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Zhang X, Ding W, Jiao C, Kang X, Liu Z. Ultrasensitive Eu-Based MOF Luminescence Sensor for Clenbuterol Visible Recognition. Inorg Chem 2024; 63:3383-3392. [PMID: 38315637 DOI: 10.1021/acs.inorgchem.3c03941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Clenbuterol (CLB) as an illegal feed additive may cause a great security risk to food safety. However, convenient and efficient detection means for CLB in practical application remain a formidable challenge. Herein, a stable Eu-based organic framework {[H2N(CH3)2]2[Eu2(ttca)2]·H2O}n (compound 1) (H4ttca = [1,1':2',1″-terphenyl]-4,4',4″,5'-tetracarboxylic acid) has been harvested, exhibiting excellent chemical stability and thermal stability. Luminescence investigation reveals that compound 1 can sensitively and selectively detect CLB without being affected by different components from simulated serum and urine (limit detection: 22.7 nM). Furthermore, sensor 1 can also be applicable to CLB recognition in real swine feeds, presenting excellent anti-interference performance. The good cyclicity of compound 1 endows CLB determination with many advantages: low cost, high stability, and simplicity. Importantly, in view of the indication of the luminescence color (red to blue), test membranes were fabricated and employed for convenient and fast CLB detection, providing a valuable scheme for the visual monitoring of CLB in meat products. This work enriches rare earth metal compounds and luminescence sensor portfolios and breaks the concentration record (nM) for detecting CLB compared with reported complex materials, providing an effective monitoring platform for CLB visually.
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Affiliation(s)
- Xudong Zhang
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China
- State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization, Baotou Research Institute of Rare Earths, Baotou 014030, P. R. China
| | - Wenyu Ding
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China
| | - Chuanbao Jiao
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China
| | - Xiaomin Kang
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China
| | - Zhiliang Liu
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China
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Guo Q, Peng Y, Qin J, Chao K, Zhao X, Yin T. Advance in Detection Technique of Lean Meat Powder Residues in Meat Using SERS: A Review. Molecules 2023; 28:7504. [PMID: 38005225 PMCID: PMC10673115 DOI: 10.3390/molecules28227504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/31/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Food that contains lean meat powder (LMP) can cause human health issues, such as nausea, headaches, and even death for consumers. Traditional methods for detecting LMP residues in meat are often time-consuming and complex and lack sensitivity. This article provides a review of the research progress on the use of surface-enhanced Raman spectroscopy (SERS) technology for detecting residues of LMP in meat. The review also discusses several applications of SERS technology for detecting residues of LMP in meat, including the enhanced detection of LMP residues in meat based on single metal nanoparticles, combining metal nanoparticles with adsorbent materials, combining metal nanoparticles with immunizing and other chemicals, and combining the SERS technology with related techniques. As SERS technology continues to develop and improve, it is expected to become an even more widely used and effective tool for detecting residues of LMP in meat.
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Affiliation(s)
- Qinghui Guo
- College of Engineering, China Agricultural University, Beijing 100083, China
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Yankun Peng
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Jianwei Qin
- USDA/ARS Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, 10300 Baltimore Ave., Beltsville, MD 20705, USA
| | - Kuanglin Chao
- USDA/ARS Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, 10300 Baltimore Ave., Beltsville, MD 20705, USA
| | - Xinlong Zhao
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Tianzhen Yin
- College of Engineering, China Agricultural University, Beijing 100083, China
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Chen P, Hu C, Tao X, Zhou Z, Wang L, Yang X, Che Z, Chen X, Huang Y. Recognition mechanism and sequence optimization of organophosphorus pesticides aptamers for better monitoring contaminations in food. FOOD SCIENCE AND HUMAN WELLNESS 2023. [DOI: 10.1016/j.fshw.2023.02.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
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Nagano M, Toda T, Makino K, Miki H, Sugizaki Y, Tomizawa H, Isobayashi A, Yoshimoto K. Discovery of a Highly Specific Anti-methotrexate (MTX) DNA Aptamer for Antibody-Independent MTX Detection. Anal Chem 2022; 94:17255-17262. [PMID: 36449359 DOI: 10.1021/acs.analchem.2c04182] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
High-dose methotrexate (MTX) therapy is used to treat a wide variety of cancers such as leukemia and lymphoma, while the resulting high blood concentration of MTX faces a risk of life-threatening side effects, so it is essential to monitor the concentration carefully. Currently, the MTX concentration is measured using antibody-based kits in a clinical setting; however, the heterogeneity and batch-to-batch variation of antibodies potentially compromise the detection limit. Here, we developed MTX detection systems with chemically synthesizable homogeneous oligonucleotides. Microbead-assisted capillary electrophoresis (MACE)-SELEX against MTX successfully identified MSmt7 with a similar level of specificity to anti-MTX antibodies within three rounds. The 3'-end of MSmt7 was coupled to a peroxidase-like hemin-DNAzyme to construct a bifunctional oligonucleotide for MTX sensing, where MTX in 50% human serum was detected with a limit of detection (LoD) of 118 nM. Furthermore, amplifying the DNAzyme region with rolling circle amplification significantly improved the sensitivity with an LoD of 290 pM. Presented oligonucleotide-based MTX detection systems will pave the way for antibody-independent MTX detection with reliability and less cost in the laboratory and the clinic.
