High-sensitivity bacterial detection using biotin-tagged phage and quantum-dot nanocomplexes.

Rotem Edgar; Michael McKinstry; Jeeseong Hwang; Amos B Oppenheim; Richard A Fekete; Gary Giulian; Carl Merril; Kunio Nagashima; Sankar Adhya

doi:10.1073/pnas.0601211103

PubMed · 16549760

High-sensitivity bacterial detection using biotin-tagged phage and quantum-dot nanocomplexes.

Rotem Edgar·Michael McKinstry·Jeeseong Hwang·Amos B Oppenheim·Richard A Fekete·Gary Giulian·Carl Merril·Kunio Nagashima·Sankar Adhya

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Abstract

With current concerns of antibiotic-resistant bacteria and biodefense, it has become important to rapidly identify infectious bacteria. Traditional technologies involving isolation and amplification of the pathogenic bacteria are time-consuming. We report a rapid and simple method that combines in vivo biotinylation of engineered host-specific bacteriophage and conjugation of the phage to streptavidin-coated quantum dots. The method provides specific detection of as few as 10 bacterial cells per milliliter in experimental samples, with an approximately 100-fold amplification of the signal over background in 1 h. We believe that the method can be applied to any bacteria susceptible to specific phages and would be particularly useful for detection of bacterial strains that are slow growing, e.g., Mycobacterium, or are highly infectious, e.g., Bacillus anthracis. The potential for simultaneous detection of different bacterial species in a single sample and applications in the study of phage biology are discussed.

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Bacteriophages Biotin Flow Cytometry Gram-Negative Bacteria Gram-Positive Bacteria Microscopy, Fluorescence Nanotechnology Quantum Dots Sensitivity and Specificity Time Factors Journal Article Research Support, N.I.H., Intramural Research Support, U.S. Gov't, Non-P.H.S.

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Rotem Edgar, Michael McKinstry, Jeeseong Hwang, Amos B Oppenheim, Richard A Fekete, Gary Giulian, Carl Merril, Kunio Nagashima, Sankar Adhya. 2006-03-20. High-sensitivity bacterial detection using biotin-tagged phage and quantum-dot nanocomplexes.. https://doi.org/10.1073/pnas.0601211103

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