Paper strip whole cell biosensors: A portable test for the semiquantitative detection of bacterial quorum signaling molecules

Anjali Struss, Patrizia Pasini, C. Mark Ensor, Nilesh Raut, Sylvia Daunert

Research output: Contribution to journalArticlepeer-review

75 Scopus citations


Herein, we report the development of a novel, inexpensive, and portable filter-paper-based strip biosensor for the detection of bacterial quorum sensing signaling molecules, N-acylhomoserine lactones (AHLs). AHLs are generally employed by Gram-negative bacteria for their cell-cell communication to control expression of specialized genes, such as those involved in biofilm formation and production of virulence factors, in a population-density-dependent manner. First, a bacterial cell-based sensing system employing components of AHL-mediated QS regulatory system as recognition elements and β-galactosidase as the reporter protein was designed and developed. The bacterial-sensing cells were then liquid-dried on strips of filter paper. β-Galactosidase as the reporter allows for the visual monitoring of the analyte-induced signal when a colorimetric method of detection is applied. The paper strip biosensor was able to detect low AHL concentrations down to 1 × 10-8 M. Furthermore, it was successfully applied to the detection of AHLs in physiological samples, such as saliva. The filter-paper-based sensing strips could provide reproducible results upon storage at 4 C for at least 3 months. In conclusion, a filter-paper-based strip biosensor was developed that allows for visual, fast, and convenient detection of AHLs in a dose-dependent manner in a test sample. In addition, it does not require expensive equipment or trained personnel and allows ease of transportation and storage. Therefore, we envision that this biosensor will serve as a simple and economical portable field kit for on-site monitoring of AHL in a variety of clinical and environmental samples.

Original languageEnglish (US)
Pages (from-to)4457-4463
Number of pages7
JournalAnalytical Chemistry
Issue number11
StatePublished - Jun 1 2010
Externally publishedYes

ASJC Scopus subject areas

  • Analytical Chemistry


Dive into the research topics of 'Paper strip whole cell biosensors: A portable test for the semiquantitative detection of bacterial quorum signaling molecules'. Together they form a unique fingerprint.

Cite this