Polymerase chain reaction-free, sample-to-answer bacterial detection in 30 minutes with integrated cell lysis

Anal Chem. 2012 Jan 3;84(1):21-5. doi: 10.1021/ac202599b. Epub 2011 Dec 13.

Abstract

An important goal for improved diagnosis and management of infectious disease is the development of rapid and accurate technologies for the decentralized detection of bacterial pathogens. Most current clinical methods that identify bacterial strains require time-consuming culture of the sample or procedures involving the polymerase chain reaction. Neither of these approaches has enabled testing at the point-of-need because of the requirement for skilled technicians and laboratory facilities. Here, we demonstrate the performance of an effective, integrated platform for the rapid detection of bacteria that combines a universal bacterial lysis approach and a sensitive nanostructured electrochemical biosensor. The lysis is rapid, is effective at releasing intercellular RNA from bacterial samples, and can be performed in a simple, cost-effective device integrated with an analysis chip. The platform was directly challenged with these unpurified lysates in buffer and urine. We successfully detected the presence of bacteria with high sensitivity and specificity and achieved a sample-to-answer turnaround time of 30 min. We have met the clinically relevant detection limit of 1 cfu/μL, indicating that uncultured samples can be analyzed. This advance will greatly reduce time to successful detection from days to minutes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Biosensing Techniques
  • DNA Primers
  • Electrochemistry
  • Escherichia coli / isolation & purification*
  • Flow Cytometry
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Reverse Transcriptase Polymerase Chain Reaction / methods*
  • Staphylococcus saprophyticus / isolation & purification*

Substances

  • DNA Primers