title: A novel sandwich-type electrochemical aptasensor based on GR-3D Au and aptamer-AuNPs-HRP for sensitive detection of oxytetracycline.
abstract: In this paper, a novel sandwich-type electrochemical aptasensor has been fabricated and applied for sensitive and selective detection of antibiotic oxytetracycline (OTC). This sensor was based on graphene-three dimensional nanostructure gold nanocomposite (GR-3D Au) and aptamer-AuNPs-horseradish peroxidase (aptamer-AuNPs-HRP) nanoprobes as signal amplification. Firstly, GR-3D Au film was modified on glassy carbon electrode only by one-step electrochemical coreduction with graphite oxide (GO) and HAuCl4at cathodic potentials, which enhanced the electron transfer and loading capacity of biomolecules. Then the aptamer and HRP modified Au nanoparticles provide high affinity and ultrasensitive electrochemical probe with excellent specificity for OTC. Under the optimized conditions, the peak current was linearly proportional to the concentration of OTC in the range of 5×10-10-2×10-3gL-1, with a detection limit of 4.98×10-10gL-1. Additionally, this aptasensor had the advantages in high sensitivity, superb specificity and showed good recovery in synthetic samples. Hence, the developed sandwich-type electrochemical aptasensor might provide a useful and practical tool for OTC determination and related food safety analysis and clinical diagnosis.
authors.affiliation: College of Resources and Environment, University of Jinan, Jinan 250022, PR China.
authors.forename: Su
authors.initials: S
authors.lastname: Liu
authors.affiliation: College of Biological Sciences and Technology, University of Jinan, Jinan 250022, PR China. Electronic address: bio_wangy@ujn.edu.cn.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.affiliation: College of Resources and Environment, University of Jinan, Jinan 250022, PR China.
authors.forename: Xueqi
authors.initials: X
authors.lastname: Leng
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Yuna
authors.initials: Y
authors.lastname: Guo
authors.affiliation: College of Biological Sciences and Technology, University of Jinan, Jinan 250022, PR China; Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Jiadong
authors.initials: J
authors.lastname: Huang
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods; D005504:Food Analysis / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry; D006722:Honey / Q000032:analysis; D006735:Horseradish Peroxidase / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010118:Oxytetracycline / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D052157:Aptamers, Nucleotide; D006046:Gold; D006108:Graphite; D006735:Horseradish Peroxidase; D010118:Oxytetracycline
keywords: Electrochemical aptasensor; Graphene-gold nanostructure; Horseradish peroxidase; Oxytetracycline; Sandwich-type