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Synthesis of Near-Infrared Emitting Gold Nanoclusters for Biological Applications
Published on: March 22, 2020
Trypsin-stabilized fluorescent gold nanocluster for sensitive and selective Hg2+ detection
Hideya Kawasaki1, Kouta Yoshimura, Kenji Hamaguchi
1Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate, Suita, Osaka 564–8680, Japan. hkawa@kansai-u.ac.jp
Summary
Trypsin-stabilized gold nanoclusters (Au NCs) offer sensitive detection of mercury ions (Hg2+). These photostable fluorescent sensors provide selective mercury detection down to 50 nM.
Area of Science:
- Nanotechnology
- Analytical Chemistry
- Biochemistry
Background:
- Gold nanoclusters (Au NCs) are promising fluorescent materials.
- Mercury ions (Hg2+) pose significant environmental and health risks.
- Developing selective and sensitive Hg2+ detection methods is crucial.
Purpose of the Study:
- To develop trypsin-stabilized fluorescent gold nanoclusters (Au NCs) for Hg2+ detection.
- To evaluate the photostability and photochemical properties of these Au NCs.
- To assess the sensitivity and selectivity of the Au NCs as fluorescent sensors for Hg2+.
Main Methods:
- Synthesis of 1 nm sized gold nanoclusters stabilized by trypsin.
- Characterization of Au NCs' optical properties, including red emission at 645 nm.
- Investigation of photostability and photochemical stability compared to CdSe quantum dots.
- Evaluation of fluorescence quenching response to Hg2+ for detection limit determination.
Main Results:
- Trypsin-stabilized Au NCs exhibit red fluorescence at 645 nm.
- The Au NCs demonstrate photostability comparable to CdSe quantum dots.
- Fluorescence quenching by Hg2+ allows for sensitive and selective detection.
- A detection limit of 50 ± 10 nM and quantitative detection in the 50-600 nM range were achieved.
Conclusions:
- Trypsin-stabilized Au NCs are effective fluorescent sensors for Hg2+.
- The developed sensor offers high sensitivity, selectivity, and good photostability.
- This method provides a viable approach for detecting mercury ions in various samples.
