Simple, low-cost, sensitive and label-free aptasensor for the detection of cardiac troponin I based on a gold nanoparticles modified titanium foil

Biosens Bioelectron. 2019 Feb 1:126:381-388. doi: 10.1016/j.bios.2018.11.012. Epub 2018 Nov 13.

Abstract

This research demonstrated the electrochemical modification of low-cost titanium (Ti) metal substrate with gold nanoparticles (AuNPs) for the aptamer-based detection of cardiac troponin I (cTnI). AuNPs were deposited onto Ti sheets by the potential-step deposition method with high density and homogeneity as well as good crystallinity. It was then applied as a transducer to immobilize a thiol-functionalized DNA aptamer via the self-assembled monolayer mechanism for the specific binding of cTnI. This was verified through electrochemical and morphological analyses. The aptasensor could detect cTnI in a linear range of 1-1100 pM with a detection limit of ca. 0.18 pM. The aptasensor showed high sensitivity and specificity to cTnI over other interfering compounds with good recoveries in the diluted human serum samples.

Keywords: Aptamer; Cardiac troponin I; Differential pulse voltammetry; Gold nanoparticles; Label-free; Ti foil.

MeSH terms

  • Aptamers, Nucleotide / chemistry
  • Biosensing Techniques*
  • Electrochemical Techniques*
  • Gold / chemistry
  • Graphite / chemistry
  • Humans
  • Limit of Detection
  • Metal Nanoparticles / chemistry
  • Troponin I / blood
  • Troponin I / chemistry
  • Troponin I / isolation & purification*

Substances

  • Aptamers, Nucleotide
  • Troponin I
  • Gold
  • Graphite