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Electrowetting-based Digital Microfluidics Platform for Automated Enzyme-linked Immunosorbent Assay
Published on: February 23, 2020
A flow-through microarray cell for the online SERS detection of antibody-captured E. coli bacteria
Maria Knauer1, Natalia P Ivleva, Reinhard Niessner
1Institute of Hydrochemistry, Technische Universität München, Marchioninistrasse 17, 81377 Munich, Germany.
Analytical and Bioanalytical Chemistry
|September 28, 2011
Summary
We developed a novel flow-through microarray system for label-free bacteria detection using surface-enhanced Raman scattering (SERS). This automated method enables nondestructive, in situ analysis of microorganisms in water, with potential for drinking water monitoring.
Area of Science:
- Analytical Chemistry
- Microbiology
- Biotechnology
Background:
- Accurate and rapid detection of microorganisms in aqueous environments is crucial for public health and environmental monitoring.
- Existing methods for bacterial analysis can be time-consuming, labor-intensive, or require sample pre-treatment.
- There is a need for automated, nondestructive, and sensitive techniques for real-time microbial analysis.
Purpose of the Study:
- To develop and validate an automated immunoassay microarray flow-through system for the surface-enhanced Raman scattering (SERS) analysis of bacteria.
- To demonstrate the capability of the system for label-free, in situ imaging and quantification of microorganisms in aqueous samples.
- To assess the potential of the developed method for routine applications such as drinking water control.
Main Methods:
- Fabrication of a microarray chip with immobilized antibodies on a PEG-coated surface.
- Integration of the chip into a flow cell for automated sample introduction and analysis.
- Label-free detection of bacteria using surface-enhanced Raman scattering (SERS) after addition of colloidal metal nanoparticles.
- SERS mapping for quantification of microorganisms in water samples.
Main Results:
- Successful imaging of single microorganisms within the flow cell.
- Demonstration of SERS mapping for quantifying bacteria in water.
- Establishment of a linear detection range from 4.3 × 10^3 to 4.3 × 10^5 cells/mL.
- Validation of the system's capability for nondestructive, in situ analysis.
Conclusions:
- The developed immunoassay microarray flow-through system offers a sensitive and automated platform for SERS-based bacterial analysis.
- The system enables label-free detection and quantification of microorganisms in aqueous environments.
- This technology holds significant potential for routine applications, including real-time monitoring of drinking water quality.
