title: A novel colorimetric triple-helix molecular switch aptasensor for ultrasensitive detection of tetracycline.
abstract: Detection methods of antibiotic residues in blood serum and animal derived foods are of great interest. In this study a colorimetric aptasensor was designed for sensitive, selective and fast detection of tetracycline based on triple-helix molecular switch (THMS) and gold nanoparticles (AuNPs). As a biosensor, THMS shows distinct advantages including high stability, sensitivity and preserving the selectivity and affinity of the original aptamer. In the absence of tetracycline, THMS is stable, leading to the aggregation of AuNPs by salt and an obvious color change from red to blue. In the presence of tetracycline, aptamer binds to its target, signal transduction probe (STP) leaves the THMS and adsorbs on the surface of AuNPs. So the well-dispersed AuNPs remain stable against salt-induced aggregation with a red color. The presented aptasensor showed high selectivity toward tetracyclines with a limit of detection as low as 266 pM for tetracycline. The designed aptasensor was successfully applied to detect tetracycline in serum and milk.
authors: Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors: Mohammad
authors: M
authors: Ramezani
authors: Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran; Research Institute of Sciences and New Technology, Mashhad, Iran.
authors: Noor
authors: N
authors: Mohammad Danesh
authors: Academic Center For Education, Culture and Research (ACECR)-Mashhad Branch, Mashhad, Iran; Department of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran.
authors: Parirokh
authors: P
authors: Lavaee
authors: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: abnouskh@mums.ac.ir.
authors: Khalil
authors: K
authors: Abnous
authors: Targeted drug delivery Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: taghdisihm@mums.ac.ir.
authors: Seyed
authors: S
authors: Mohammad Taghdisi
mesh_terms: D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D003124:Colorimetry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005504:Food Analysis / Q000295:instrumentation*; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D008832:Microchemistry / Q000295:instrumentation; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013752:Tetracycline / Q000032:analysis* / Q000097:blood
chemical_list: D052157:Aptamers, Nucleotide; D013752:Tetracycline
keywords: Aptamer; Colorimetric biosensor; Gold nanoparticles; Tetracycline; Triple-helix molecular switch