title: Rapid identification of Salmonella using Hektoen enteric agar and 16s ribosomal DNA probe-gold nanoparticle immunochromatography assay in clinical faecal specimens.
abstract: A rapid identification of Salmonella, one of the most common foodborne pathogens worldwide, in clinical patients can enable better rational managements and prevent further outbreaks. The traditional immunochromatography using antibody-gold nanoparticles (Ab-AuNPs), such as the home pregnancy test, has been used for the Salmonella detection. In this study, we developed a new and rapid method using DNA probe-AuNPs for the detection of 16s ribosomal DNA of Salmonella. To evaluate the proposed method in clinical specimens, we performed a clinical test by identifying 159 stool samples on Hektoen agar containing black or crystalloid colonies using the method and the VITEK 2 system for confirmation. Eighty of the isolates were correctly identified as Salmonella to achieve 100% sensitivity. Seventy-five samples were correctly identified as non-Salmonella spp., but four were incorrectly identified as Salmonella. The specificity was 94·93%. The assay time is about 30 min after the DNA purification. The time-consuming and labour-intense biochemical tests can be replaced. We demonstrated that this assay is a rapid, convenient and cost-effective tool for Salmonella identification of clinical faecal samples, which is worth for further promotion and clinical use. This is the first application of using 16s ribosomal DNA probe-Au-NPs and immunochromatography on clinical samples.
  
  
  CONCLUSIONS
  This is the first application of using 16s ribosomal DNA probe-gold nanoparticles and immunochromatography method on clinical samples with sensitivity 100% and specificity 94·93%. The assay time is about 30 min after the DNA purification. We find this assay a rapid, convenient, sensitive and inexpensive tool for Salmonella identification of clinical faecal samples, which is worth further promotion and clinical use and can replace the traditional time-consuming and labour-intense biochemical tests. The potential benefit of this approach is to develop a rapid point-of-care test that provides results while the patient is still at the doctors' office.
authors.affiliation: Division of Gastroenterology and Nutrition, Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan; Institute of Biotechnology and Department of Chemical Engineering, National Taipei University of Technology, Taipei, Taiwan; Department on Nursing, Mackay College of Medicine, Nursing and Management, Taipei, Taiwan; Department of Medicine, Mackay Medical College, New Taipei City, Taiwan.
authors.forename: C-Y
authors.initials: CY
authors.lastname: Yeung
authors.forename: C-C
authors.initials: CC
authors.lastname: Liu
authors.forename: Y-T
authors.initials: YT
authors.lastname: Tseng
authors.forename: K-C
authors.initials: KC
authors.lastname: Tsai
authors.forename: M-A
authors.initials: MA
authors.lastname: Hsieh
authors.forename: W-T
authors.initials: WT
authors.lastname: Chan
authors.forename: H-L
authors.initials: HL
authors.lastname: Liu
authors.forename: H-C
authors.initials: HC
authors.lastname: Lee
authors.forename: S-Y
authors.initials: SY
authors.lastname: Hou
mesh_terms: D000362:Agar; D001483:Base Sequence; D002846:Chromatography, Affinity / Q000379:methods*; D015342:DNA Probes; D004275:DNA, Ribosomal; D005243:Feces / Q000382:microbiology*; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012475:Salmonella / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
chemical_list: D015342:DNA Probes; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D006046:Gold; D000362:Agar
keywords: Salmonella; gold nanoparticles; immunochromatography; lateral flow assay; molecular identification