BMSC-EVs to serve as a versatile platform for targeted drug delivery under various situations.
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Affiliation(s)
- Wanrong Meng
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Linlin Wang
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Xueyu Du
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Mingzhe Xie
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Fan Yang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Fei Li
- Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, 610041 Chengdu, China
| | - Zhanxuan E Wu
- Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, 610041 Chengdu, China
| | - Jianguo Gan
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Hongxuan Wei
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Chang Cao
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Shun Lu
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Bangrong Cao
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Longjiang Li
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Ling Li
- Sichuan Key Laboratory of Radiation Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610041 Chengdu, China
| | - Guiquan Zhu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Head and Neck Oncology, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China.
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3
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Ye W, Zhang Z, Wang C, Feng Z, Hu Z, Liu Q, Wu T. Detection of small molecules by extending the terminal protection to the polymerase. Microchem J 2023. [DOI: 10.1016/j.microc.2023.108701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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4
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Xiao Q, Chen M, Nie W, Xie F, Yu X, Ma C. A Fluorescent Biosensor for Streptavidin Detection Based on Double-Hairpin DNA-Templated Copper Nanoparticles. BIOSENSORS 2023; 13:168. [PMID: 36831934 PMCID: PMC9953726 DOI: 10.3390/bios13020168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/15/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
In this paper, we developed a sensitive, label-free and facile fluorescent strategy for detecting streptavidin (SA) based on double-hairpin DNA-templated copper nanoparticles (CuNPs) and terminal protection of small molecule-linked DNA. Herein, a special DNA hairpin probe was designed and synthesized, which contained two poly T single-stranded loops and a nick point in the middle of the stem. Inspired by the concept of the terminal protection interaction, the specific binding of SA to the biotinylated DNA probe can prevent the exonuclease degradation and keep the integrity of DNA probe, which can be used for synthesizing fluorescent CuNPs as a template. Conversely, the DNA probe would be digested by exonucleases and therefore, would fail to form CuNPs without SA. After systematic optimization, the detection range of SA concentration is from 0.5 to 150 nM with a low detection limit of 0.09 nM. Additionally, the proposed method was also successfully applied in the biological samples. Finally, the proposed method is sensitive, effective and simple, and can be potentially applied for predicting diseases and discovering new drugs.
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Affiliation(s)
- Qiangsheng Xiao
- Department of Hepatobiliary and Pancreatic Surgery, The Third Xiangya Hospital of Central South University, Changsha 410013, China
| | - Mingjian Chen
- School of Life Sciences, Central South University, Changsha 410017, China
| | - Wanpin Nie
- Department of Hepatobiliary and Pancreatic Surgery, The Third Xiangya Hospital of Central South University, Changsha 410013, China
| | - Fengjiao Xie
- The Third Affiliated Hospital of Southern Medical University, Guangzhou 510640, China
| | - Xiao Yu
- Department of Hepatobiliary and Pancreatic Surgery, The Third Xiangya Hospital of Central South University, Changsha 410013, China
| | - Changbei Ma
- School of Life Sciences, Central South University, Changsha 410017, China
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Role of Förster Resonance Energy Transfer in Graphene-Based Nanomaterials for Sensing. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12146844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Förster resonance energy transfer (FRET)-based fluorescence sensing of various target analytes has been of growing interest in the environmental, bioimaging, and diagnosis fields. Graphene-based zero- (0D) to two-dimensional (2D) nanomaterials, such as graphene quantum dots (GQDs), graphene oxide (GO), reduced graphene oxide (rGO), and graphdiyne (GD), can potentially be employed as donors/acceptors in FRET-based sensing approaches because of their unique electronic and photoluminescent properties. In this review, we discuss the basics of FRET, as well as the role of graphene-based nanomaterials (GQDs, GO, rGO, and GD) for sensing various analytes, including cations, amino acids, explosives, pesticides, biomolecules, bacteria, and viruses. In addition, the graphene-based nanomaterial sensing strategy could be applied in environmental sample analyses, and the reason for the lower detection ranges (micro- to pico-molar concentration) could also be explained in detail. Challenges and future directions for designing nanomaterials with a new sensing approach and better sensing performance will also be highlighted.
