Two-color quantum dots-based fluorescence resonance energy transfer for rapid and sensitive detection of Salmonella on eggshells

In this paper, we report a novel strategy for highly sensitive, rapid, and selective detection of Salmonella Enteritidis using two-color quantum dots based on fluorescence resonance energy transfer (FRET) and fluoroimmunoassay technology. In this FRET system, two-color QDs were adopted as donors and acceptors simultaneously to improve its sensitivity and accuracy. The fluorescence intensity of QDs receptors decreased linearly with the increasing concentrations of S. Enteritidis from 75 to 5   ×   10 5   CFU/mL due to FRET system and fluoroimmunoassay reaction. The limit of detection of S. Enteritidis in this method was 10   CFU/mL without sample enrichment within 1–2   h. This method has been applied to the analysis S. Enteritidis of synthetic samples and eggshell samples. The QDs receptors even can potentially be developed into a sensor for quantitative or qualitative determination of S. Enteritidis in the further.