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Published on: September 17, 2017
Rapid detection of microorganisms with nanoparticles and electron microscopy
Ghinwa Naja1, Sabahudin Hrapovic, Keith Male
1Department of Chemical Engineering, McGill University, 3610 University Street, H3A2B2 Montreal, Quebec, Canada. ghinwa.naja@mcgill.ca
Microscopy Research and Technique
|June 24, 2008
Summary
This study introduces a novel method for rapid microorganism detection using gold nanoparticles and scanning electron microscopy (SEM). The technique visually confirms the presence of bacteria like Escherichia coli and yeast like Candida sp.
Area of Science:
- Nanotechnology
- Microbiology
- Analytical Chemistry
Background:
- Rapid detection of microorganisms is crucial for various fields.
- Existing methods can be time-consuming or require specialized equipment.
- A need exists for a faster, more accessible detection technique.
Purpose of the Study:
- To develop a rapid procedure for microorganism detection.
- To utilize gold nanoparticles and scanning electron microscopy (SEM) for visualization.
- To confirm nanoparticle-cell interactions using ultraviolet resonance Raman spectroscopy (UVRS).
Main Methods:
- Interacting cell suspensions (Escherichia coli, Rhodococcus rhodochrous, Candida sp.) with gold nanoparticles (<10 nm).
- Eliminating salt interference via dialysis.
- Analyzing dried cell-nanoparticle suspensions using SEM.
- Confirming interactions with UVRS.
Main Results:
- Characteristic images of bacterial and yeast cells were observed under SEM.
- The presence of microorganisms in suspensions was visually confirmed.
- UV resonance Raman spectroscopy corroborated the SEM findings.
Conclusions:
- The developed procedure enables rapid and reliable detection of microorganisms.
- Gold nanoparticle-cell interactions visualized by SEM, confirmed by UVRS, offer a promising detection approach.
- This method holds potential for applications requiring swift microbial identification.
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