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Esmaeili Y, Bidram E, Zarrabi A, Amini A, Cheng C. Graphene oxide and its derivatives as promising In-vitro bio-imaging platforms. Sci Rep 2020; 10:18052. [PMID: 33093483 PMCID: PMC7582845 DOI: 10.1038/s41598-020-75090-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/10/2020] [Indexed: 12/29/2022] Open
Abstract
Intrinsic fluorescence and versatile optical properties of Graphene Oxide (GO) in visible and near-infrared range introduce this nanomaterial as a promising candidate for numerous clinical applications for early-diagnose of diseases. Despite recent progresses in the impact of major features of GO on the photoluminescence properties of GO, their modifications have not yet systematically understood. Here, to study the modification effects on the fluorescence behavior, poly ethylene glycol (PEG) polymer, metal nanoparticles (Au and Fe3O4) and folic acid (FA) molecules were used to functionalize the GO surface. The fluorescence performances in different environments (water, DMEM cell media and phosphate buffer with two different pH values) were assessed through fluorescence spectroscopy and fluorescent microscopy, while Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) and Scanning electron microscopy (SEM) were utilized to evaluate the modifications of chemical structures. The modification of GO with desired molecules improved the photoluminescence property. The synthesized platforms of GO-PEG, GO-PEG-Au, GO-PEG-Fe3O4 and GO-PEG-FA illustrated emissions in three main fluorescence regions (blue, green and red), suitable for tracing and bio-imaging purposes. Considering MTT results, these platforms potentially positioned themselves as non-invasive optical sensors for the diagnosis alternatives of traditional imaging agents.
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Affiliation(s)
- Yasaman Esmaeili
- Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan, Iran
| | - Elham Bidram
- Biosensor Research Center, Department of Biomaterials, Nanotechnology, and Tissue Engineering, School of Advanced Technologies in Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Ali Zarrabi
- Nanotechnology Research and Application Center (SUNUM), Sabanci University, 34956, Tuzla, Istanbul, Turkey
| | - Abbas Amini
- Department of Mechanical Engineering, Australian College of Kuwait, 13015, Mishref, Safat, Kuwait.
| | - Chun Cheng
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China
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Yan Y, Ma C, Tang Z, Chen M, Zhao H. A novel fluorescent assay based on DNAzyme-assisted detection of prostate specific antigen for signal amplification. Anal Chim Acta 2020; 1104:172-179. [PMID: 32106949 DOI: 10.1016/j.aca.2020.01.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 11/23/2019] [Accepted: 01/07/2020] [Indexed: 12/13/2022]
Abstract
Prostate specific antigen (PSA) is one of the most common biomarkers for the management of prostate cancer. However, it still remains urgent to develop highly sensitive, cost-effective and selective strategies for PSA assay. In this paper, we developed a low-cost, highly sensitive and specific analytical strategy for the detection of PSA by using a fluorescence sensor based on Pb2+-dependent DNAzyme. We designed a DNA sequence called cmMB with a hairpin structure, containing PSA-specific aptamers and Pb2+-dependent DNAzyme chains. Also, a fluorophore-labelled DNA sequence called Sub-FAM, which contains a cleavage site of Pb2+-dependent DNAzyme and serves as substrate, is also designed for the signal generation. In the presence of PSA, interaction between aptamer and PSA blocks the hairpin structure of cmMB, resulting in the formation of Pb2+-dependent DNAzyme with Pb2+. Then, Pb2+-dependent DNAzyme can cleavage Sub-FAM and produce a high fluorescence. In the absence of PSA, since Sub-FAM remains to be ssDNA and can be absorbed by GO, only low fluorescence can be detected. Under optimal experimental conditions, a good linear relationship in the range of 1-100 pg mL-1 was exhibited, with a limit of detection (LOD) of 0.76 pg mL-1. In addition, the proposed method has potential value in the diagnosis and monitoring of prostate cancer because of its good selectivity and practical application in biological samples.
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Affiliation(s)
- Ying Yan
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Changbei Ma
- School of Life Sciences, Central South University, Changsha, 410013, China.
| | - Zhenwei Tang
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Mingjian Chen
- School of Life Sciences, Central South University, Changsha, 410013, China
| | - Han Zhao
- School of Life Sciences, Central South University, Changsha, 410013, China
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Cao SH, Li LH, Wei WY, Feng Y, Jiang WL, Wang JL, Zhang XP, Cai SH, Chen Z. A label-free and ultrasensitive DNA impedimetric sensor with enzymatic and electrical dual-amplification. Analyst 2019; 144:4175-4179. [PMID: 31237576 DOI: 10.1039/c9an00682f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In this work, we report a facile, sensitive, selective, and reproducible DNA impedimetric sensor device. We demonstrate that, combined with exonuclease III, the easily prepared electrochemically reduced graphene oxide (rGO) could be a desirable platform to amplify signals in electrochemical impedance spectroscopy for ultrasensitive DNA detection. Guided by enzyme assisted target recycling, efficient interfacial tuning can be obtained, from the situation with high impedance caused by single-stranded DNA probes directly adsorbed onto rGO to the one with low impedance due to the continuous desorption of target-probe DNA hybrids and the consequent digestion of DNA probes. Just a few DNA targets can specifically trigger the enzymatic digestion of a large number of DNA probes. It is the excellent electrical conductivity of rGO that further enlarges the changes of electron transfer resistance after the removal of DNA probes. As a result of synergistically combining both enzymatic and electrical amplification, the enlarged changes of impedimetric signals can be measured to sensitively report DNA targets. The specificity has been guaranteed by the intrinsic recognition of hybrids through both rGO and exonuclease III. A limit of detection as low as 10 aM target DNA in the matrix of cell culture medium, as well as a wide linear range and good discrimination of mismatched sequences even at the one-base level, suggests its great application prospect in biosensing and biomedical analysis. It also has other advantages including easy operation, low cost, and convenient regeneration, with more competitive performance in developing impedimetric biosensors.
