Simple Detection of the IS6110 Sequence of Mycobacterium tuberculosis Complex in Sputum, Based on PCR with Graphene Oxide

PLoS One. 2015 Aug 31;10(8):e0136954. doi: 10.1371/journal.pone.0136954. eCollection 2015.

Abstract

Graphene oxide (GO) has proven to be a satisfactory DNA-sensor platform for applications in enzyme-free signal amplification, fluorescence-based amplification, and nanoparticle-based platforms because of its excellent electrical, thermal, and optical properties. In this study, we designed a novel platform for the fluorescence detection of biomolecules, using a fluorescent dye-labeled primer and GO. We applied this system for the detection of the IS6110 insertion sequence of the Mycobacterium tuberculosis complex (MTB) and evaluated its feasibility for use in molecular diagnostics. Fifty-four sputum specimens were collected at our institution from October 2010 to March 2012. To detect MTB in the samples, we performed PCR amplification of the IS6110 DNA sequence using FAM-labeled primers, after which the PCR amplicon was incubated with GO and the fluorescence was measured. The results were compared with those obtained by conventional real-time quantitative PCR (RQ-PCR). The fluorescence intensity observed increased in a concentration-dependent manner with the FAM-labeled IS6110 amplicon. The results of the PCR-GO system for detecting IS6110 DNA were in good agreement with those obtained with conventional RQ-PCR (kappa statistic = 0.925). The PCR-GO system detected MTB DNA in 23 of 25 RQ-PCR-positive sputum samples (92.0%; 95% CI, 75.0-98.0%), but not in 29 of 29 RQ-PCR-negative sputum samples (100%; 95% CI, 88.1-100.0%). These results indicate the utility of the PCR-GO system in molecular diagnostics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Primers / genetics
  • DNA Transposable Elements / genetics*
  • DNA, Bacterial / genetics*
  • Fluorescence
  • Genes, Bacterial / genetics
  • Graphite / chemistry*
  • Humans
  • Mycobacterium tuberculosis / drug effects*
  • Nanoparticles / chemistry
  • Oxides / chemistry*
  • Real-Time Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity
  • Sputum / microbiology*
  • Tuberculosis, Pulmonary / microbiology

Substances

  • DNA Primers
  • DNA Transposable Elements
  • DNA, Bacterial
  • Oxides
  • Graphite

Grants and funding

This research was supported by the National Cancer Center, Grant NCC-1510100. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.