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Resonance Raman Spectra for the In Situ Identification of Bacteria Strains and Their Inactivation Mechanism
Dinesh Dhankhar1, Anushka Nagpal1, Runze Li2
1Department of Electrical and Computer Engineering, Texas A&M University, College Station, USA.
Applied Spectroscopy
|February 19, 2021
Summary
Resonance Raman spectroscopy identifies bacterial strains and differentiates live from dead bacteria. This technique detects bacteria in water at low concentrations and can identify fungi, viruses, and plants in situ.
Area of Science:
- Biophotonics
- Spectroscopy
- Microbiology
Background:
- Bacterial carotenoids exhibit unique resonance Raman spectra.
- Spectroscopic methods are crucial for microbial identification and viability assessment.
- Current methods for detecting low bacterial concentrations are limited.
Purpose of the Study:
- To utilize resonance Raman spectroscopy for bacterial identification and viability.
- To develop a method for detecting bacteria in water at low concentrations.
- To explore the in situ application of this spectroscopic technique for various biological targets.
Main Methods:
- Recording resonance Raman spectra of bacterial carotenoids.
- Analyzing spectral intensity changes in response to ultraviolet (UV) radiation.
- Designing and employing a handheld spectrometer for in situ measurements.
- Quantifying bacterial detection limits in aqueous samples.
Main Results:
- Resonance Raman spectra successfully identified bacterial strains.
- Changes in spectral intensity differentiated live from dead bacteria.
- Bacteria were detected at concentrations as low as ~10^8 cells/mL.
- In situ measurements were feasible with the developed handheld spectrometer.
Conclusions:
- Resonance Raman spectroscopy is a viable tool for bacterial identification and viability assessment.
- The developed method offers enhanced sensitivity for bacterial detection in water.
- The technique shows potential for in situ identification of bacteria, fungi, viruses, and plants, and for rapid infection detection.
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