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Affiliation(s)
- Shuo-Hui Cao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Electronic Science, Xiamen University, Xiamen 361005, P. R. China.
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Lee CY, Kim HY, Kim S, Park KS, Park HG. A simple and sensitive detection of small molecule-protein interactions based on terminal protection-mediated exponential strand displacement amplification. Analyst 2019; 143:2023-2028. [PMID: 29634063 DOI: 10.1039/c8an00099a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We herein describe a simple and sensitive strategy to detect a small molecule-protein interaction based on terminal protection-mediated exponential strand displacement amplification (eSDA). In principle, the small molecule linked to a DNA probe protects the DNA probe against the exonuclease I-catalyzed degradation after its binding to the corresponding target protein. The protected DNA probe then serves as a template to promote eSDA. Consequently, a large number of duplexes are produced, which leads to a high fluorescence from a double-stranded DNA specific fluorescent dye, SYBR Green I. As a model system to prove this sensing strategy, the interaction between biotin and streptavidin (SA), which is known to be the strongest among the non-covalent biological interactions, was selected and its analytical performance was thoroughly investigated. As a result, SA was sensitively detected with the limit of detection of 16 pM. In addition, the practical applicability of this method was successfully demonstrated by reliably determining the SA in human serum.
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Affiliation(s)
- Chang Yeol Lee
- Department of Chemical and Biomolecular Engineering (BK 21 + program), KAIST, Daehak-ro 291, Yuseong-gu, Daejeon 34141, Republic of Korea.
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Kahyaoglu LN, Rickus JL. Robust Covalent Coupling Scheme for the Development of FRET Aptasensor based on Amino-Silane-Modified Graphene Oxide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:14586-14596. [PMID: 30398888 DOI: 10.1021/acs.langmuir.8b02663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In recent years, numerous aptamers have been physisorbed on graphene oxide (GO) to develop fluorescence resonance energy transfer-based aptasensors using the fluorescence quenching property of GO. However, physisorbed aptasensors show poor signal reversibility and reproducibility as well as nonspecific probe displacement, and thereby are not suitable for many analytical applications. To overcome these problems when working with complex biological samples, we developed a facile and robust covalent surface functionalization technique for GO-based fluorescent aptasensors using a well-studied adenosine triphosphate binding aptamer (ABA). In the scheme, GO is first modified with amino-silane, and further with glutaraldehyde to create available carbonyl groups for the covalent attachment of a fluorophore and an amino dual modified ABA. The surface modification method was characterized by ζ-potential, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy (FTIR). The linearity, sensitivity, selectivity, and reversibility of the resulting GO-based covalent aptasensor was determined and systematically compared with the physisorbed aptasensor. Although both sensors showed similar performance in terms of sensitivity and linearity, better selectivity and higher resistance to nonspecific probe displacement was achieved with the developed covalent ABA sensor. The surface modification technique developed here is independent of the aptamer sequence, and therefore could be used universally for different analytical applications simply by changing the aptamer sequence for the target biomolecule.
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Tan W, Sun Z, Xuan L, Li J, Xie W, He C, Pan L. Development of BCPDA-Eu3+-BAS labeled hepatitis B surface antibodies. Chem Res Chin Univ 2018. [DOI: 10.1007/s40242-018-7295-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Zheng P, Wu N. Fluorescence and Sensing Applications of Graphene Oxide and Graphene Quantum Dots: A Review. Chem Asian J 2017; 12:2343-2353. [PMID: 28742956 PMCID: PMC5915373 DOI: 10.1002/asia.201700814] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/23/2017] [Indexed: 01/01/2023]
Abstract
Graphene oxide and graphene quantum dots are attractive fluorophores that are inexpensive, nontoxic, photostable, water-soluble, biocompatible, and environmentally friendly. They find extensive applications in fluorescent biosensors and chemosensors, in which they serve as either fluorophores or quenchers. As fluorophores, they display tunable photoluminescence emission and the "giant red-edge effect". As quenchers, they exhibit a remarkable quenching efficiency through either electron transfer or Förster resonance energy transfer (FRET) process. In this review, the origin of fluorescence and the mechanism of excitation wavelength-dependent fluorescence of graphene oxide and graphene quantum dots are discussed. Sensor design strategies based on graphene oxide and graphene quantum dots are presented. The applications of these sensors in health care, the environment, agriculture, and food safety are highlighted.
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Affiliation(s)
- Peng Zheng
- Department of Mechanical and Aerospace Engineering, West Virginia University, PO Box 6106, Morgantown, WV 26506 (USA)
| | - Nianqiang Wu
- Department of Mechanical and Aerospace Engineering, West Virginia University, PO Box 6106, Morgantown, WV 26506 (USA)
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