Early identification of pathogenic bacteria in food, water, and bodily fluids is very important and yet challenging, owing to sample complexities and large sample volumes that need to be rapidly screened. Existing screening methods based on plate counting or molecular analysis present various tradeoffs with regard to the detection time, accuracy/sensitivity, cost, and sample preparation complexity. Here, we present a computational live bacteria detection system that periodically captures coherent microscopy images of bacterial growth inside a 60-mm-diameter agar plate and analyses these time-lapsed holograms using deep neural networks for the rapid detection of bacterial growth and the classification of the corresponding species. The performance of our system was demonstrated by the rapid detection of
With the global rise of antimicrobial resistance, rapid screening and identification of low concentrations of microorganisms in less than 1 h becomes an urgent technological need for evidence‐based antibiotic therapy. Although many commercially available techniques are labeled for rapid microbial detection, they often require 24–48 h of cell enrichment to reach detectable levels. Here, it is shown that the widely used reducing agent tris(2‐carboxyethyl)phosphine (TCEP) can also act as a powerful oxidant on gold nanoplates and subsequently lead to a strong catalysis of luminol chemiluminescence. The catalytic reaction results in up to 100‐fold signal enhancement and unprecedented stable luminescence for up to 10 min. However, when TCEP is exposed to microorganisms, it is oxidized by the microbial surface proteins and loses its catalytic properties, leading to a decrease in chemiluminescence. The competitive interaction of TCEP with Au nanoplates and microorganisms is used to introduce a homogenous rapid detection method that allows microbial screening in less than 10 min with a limit of detection down to 100 cfu mL−1. Furthermore, the concept of microbial macromolecular shielding using antibody‐conjugated polymers is introduced. The combination of TCEP redox activity and macromolecular shielding enables specific microbial identification within 1 h, without preconcentration, cell enrichment, or heavy equipment other than a hand‐held luminometer. The technique is demonstrated by specific detection of methicillin‐resistant
- NSF-PAR ID:
- 10055768
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 7
- Issue:
- 13
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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