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Counting Proteins in Single Cells with Addressable Droplet Microarrays
Published on: July 6, 2018
Quantification of protein based on single-molecule counting by total internal reflection fluorescence microscopy with
Lei Wang1, Guang Xu, Zhikun Shi
1School of Chemistry and Chemical Engineering, Shandong University, Jinan, PR China.
Analytica Chimica Acta
|April 10, 2007
Summary
This study introduces a sensitive single-molecule imaging technique for protein quantification using total internal reflection fluorescence microscopy. The method achieves adsorption equilibrium for accurate protein measurement, demonstrating a linear relationship with concentration.
Area of Science:
- Biophysics
- Analytical Chemistry
- Microscopy
Background:
- Accurate protein quantification is crucial in biological and chemical analyses.
- Existing methods may lack sensitivity or require complex sample preparation.
Purpose of the Study:
- To develop a sensitive single-molecule imaging method for protein quantification.
- To establish a reliable method using total internal reflection fluorescence microscopy and adsorption equilibrium.
Main Methods:
- Achieved adsorption equilibrium of proteins between solution and a glass substrate.
- Utilized total internal reflection fluorescence microscopy with an electron multiplying charge coupled device for imaging.
- Counted fluorescent spots corresponding to individual protein molecules.
Main Results:
- Demonstrated a sensitive single-molecule imaging method for protein quantification.
- Established an excellent linear relationship between the number of fluorescent spots and protein concentration.
- Determined a linear concentration range of 5.4 x 10(-11) to 8.1 x 10(-10) mol L(-1) using Alexa Fluor 488-labeled goat anti-rat IgG(H+L) as a model.
Conclusions:
- The developed method offers a sensitive and quantitative approach for protein analysis at the single-molecule level.
- This technique shows promise for applications requiring precise protein concentration measurements.
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