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Affiliation(s)
- Masanobu Nagano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Takumi Toda
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Kurumi Makino
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Hiroko Miki
- Corporate Research & Development Center, Toshiba Corporation, Kanagawa 212-8582, Japan
| | - Yoshiaki Sugizaki
- Corporate Research & Development Center, Toshiba Corporation, Kanagawa 212-8582, Japan
| | - Hideyuki Tomizawa
- Corporate Research & Development Center, Toshiba Corporation, Kanagawa 212-8582, Japan
| | - Atsunobu Isobayashi
- Corporate Research & Development Center, Toshiba Corporation, Kanagawa 212-8582, Japan
| | - Keitaro Yoshimoto
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
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Guo Q, Peng Y, Zhao X, Chen Y. Rapid Detection of Clenbuterol Residues in Pork Using Enhanced Raman Spectroscopy. BIOSENSORS 2022; 12:859. [PMID: 36290996 PMCID: PMC9599483 DOI: 10.3390/bios12100859] [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: 09/06/2022] [Revised: 10/05/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Clenbuterol (CB) is a synthetic β-receptor agonist which can be used to improve carcass leanness in swine, but its residues in pork also pose health risks. In this report, surface-enhanced Raman scattering (SERS) technology was used to achieve rapid detection and identification of clenbuterol hydrochloride (CB) residues. First, the effects of several different organic solvents on the extraction efficiency were compared, and it was found that clenbuterol in pork had a better enhancement effect using ethyl acetate as an extraction agent. Then, SERS signals of clenbuterol in different solvents were compared, and it was found that clenbuterol had a better enhancement effect in an aqueous solution. Therefore, water was chosen as the solvent for clenbuterol detection. Next, enhancement effect was compared using different concentration of sodium chloride solution as the aggregating compound. Finally, pork samples with different clenbuterol content (1, 3, 5, 7, 9, and 10 µg/g) were prepared for quantitative analysis. The SERS spectra of samples were collected with 0.5 mol/L of NaCl solution as aggregating compound and gold colloid as an enhanced substrate. Multiple scattering correction (MSC) and automatic Whittaker filter (AWF) were used for preprocessing, and the fluorescence background contained in the original Raman spectra was removed. A unary linear regression model was established between SERS intensity at 1472 cm-1 and clenbuterol content in pork samples. The model had a better linear relationship with a correlation coefficient R2 of 0.99 and a root mean square error of 0.263 µg/g. This method can be used for rapid screening of pork containing clenbuterol in the market.
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Li T, Wang J, Zhu L, Li C, Chang Q, Xu W. Advanced screening and tailoring strategies of pesticide aptamer for constructing biosensor. Crit Rev Food Sci Nutr 2022; 63:10974-10994. [PMID: 35699641 DOI: 10.1080/10408398.2022.2086210] [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] [Indexed: 11/03/2022]
Abstract
The rapid development of aptamers has helped address the challenges presented by the wide existed pesticides contaminations. Screening of aptamers with excellent performance is a prerequisite for successfully constructing biosensors, while further tailoring of aptamers with enhanced activity greatly improved the assay performance. Firstly, this paper reviewed the advanced screening strategies for pesticides aptamers, including immobilization screening that preserves the native structures of targets, non-immobilized screening based on nanomaterials, capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX), virtual screening in silico, high-throughput selection, and rational secondary library generation methods, which contributed significantly to improve the success rate of screening, reduce the screening time, and ensure aptamer binding affinity. Secondly, the precise tailoring strategies for pesticides aptamers were modularly elaborated, containing deletion, splitting, elongation, and fusion, which provided various advantages like cost-efficiency, enhanced binding affinity, and new derived functional motifs. Thirdly, the developed aptamer-based biosensors (aptasensors) for pesticide detection were systematically reviewed according to the different signal output modes. Finally, the challenges and future perspectives of pesticide detection are discussed comprehensively.
