title: A novel fluorescent aptasensor for ultrasensitive detection of microcystin-LR based on single-walled carbon nanotubes and dapoxyl.
abstract: To assure water safety and protect human health, precise and simple analytical approaches are highly desired to determine low concentrations of microcystin-leucine-arginine (MC-LR), a toxin, in both water and serum samples. Herein, a simple, rapid and accurate aptamer-based fluorescent sensor was used for selective recognition of MC-LR, based on single-walled carbon nanotubes (SWNTs) as immobilizers, dapoxyl as a fluorescent dye, DAP-10 as a specific aptamer for dapoxyl and unmodified MC-LR aptamer (Apt) as a sensing ligand. The sensing method was developed to produce a remarkable fluorescence intensity difference in the absence and presence of MC-LR. Moreover, the Apt was used without any modification. In the absence of MC-LR, the dapoxyl could bind to DAP-10, leading to a strong fluorescence intensity. In the presence of MC-LR, DAP-10 bound to the surface of SWNTs, resulting in a very weak fluorescence intensity. Under optimized conditions, the presented fluorescent analytical approach showed high selectivity toward MC-LR with a limit of detection (LOD) of 138 pM. This new method indicated excellent analytical performance for MC-LR detection in tap water and serum samples with LODs of 135 and 168 pM, respectively.
authors.affiliation: Targeted Drug Delivery Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Pharmaceutical Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Seyed Mohammad
authors.initials: SM
authors.lastname: Taghdisi
authors.affiliation: Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Research Institute of Sciences and New Technology, Mashhad, Iran; Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Noor Mohammad
authors.initials: NM
authors.lastname: Danesh
authors.affiliation: Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ramezani
authors.affiliation: Department of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Narjes
authors.initials: N
authors.lastname: Ghows
authors.affiliation: Orthopedic Research Center, Mashhad University of Medical Sciences, Mashhad 9176699199, Iran.
authors.forename: Seyed Ali
authors.initials: SA
authors.lastname: Mousavi Shaegh
authors.affiliation: Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: abnouskh@mums.ac.ir.
authors.forename: Khalil
authors.initials: K
authors.lastname: Abnous
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D057230:Limit of Detection; D008387:Marine Toxins; D052998:Microcystins / Q000032:analysis* / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010080:Oxazoles / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D008387:Marine Toxins; D052998:Microcystins; D037742:Nanotubes, Carbon; D010080:Oxazoles; D013449:Sulfonamides; C412793:dapoxyl sulfonamide; C057862:cyanoginosin LR
keywords: Dapoxyl; Fluorescent aptasensor; Microcystin-LR; Single-walled carbon nanotubes