1
|
Khuda N, Somasundaram S, Urgunde AB, Easley CJ. Ionic Strength and Hybridization Position near Gold Electrodes Can Significantly Improve Kinetics in DNA-Based Electrochemical Sensors. ACS APPLIED MATERIALS & INTERFACES 2023; 15:5019-5027. [PMID: 36661270 PMCID: PMC10370289 DOI: 10.1021/acsami.2c22741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
A variety of electrochemical (EC) biosensors play critical roles in disease diagnostics. More recently, DNA-based EC sensors have been established as promising for detecting a wide range of analyte classes. Since most of these sensors rely on the high specificity of DNA hybridization for analyte binding or structural control, it is crucial to understand the kinetics of hybridization at the electrode surface. In this work, we have used methylene blue-labeled DNA strands to monitor the kinetics of DNA hybridization at the electrode surface with square-wave voltammetry. By varying the position of the double-stranded DNA segment relative to the electrode surface as well as the bulk solution's ionic strength (0.125-1.00 M), we observed significant interferences with DNA hybridization closer to the surface, with more substantial interference at lower ionic strength. As a demonstration of the effect, toehold-mediated strand displacement reactions were slowed and diminished close to the surface, while strategic placement of the DNA binding site improved reaction rates and yields. This work manifests that both the salt concentration and DNA hybridization site relative to the electrode are important factors to consider when designing DNA-based EC sensors that measure hybridization directly at the electrode surface.
Collapse
Affiliation(s)
- Niamat Khuda
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA
| | | | - Ajay B. Urgunde
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA
| | | |
Collapse
|
2
|
A novel ratiometric electrochemical aptasensor for highly sensitive detection of carcinoembryonic antigen. Anal Biochem 2022; 659:114957. [PMID: 36265690 DOI: 10.1016/j.ab.2022.114957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/09/2022] [Accepted: 10/13/2022] [Indexed: 12/14/2022]
Abstract
A novel ratiometric electrochemical aptasensor was proposed for carcinoembryonic antigen (CEA) detection based on exonuclease III (Exo III)-assisted recycling and rolling circle amplification (RCA) strategies. A thiolated ferrocene-labeled hairpin probe 2 (Fc-HP2) was fixed on the gold nanoparticles (AuNPs)-modified gold electrode (AuE) surface through Au-S bonds. The presence of CEA led to the release of trigger, which hybridized with the 3'-protruding of hairpin probe 1 (HP1) and triggered the Exo III cleavage reaction, accompanied by the releasing of trigger and generation of new DNA fragment which was used for the successive hybridization with Fc-HP2. After the Exo III cleavage process, the remaining Fc-HP2 fragments hybridized as primers with the RCA template to initiate the RCA process, and long single-stranded polynucleotides were produced for methylene blue (MB) binding. Such changes resulted in the signal of Fc (IFc) decreased and that of MB (IMB) increased, achieving a linear relationship between IMB/IFc and logarithm of CEA concentrations ranging from 1.0 pg mL-1 to 100.0 ng mL-1 with a detection limit of 0.59 pg mL-1. Additionally, the developed aptasensor had been successfully applied to detect CEA in human serum samples. Therefore, the proposed strategy might provide a new platform for clinical detections of CEA.
Collapse
|
3
|
Gao X, Qi L, Liu K, Meng C, Li Y, Yu HZ. Exonuclease I-Assisted General Strategy to Convert Aptamer-Based Electrochemical Biosensors from "Signal-Off" to "Signal-On". Anal Chem 2020; 92:6229-6234. [PMID: 32237711 DOI: 10.1021/acs.analchem.0c00005] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In terms of how the signal varies in response to increased concentration of an analyte, sensors can be classified as either "signal-on" or "signal-off" format. While both types hold potentials to be sensitive, selective, and reusable, in many situations "signal-on" sensors are preferred for their low background signal and better selectivity. In this study, with the detection of lysozyme using its DNA aptamer as a trial system, for the first time we demonstrated that such an aptamer-based electrochemical biosensor can be converted from intrinsically "signal-off" to "signal-on" with the aid of a DNA exonuclease. The fact that the stepwise cleavage of antilysozyme aptamer catalyzed by Exonuclease I (Exo I) is entirely inhibited upon binding lysozyme leads to the selective removal of unbound DNA probes (thiolate anti-lysozyme DNA aptamer strands immobilized on gold electrode) upon the introduction of Exo I to the sensor. With the aid of electrostatically bound redox cations ([Ru(NH3)6]3+), we were able to quantitate the number of aptamer strands that are bound with lysozymes via conventional cyclic voltammetry (CV) measurements. We demonstrated that Exo I-assisted signal-on conversion protocol not only improves the sensing performance (10 times better limit of detection) but also promises a versatile strategy for DNA-based biosensor design, i.e., it can be readily adapted to other aptamer-protein binding systems (thrombin, as another example).
