title: Selection and characterization of a novel DNA aptamer for label-free fluorescence biosensing of ochratoxin A.
abstract: Nucleic acid aptamers are emerging as useful molecular recognition tools for food safety monitoring. However, practical and technical challenges limit the number and diversity of available aptamer probes that can be incorporated into novel sensing schemes. This work describes the selection of novel DNA aptamers that bind to the important food contaminant ochratoxin A (OTA). Following 15 rounds of in vitro selection, sequences were analyzed for OTA binding. Two of the isolated aptamers demonstrated high affinity binding and selectivity to this mycotoxin compared to similar food adulterants. These sequences, as well as a truncated aptamer (minimal sequence required for binding), were incorporated into a SYBR® Green I fluorescence-based OTA biosensing scheme. This label-free detection platform is capable of rapid, selective, and sensitive OTA quantification with a limit of detection of 9 nM and linear quantification up to 100 nM.
authors.affiliation: Department of Bioengineering, Stanford University, 443 Via Ortega, MC 4245, Stanford, CA 94305, USA. mmckeagu@stanford.edu.
authors.forename: Maureen
authors.initials: M
authors.lastname: McKeague
authors.affiliation: Chemistry Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada. rvelunathan@gmail.com.
authors.forename: Ranganathan
authors.initials: R
authors.lastname: Velu
authors.affiliation: Chemistry Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada. khill3@connect.carleton.ca.
authors.forename: Kayla
authors.initials: K
authors.lastname: Hill
authors.affiliation: Department of Applied Biotechnology and Food Science, Budapest University of Technology Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary. bardoczy@richter.hu.
authors.forename: Viola
authors.initials: V
authors.lastname: Bardóczy
authors.affiliation: Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Tûzoltó u. 37-47, H-1094 Budapest, Hungary. meszaros.tamas@med.semmelweis-univ.hu.
authors.forename: Tamás
authors.initials: T
authors.lastname: Mészáros
authors.affiliation: Chemistry Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada. maria_derosa@carleton.ca.
authors.forename: Maria C
authors.initials: MC
authors.lastname: DeRosa
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics; D001483:Base Sequence; D015374:Biosensing Techniques; D005453:Fluorescence; D005506:Food Contamination; D008969:Molecular Sequence Data; D009793:Ochratoxins / Q000032:analysis*; D052156:SELEX Aptamer Technique
chemical_list: D052157:Aptamers, Nucleotide; D009793:Ochratoxins; C025589:ochratoxin A