Rapid Electrochemical Detection of New Delhi Metallo-beta-lactamase Genes To Enable Point-of-Care Testing of Carbapenem-Resistant Enterobacteriaceae

Anal Chem. 2015 Aug 4;87(15):7738-45. doi: 10.1021/acs.analchem.5b01270. Epub 2015 Jul 14.

Abstract

The alarming rate at which antibiotic resistance is occurring in human pathogens causes a pressing need for improved diagnostic technologies aimed at rapid detection and point-of-care testing to support quick decision making regarding antibiotic therapy and patient management. Here, we report the successful development of an electrochemical biosensor to detect bla(NDM), the gene encoding the emerging New Delhi metallo-beta-lactamase, using label-free electrochemical impedance spectroscopy (EIS). The presence of this gene is of critical concern because organisms harboring bla(NDM) tend to be multiresistant, leaving very few treatment options. For the EIS assay, we used a bla(NDM)-specific PNA probe that was designed by applying a new approach that combines in silico probe design and fluorescence-based DNA microarray validation with electrochemical testing on gold screen-printed electrodes. The assay was successfully demonstrated for synthetic targets (LOD = 10 nM), PCR products (LOD = 100 pM), and direct, amplification-free detection from a bla(NDM)-harboring plasmid. The biosensor's specificity, preanalytical requirements, and performance under ambient conditions were demonstrated and successfully proved its suitability for further point-of-care test development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Typing Techniques / methods*
  • Carbapenems / pharmacology
  • Drug Resistance, Multiple, Bacterial / genetics
  • Electrochemical Techniques*
  • Enterobacteriaceae / classification
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae / genetics*
  • Enterobacteriaceae Infections / drug therapy
  • Enterobacteriaceae Infections / microbiology*
  • Humans
  • Protein Array Analysis
  • Time Factors
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • Carbapenems
  • beta-Lactamases
  • beta-lactamase NDM-1