Collapse
Affiliation(s)
- Xiaoyi Gao
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China.,Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Lin Qi
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Kun Liu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Chenchen Meng
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Yunchao Li
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Hua-Zhong Yu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| |
Collapse
|
4
|
Pei Q, Song X, Liu S, Wang J, Leng X, Cui X, Yu J, Wang Y, Huang J. A facile signal-on electrochemical DNA sensing platform for ultrasensitive detection of pathogenic bacteria based on Exo III-assisted autonomous multiple-cycle amplification. Analyst 2019; 144:3023-3029. [PMID: 30900712 DOI: 10.1039/c9an00036d] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A facile signal-on electrochemical DNA biosensor has been developed for ultrasensitive detection of pathogenic bacteria using an Exo III-assisted autonomous multiple-cycle amplification strategy. The strategy relies on pathogens and aptamer binding-initiated release of a trigger, which combines with the 3'-protruding terminus of the hairpin probe 1, leading to the formation of double-stranded DNA with a blunt 3' terminus which starts the Exo III-assisted multiple signal amplification reaction. In addition, hairpin probe 2 labeled with an electroactive reporter at the middle of the loop region is ingeniously designed to contain a short hairpin-embedded segment, which can fold into a hairpin structure via an Exo III-assisted cleavage reaction, thus bringing the redox molecule in proximity to the electrode surface for "signal-on" sensing. Under optimal conditions, this biosensor exhibits a very low detection limit as low as 8 cfu mL-1 and a wide linear range from 1.0 × 101 to 1.0 × 107 cfu mL-1 of target pathogenic bacteria. As far as we know, this is the first time that the Exo III-assisted autonomous multiple-cycle amplification strategy has been used for signal-on electrochemical sensing of pathogenic bacteria. In addition, the proposed sensor can also be used for highly sensitive detection of other targets by changing the aptamer sequence, such as nucleic acids, proteins and small molecules. Therefore, the proposed signal-on electrochemical sensing strategy might provide a simple and practical new platform for detection of pathogenic bacteria and related biological analysis, food safety inspection and environmental monitoring.
Collapse
Affiliation(s)
- Qianqian Pei
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China
| | - Xiaolei Song
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, P.R. China
| | - Su Liu
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, P.R. China
| | - Jingfeng Wang
- College of Biological Sciences and Technology, University of Jinan, Jinan 250022, P.R. China.
| | - Xueqi Leng
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, P.R. China
| | - Xuejun Cui
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China
| | - Jinghua Yu
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China
| | - Yu Wang
- College of Biological Sciences and Technology, University of Jinan, Jinan 250022, P.R. China.
| | - Jiadong Huang
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China and College of Biological Sciences and Technology, University of Jinan, Jinan 250022, P.R. China.
| |
Collapse
|
5
|
Mehlhorn A, Rahimi P, Joseph Y. Aptamer-Based Biosensors for Antibiotic Detection: A Review. BIOSENSORS-BASEL 2018; 8:bios8020054. [PMID: 29891818 PMCID: PMC6023021 DOI: 10.3390/bios8020054] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 06/04/2018] [Accepted: 06/05/2018] [Indexed: 02/06/2023]
Abstract
Antibiotic resistance and, accordingly, their pollution because of uncontrolled usage has emerged as a serious problem in recent years. Hence, there is an increased demand to develop robust, easy, and sensitive methods for rapid evaluation of antibiotics and their residues. Among different analytical methods, the aptamer-based biosensors (aptasensors) have attracted considerable attention because of good selectivity, specificity, and sensitivity. This review gives an overview about recently-developed aptasensors for antibiotic detection. The use of various aptamer assays to determine different groups of antibiotics, like β-lactams, aminoglycosides, anthracyclines, chloramphenicol, (fluoro)quinolones, lincosamide, tetracyclines, and sulfonamides are presented in this paper.
Collapse
Affiliation(s)
- Asol Mehlhorn
- Institute of Electronic and Sensory Materials, Faculty of Materials Science and Materials Technology, Technological University Freiberg, Akademie Str. 6, 09599 Freiberg, Germany.
| | - Parvaneh Rahimi
- Institute of Electronic and Sensory Materials, Faculty of Materials Science and Materials Technology, Technological University Freiberg, Akademie Str. 6, 09599 Freiberg, Germany.
| | - Yvonne Joseph
- Institute of Electronic and Sensory Materials, Faculty of Materials Science and Materials Technology, Technological University Freiberg, Akademie Str. 6, 09599 Freiberg, Germany.
| |
Collapse
|
6
|
Application of aptamers in detection and chromatographic purification of antibiotics in different matrices. Trends Analyt Chem 2017. [DOI: 10.1016/j.trac.2017.07.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|