title: Development of structure switching aptamer assay for detection of aflatoxin M1 in milk sample.
abstract: The discovery of in-vitro systematic evolution of ligands by exponential enrichment (SELEX) process has considerably broaden the utility of aptamer as bio-recognition element, providing the high binding affinity and specificity against the target analytes. Recent research has focused on the development of structure switching signaling aptamer assay, transducing the aptamer- target recognition event into an easily detectable signal. In this paper, we demonstrate the development of structure switching aptamer assay for determination of aflatoxin M1 (AFM1) employing the quenching-dequenching mechanism. Hybridization of fluorescein labelled anti-AFM1 aptamer (F-aptamer) with TAMRA labelled complementary sequences (Q-aptamer) brings the fluorophore and the quencher into close proximity, which results in maximum fluorescence quenching. On addition of AFM1, the target induced conformational formation of antiparallel G-quadruplex aptamer-AFM1 complex results in fluorescence recovery. Under optimized experimental conditions, the developed method showed the good linearity with limit of detection (LOD) at 5.0ngkg(-1) for AFM1. The specificity of the sensing platform was carefully investigated against aflatoxin B1 (AFB1) and ochratoxin A (OTA). The developed assay platform showed the high specificity towards AFM1. The practical application of the developed aptamer assay was verified for detection of AFM1 in spiked milk samples. Good recoveries were obtained in the range from 94.40% to 95.28% (n=3) from AFM1 spiked milk sample.
authors.affiliation: BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France; Biosensor Lab, Department of Chemistry, BITS, Pilani, K. K. Birla Goa Campus, Zuarinagar, Goa 403726, India.
authors.forename: Atul
authors.initials: A
authors.lastname: Sharma
authors.affiliation: BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France.
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Catanante
authors.affiliation: Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Lahore 54000, Pakistan; BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France.
authors.forename: Akhtar
authors.initials: A
authors.lastname: Hayat
authors.affiliation: BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Istamboulie
authors.affiliation: Biocatalysis and Industrial Enzymes Group, Laboratory of Microbial Ecology and Technology, Carthage University, National Institute of Applied Sciences and Technology, BP 676, 1080 Tunis, Tunisia; BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France.
authors.forename: Ines
authors.initials: I
authors.lastname: Ben Rejeb
authors.affiliation: Biosensor Lab, Department of Chemistry, BITS, Pilani, K. K. Birla Goa Campus, Zuarinagar, Goa 403726, India.
authors.forename: Sunil
authors.initials: S
authors.lastname: Bhand
authors.affiliation: BAE Laboratory, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan 66860, France. Electronic address: jlmarty@univ-perp.fr.
authors.forename: Jean Louis
authors.initials: JL
authors.lastname: Marty
mesh_terms: D016607:Aflatoxin M1 / Q000032:analysis* / Q000737:chemistry; D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001681:Biological Assay; D005453:Fluorescence; D005506:Food Contamination / Q000032:analysis; D054856:G-Quadruplexes; D008892:Milk / Q000737:chemistry*; D052156:SELEX Aptamer Technique
chemical_list: D052157:Aptamers, Nucleotide; D016607:Aflatoxin M1
keywords: Aflatoxin M1; Aptamer; Fluorescence quenching; Milk; Structure switchable aptamer assay