In vitro selection of DNA aptamers and their integration in a competitive voltammetric biosensor for azlocillin determination in waste water

Raja Chinnappan, Shimaa Eissa, Atheer Alotaibi, Ayesha Siddiqua, Omar A. Alsager, Mohammed Zourob

Research output: Contribution to journalArticlepeer-review

31 Scopus citations

Abstract

The uncontrolled usage of veterinary antibiotics has led to their widespread pollution in waterways and milk products. Potential impact of antibiotic residues on the environment and human health such as increased antibiotic resistance of microorganisms and triggering allergic reactions in humans have been reported. In this work, we developed a highly selective and sensitive voltammetric aptasensor for on-step, sensitive and low cost detection of azlocillin antibiotic, one of the broad spectrum β-lactam antibiotics. The successful selection of DNA aptamers against azlocillin was accomplished using systemic evolution of ligands by exponential enrichment (SELEX) method. Fluorescence-binding assays showed dissociation constant of 55 nM for one of the selected aptamers (Az9). This aptamer was used to construct a competitive voltammetric aptasensor for azlocillin. A limit of detection of 1.2 pg/mL as well as remarkable selectivity against potential interfering agents, including amoxicillin, were achieved. This signal-off competitive sensor takes 30–50 min to complete the quantification of the target antibiotic. The sensor was challenged by detecting the target directly in complex environments such as tap and waste water where good recovery percentages were achieved.

Original languageBritish English
Pages (from-to)149-156
Number of pages8
JournalAnalytica Chimica Acta
Volume1101
DOIs
StatePublished - 8 Mar 2020

Keywords

  • Antibiotics
  • Aptamers
  • Azlocillin
  • Electrochemical sensor
  • Tap water
  • Waste water

Fingerprint

Dive into the research topics of 'In vitro selection of DNA aptamers and their integration in a competitive voltammetric biosensor for azlocillin determination in waste water'. Together they form a unique fingerprint.

Cite this