SERS Detection of Trace Carcinogenic Aromatic Amines Based on Amorphous MoO3 Monolayers
Xiangyu Meng1, Jian Yu1,2, Wenxiong Shi3
1School of Chemistry, Beihang University, Beijing, 100191, China.
Angewandte Chemie (International Ed. in English)
|May 31, 2024
Summary
Amorphous molybdenum trioxide (a-MoO3) monolayers enable sensitive detection of carcinogenic aromatic amines. This breakthrough utilizes a synergistic plasmon-induced hot-electron transfer and electromagnetic enhancement mechanism for rapid, accurate analysis.
Area of Science:
- Materials Science
- Nanotechnology
- Analytical Chemistry
Background:
- Carcinogenic aromatic amines pose significant health risks.
- Rapid and accurate detection methods are crucial for public safety.
- Existing detection techniques may lack sensitivity or speed.
Purpose of the Study:
- To develop a novel sensing platform for trace detection of aromatic amines.
- To investigate the underlying sensing mechanism involving amorphous molybdenum trioxide.
- To establish the efficacy of amorphous molybdenum trioxide monolayers in detecting carcinogenic compounds.
Main Methods:
- Fabrication of amorphous MoO3 (a-MoO3) monolayers exhibiting localized surface plasmon resonance (LSPR).
- Utilizing surface-enhanced Raman spectroscopy (SERS) for quantitative detection.
- Investigating plasmon-induced hot-electron transfer (PIHET) and electromagnetic enhancement (EM).
Main Results:
- a-MoO3 monolayers demonstrated a synergistic EM-PIHET enhancement mechanism.
- A significant decrease in hot-electron decay time was observed upon MO absorption, confirming PIHET.
- Achieved a low limit of detection (LOD) of 10^-9 M for o-aminoazotoluene (o-AAT).
- The a-MoO3 monolayers exhibited excellent uniformity, acid resistance, and thermal stability.
Conclusions:
- Amorphous MoO3 monolayers offer a highly sensitive and stable platform for detecting carcinogenic aromatic amines.
- The synergistic EM-PIHET mechanism is key to the enhanced SERS performance.
- This technology holds significant potential for reducing cancer infection rates through early detection.
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