title: A novel electrochemical aptasensor based on Y-shape structure of dual-aptamer-complementary strand conjugate for ultrasensitive detection of myoglobin.
abstract: Monitoring of myoglobin (Mb) in human blood serum is highly in demand for early diagnosis of acute myocardial infarction (AMI). Here, a novel electrochemical aptasensor was developed for ultrasensitive and selective detection of Mb, based on Y-shape structure of dual-aptamer (DApt)-complementary strand of aptamer (CS) conjugate, gold electrode and exonuclease I (Exo I). The designed aptasensor obtains features of gold, such as high electrochemical conductivity and large surface area, property of Y-shape structure of DApt-CS conjugate to function as a gate and obstacle for the access of redox probe to the surface of electrode, as well as high specificity and sensitivity of aptamer toward its target and Exo I as an enzyme which specifically degrades the 3'-end of single-stranded DNA (ssDNA). In the absence of Mb, the Y-shape structure remains intact. So, a weak electrochemical signal is observed. Upon addition of target, the DApt leave the CS and bind to Mb, leading to disassembly of Y-shape structure and following the addition of Exo I, a strong electrochemical signal could be recorded. The fabricated aptasensor showed high selectivity toward Mb with a limit of detection (LOD) as low as 27 pM. Besides, the developed aptasensor was effectively applied to detect Mb in human serum.
authors.affiliation: Targeted Drug Delivery Research Center, 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, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran; Research Institute of Sciences and New Technology, Mashhad, Iran.
authors.forename: Noor Mohammad
authors.initials: NM
authors.lastname: Danesh
authors.affiliation: Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ramezani
authors.affiliation: Cardiovascular Research Center, Ghaem hospital, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: abnouskh@mums.ac.ir.
authors.forename: Ahmad Sarreshtehdar
authors.initials: AS
authors.lastname: Emrani
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: ahmad_sarreshtedar@yahoo.com.
authors.forename: Khalil
authors.initials: K
authors.lastname: Abnous
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques; D004277:DNA, Single-Stranded / Q000737:chemistry; D055664:Electrochemical Techniques; D005090:Exodeoxyribonucleases / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D009211:Myoglobin / Q000097:blood / Q000302:isolation & purification*; D009690:Nucleic Acid Conformation
chemical_list: D052157:Aptamers, Nucleotide; D004277:DNA, Single-Stranded; D009211:Myoglobin; D006046:Gold; D005090:Exodeoxyribonucleases; C028450:exodeoxyribonuclease I
keywords: Electrochemical aptasensor; Exonuclease I; Myoglobin; Y-shape structure