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Affiliation(s)
- Tianshun Li
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Jia Wang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
| | - Longjiao Zhu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
| | - Chenwei Li
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Qiaoying Chang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
| | - Wentao Xu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University,, Beijing, China
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Liu R, Zhang F, Sang Y, Katouzian I, Jafari SM, Wang X, Li W, Wang J, Mohammadi Z. Screening, identification, and application of nucleic acid aptamers applied in food safety biosensing. Trends Food Sci Technol 2022. [DOI: 10.1016/j.tifs.2022.03.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Guo X, Chen GH. Capillary electrophoresis-based methodology for screening of oligonucleotide aptamers. Biomed Chromatogr 2021; 35:e5109. [PMID: 33660332 DOI: 10.1002/bmc.5109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 01/28/2023]
Abstract
As a new molecular recognition element, oligonucleotide aptamer not only has higher affinity and specificity to target molecules, but also has the advantages of wide recognition range, in vitro synthesis and chemical stability compared with conventional antibodies. Since a kind of screening method termed systematic evolution of ligands by exponential enrichment (SELEX) was reported, scientists have extensively researched the methodology of how to highly and efficiently screen out aptamers from a library consisting of a large number of random oligonucleotides. Certainly capillary electrophoresis-based screening methodologies, including nonequilibrium capillary electrophoresis of equilibrium mixtures, equilibrium capillary electrophoresis of equilibrium mixtures, non-SELEX, ideal-filter capillary electrophoresis, capillary transient isotachophoresis, etc., are revolutionary. Compared with conventional SELEX, these capillary electrophoresis-based methodologies show incomparable advantages such as the single-round screening of aptamers and increased successful screening rate. Methodology studies on the screening process of aptamers are comprehensively reviewed.
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Affiliation(s)
- Xin Guo
- College of Food and Bioengineering, Jiangsu University, Zhenjiang, China.,Periodicals Agency of Jiangsu University, Zhenjiang, China
| | - Guan-Hua Chen
- College of Food and Bioengineering, Jiangsu University, Zhenjiang, China
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Selection and Identification of Common Aptamers against Both Vibrio Harveyi and Vibrio Alginolyticus. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60018-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Screening of Aptamer for Human IgG Fc Fragment by Capillary Electrophoresis-Systematic Evolution of Ligands by Exponential Enrichment. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60016-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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WANG ZJ, CHEN EN, YANG G, ZHAO XY, QU F. Research Advances of Aptamers Selection for Small Molecule Targets. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60013-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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ZHU C, ZHAO XY, YANG G, QU F. Capillary Electrophoresis Involving in High Efficiency Screening for Aptamers. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [PMCID: PMC7219368 DOI: 10.1016/s1872-2040(20)60014-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Systematic evolution of ligands by exponential enrichment (SELEX) is a universal technology for aptamer' screening. Accurate and efficient screening methods and strategy design are the key to success. This review briefly summarizes capillary electrophoresis (CE) involving in the efficient screening for aptamers in our group since 2007, including the application of CE in pre-screening, screening and post-screening process, classification and screening strategies against different protein targets, multiple screening modes, and screening for multi-scale targets. Finally, combined with the current progresses of aptamer screening, some remaining issues are discussed and the development prospects are proposed.
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LI LS, ZHU C, ZHAO Y, YANG G, QU F. Investigation of Library Input on Aptamers Selection Efficiency Using Capillary Electrophoresis. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60017-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Zhu C, Yang G, Ghulam M, Li L, Qu F. Evolution of multi-functional capillary electrophoresis for high-efficiency selection of aptamers. Biotechnol Adv 2019; 37:107432. [PMID: 31437572 DOI: 10.1016/j.biotechadv.2019.107432] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 06/24/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023]
Abstract
Aptamers have drawn considerable attention as newly emerging molecular recognition elements in clinical diagnostics, drug delivery, therapeutics, environmental monitoring, and food safety analyses. As the in vitro screening antibody analogs, aptamers are enabled to recognize various types of targets with high affinity and specificity like or even superior to antibodies. However, the restrictions and inefficiency of selection have been hampering their wider application. Among various modified systematic evolution of ligands by exponential enrichment (SELEX) methods, capillary electrophoresis (CE)-SELEX holds multiple functions and advantages with the powerful qualitative and quantitative analysis capabilities, less consumption of sample and analytical reagent, natural binding environment, higher screening efficiency, and availability in multiple modes. This review summarizes the key developments in the area of CE-SELEX by leading research groups, including our teams' ten years of research and experience to help researchers fully understand and utilize CE-SELEX. Aptamers' history, applications, as well as the SELEX developments, have been briefly described; the advantages of CE-SELEX are highlighted compared with the conventional SELEX methods. Further, we describe some essential CE-SELEX models and provide an overview of the CE-SELEX, including the targets and ssDNA library, every technical point in the selection process, and post-SELEX protocol. We expect this review will inspire more researchers to have insight into the screening problems from CE-SELEX viewpoint and will help to improve the selection efficiency and probability of success to meet the growing needs of aptamers' discovery in bioanalytical and medical fields.
