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Updated: Sep 7, 2025
Detection of Intracellular Gene Expression in Live Cells of Murine, Human and Porcine Origin Using Fluorescence-labeled Nanoparticles
Published on: November 13, 2015
Long-term continuous monitoring of microRNA in living cells using modified gold nanoprobe
Yuling Liang1, Huihui Yang1, Wen Yin1
1School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China.
Abstract:
Long-term and continuous monitoring of the microRNA (miRNA) expression in living cells is essential in biomedical research, but it is currently limited by fast consumption and easy digestion of probes in the intracellular environment. Herein, we report polydopamine-modified gold nanoparticles (AuNPs@PDA) as protective and efficient nanocarriers for DNA hairpin probes (hpDNA), achieving long-term monitoring (48 h) of the miRNA (let-7a) levels in living cells after drug treatments. This method enabled excellent sensitivity and high selectivity toward let-7a with a limit of detection of 0.51 nM (n = 3) and a linear range from 1 to 100 nM. More importantly, AuNPs@PDA can not only efficiently improve the loading of hpDNA on each nanoparticle, but also effectively protect hpDNA from hydrolysis in the cell microenvironment, finally realizing the continuous monitoring of let-7a in living cells for 48 h. This simple method would be of great significance for drug screening and precision medicine.
Insights
Researchers developed polydopamine-coated gold nanoparticles (AuNPs@PDA) to protect DNA probes for long-term microRNA monitoring in cells. This enables 48-hour tracking of let-7a levels, aiding drug screening and precision medicine.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Molecular Biology
Background:
- Long-term microRNA monitoring is crucial for biomedical research.
- Current methods are limited by probe degradation within cells.
Purpose of the Study:
- To develop a method for sustained intracellular microRNA detection.
- To enhance probe stability and monitoring duration in living cells.
Main Methods:
- Utilized polydopamine-modified gold nanoparticles (AuNPs@PDA) as nanocarriers for DNA hairpin probes (hpDNA).
- Implemented AuNPs@PDA for long-term monitoring of let-7a microRNA levels in living cells over 48 hours.
- Assessed sensitivity and selectivity of the developed system.
Main Results:
- Achieved sensitive and selective detection of let-7a with a limit of detection of 0.51 nM.
- Demonstrated effective protection of hpDNA from intracellular hydrolysis by AuNPs@PDA.
- Enabled continuous monitoring of let-7a levels for up to 48 hours in living cells.
Conclusions:
- AuNPs@PDA nanocarriers facilitate stable, long-term intracellular microRNA monitoring.
- This approach significantly improves upon existing limitations in probe stability and monitoring duration.
- The method holds promise for advancing drug screening and precision medicine applications.
