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Updated: Jun 25, 2026
09:57
Multiplex Chemical Imaging Based on Broadband Stimulated Raman Scattering Microscopy
Published on: July 25, 2022
Spectral analysis of multiplex Raman probe signatures
Barry R Lutz1, Claire E Dentinger, Lienchi N Nguyen
1Biomedical/Life Sciences, Digital Health Group, Intel Corporation, Santa Clara, California 95054, USA.
ACS Nano
|February 12, 2009
Summary
A new spectral fitting method enables quantitative analysis of multiplexed Raman nanoparticle probes. This approach overcomes limitations of conventional methods, allowing sensitive detection and accurate imaging in biological samples.
Area of Science:
- Biomedical Optics
- Nanotechnology
- Spectroscopy
Background:
- Raman nanoparticle probes offer unique spectral signatures for multiplexed bioassays.
- Conventional analysis methods are insufficient for fully realizing the potential of these probes.
- Accurate signal extraction from complex multiplex spectra is challenging.
Purpose of the Study:
- To develop and evaluate a novel spectral fitting method for quantitative analysis of multiplexed Raman nanoparticle probes.
- To demonstrate the method's effectiveness in various multiplex assay systems, including tissue imaging.
- To overcome limitations of existing analysis techniques for Raman probe applications.
Main Methods:
- A novel spectral fitting method was developed to quantitatively extract individual probe signals from multiplex spectra.
- The method was evaluated using composite organic-inorganic nanoparticles (COINs) in multiplex plate binding assays.
- Application in a triplex imaging assay on human prostate tissue using COINs and a conventional fluorophore.
Main Results:
- Sensitive multiplex detection of small signals (<2% of total signal) was achieved.
- Accurate and reproducible imaging of biomarkers in human prostate tissue with subcellular resolution.
- The spectral analysis error was consistently low (
- Effective removal of tissue autofluorescence and background noise.
Conclusions:
- The spectral fitting method enables robust quantification of multiplexed Raman probe signals with overlapping peaks.
- It facilitates automated, operator-independent background removal and error assessment.
- This approach significantly enhances the utility of Raman probes for quantitative in vivo and ex vivo multiplex analysis.
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