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Affiliation(s)
- Chao Zhu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, China
| | - Ge Yang
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, China
| | - Murtaza Ghulam
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, China
| | - Linsen Li
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, China
| | - Feng Qu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, China.
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High-efficiency selection of aptamers for bovine lactoferrin by capillary electrophoresis and its aptasensor application in milk powder. Talanta 2019; 205:120088. [PMID: 31450439 DOI: 10.1016/j.talanta.2019.06.088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/14/2019] [Accepted: 06/26/2019] [Indexed: 02/07/2023]
Abstract
Capillary electrophoresis-based systematic evolution of ligands by exponential enrichment (CE-SELEX) is a high-efficient technique for aptamers selection, and has been evolved into many modes. In this study, we obtained the aptamer against bovine lactoferrin (BLF) with high affinity (dissociation constant, Kd = 20.74 ± 6.89 nM) and good specificity (>1000 folds) using single step CE-SELEX (ssCE-SELEX) mode. In the selection process, ssCE demonstrated high-efficiency selection with bulk Kd reaching at 0.19 ± 0.04 μM by only two rounds, as compared to capillary zone electrophoresis (CZE) mode with Kd of 0.39 ± 0.03 μM. Next-generation sequencing (NGS) was performed by two methods of high output (Hiseq) and medium output (Miseq) with different sequencing depths, and their same results of high-frequency sequences confirmed the reliability of the obtained sequences. Through affinity analysis, the primer region and single base mutation (SBM) were observed to affect the sequence structure and to result in affinity change. Besides, molecular dynamics (MD) simulation was performed to validate the binding affinity of the candidates with BLF by analyzing binding sites, interaction forces, and binding free energy. Moreover, BLF detection in milk powder matrices was completed successfully with the optimized CE-aptasensor. The signal response was in a good linear relationship (R2 = 0.9930) with 4-128 nM of BLF and the detection limit was 1 nM. The obtained results of BLF in four milk powder samples were in an acceptable agreement with the labeled concentrations. This study presented a completed CE based process including aptamers selection, affinity characterization, and detection application, which also validated the high-efficiency selection of ssCE-SELEX mode.
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Online reaction based single-step capillary electrophoresis-systematic evolution of ligands by exponential enrichment for ssDNA aptamers selection. Anal Chim Acta 2019; 1070:112-122. [PMID: 31103164 DOI: 10.1016/j.aca.2019.04.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/19/2019] [Accepted: 04/15/2019] [Indexed: 12/29/2022]
Abstract
Capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) has proven to be an effective technique for aptamers selection. In this study, we present an online reaction based convenient single-step CE-SELEX (ssCE-SELEX) mode with human thrombin (H-Thr) as a model target. The selection progress was monitored through bulk Kd analysis, which showed more than a 1000-fold improvement over the initial library after two rounds of selection. Three selected candidate sequences presented high binding affinities against H-Thr with nanomolar (nM) Kd determined by nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM, 56.4-177.1 nM) and CE based non-linear fitting (CE-NLF, 98.2-199.7 nM). They also exhibited high specificities towards H-Thr compared with bovine thrombin, IgG, lysozyme, and lactoferrin. Meanwhile, the Kd results by isothermal titration calorimetry (ITC) confirmed the effective CE in measuring the aptamer affinity. In addition, three candidates were applied as aptasensors in the AuNPs based colorimetric assay, which showed visible color change and good linear relationships (R2 > 0.93) with H-Thr concentration. Furthermore, molecular dynamics (MD) simulation was performed to validate the binding of the three candidates with H-Thr by binding sites and binding free energy. The ssCE-SELEX method avoids off-line incubation, saves time and sample, and may provide a universal and convenient method for aptamers selection.
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