A rapid immunoassay method for the direct detection of PCR products: application to detection of TEM beta-lactamase genes

J Med Microbiol. 1996 Jul;45(1):76-8. doi: 10.1099/00222615-45-1-76.


A rapid immunoassay for the detection of specific PCR products is described in which a positive PCR amplification result is detected, usually in less than 5 min, by applying a few drops of the diluted PCR end-product to a small immunoassay sample device. The method was evaluated in comparison with conventional susceptibility tests and isoelectric focusing (IEF) for the detection of TEM-family beta-lactamase genes in 477 Escherichia coli isolates from urine samples. Of 187 isolates identified as presumptive TEM beta-lactamase producers by conventional methods, 185 generated a positive signal in the PCR immunoassay system. Two further signal-positive isolates were recognised when the PCR was repeated. In addition, one of the 276 ampicillin-susceptible isolates gave a positive signal in repeated PCR-immunoassay experiments despite being ampicillin susceptible and failing to give a TEM-type enzyme band in iso-electric focusing experiments.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteriuria / microbiology
  • Base Sequence
  • DNA Primers / chemistry
  • DNA, Bacterial / analysis*
  • DNA, Bacterial / chemistry
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Escherichia coli Infections / microbiology
  • Humans
  • Immunoassay / methods*
  • Isoelectric Focusing
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • RNA, Ribosomal, 16S / genetics
  • beta-Lactamases / genetics*


  • DNA Primers
  • DNA, Bacterial
  • RNA, Ribosomal, 16S
  • beta-Lactamases