Novel single-stranded DNA binding protein-assisted fluorescence aptamer switch based on FRET for homogeneous detection of antibiotics.
Herein, a smart single-stranded DNA binding protein (SSB)-assisted fluorescence aptamer switch based on fluorescence resonance energy transfer (FRET) was designed. The FRET switch was synthesized by connecting SSB labeled quantum dots (QDs@SSB) as donor with aptamer (apt) labeled gold nanoparticles (AuNPs@apt) as acceptor, and it was employed for detecting chloramphenicol (CAP) in a homogenous solution. In the assay, the interaction between core-shell QDs@SSB and AuNPs@apt leads to a dramatic quenching (turning off). After adding CAP in the detection system, AuNPs@apt can bind the target specifically then separate QDs@SSB with AuNPs@apt-target, resulting in restoring the fluorescence intensity of QDs (turning on). Consequently, the fluorescence intensity recovers and the recovery extent can be used for detection of CAP in homogenous phase via optical responses. Under optimal conditions, the fluorescence intensity increased linearly with increasing concentrations of CAP from 0.005 to 100ngmL-1. The limit of this fluorescence aptamer switch was around 3pgmL-1for CAP detection. When the analyte is changed, the assay can be applied to detect other targets only by changing relative aptamer in AuNPs@apt probe. Furthermore, it has potential to be served as a simple, sensitive and portable platform for antibiotic contaminants detection in biological and environmental samples.
Faculty of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
Ye
Y
Wang
Faculty of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China. Electronic address: ganning@nbu.edu.cn.
Ning
N
Gan
Faculty of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
You
Y
Zhou
Faculty of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
Tianhua
T
Li
Faculty of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
Yuting
Y
Cao
Deptartment of Food Science and Engineering/Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210000, China.
Yinji
Y
Chen
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D002701:Chloramphenicol / Q000032:analysis*; D004268:DNA-Binding Proteins / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008892:Milk / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure
D000900:Anti-Bacterial Agents; D052157:Aptamers, Nucleotide; D004268:DNA-Binding Proteins; D002701:Chloramphenicol; D006046:Gold
Aptamer; Chloramphenicol; FRET switch; Gold nanoparticles; Quantum dots; Single strand DNA-binding protein