基于无形MoO3单层的微量致癌芳香胺的SERS检测
Xiangyu Meng1, Jian Yu1,2, Wenxiong Shi3
1School of Chemistry, Beihang University, Beijing, 100191, China.
Angewandte Chemie (International ed. in English)
|May 31, 2024
概括
无形三氧化物 (a-MoO3) 单层使得可以灵敏地检测致癌性芳胺. 这一突破利用了由等离子体诱导的热电子转移和电磁增强机制的协同作用,用于快速,准确的分析.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 分析化学 分析化学
背景情况:
- 致癌性芳胺对健康构成重大风险.
- 快速准确的检测方法对于公共安全至关重要.
- 现有的检测技术可能缺乏灵敏度或速度.
研究的目的:
- 开发一种用于微量检测芳香胺的新型传感平台.
- 为了研究涉及无形三氧化物的潜在传感机制.
- 确定无形三氧化单层在检测致癌化合物的有效性.
主要方法:
- 无形MoO3 (a-MoO3) 单层的制造,表现出局部化的表面等离子体共振 (LSPR).
- 使用表面增强拉曼光谱法 (SERS) 进行定量检测.
- 研究等离子体诱导的热电子转移 (PIHET) 和电磁增强 (EM).
主要成果:
- a-MoO3单层显示出一个协同作用的EM-PIHET增强机制.
- 在MO吸收时观察到热电子衰变时间的显著减少,证实了PIHET.
- 对于o-aminoazotoluene (o-AAT) 的低检测极限 (LOD) 达到了 10^-9 M.
- a-MoO3单层表现出优异的均性,抗酸性和热稳定性.
结论:
- 无形MoO3单层为检测致癌芳胺提供了一个高度敏感和稳定的平台.
- 协同作用的EM-PIHET机制是提高SERS性能的关键.
- 这项技术具有显著的潜力,可以通过早期检测来降低癌症感染率.
相关概念视频
01:25Basicity of Heterocyclic Aromatic Amines
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
01:26Physical Properties of Amines
Amines with low molecular weight are usually gaseous at room temperature, while those with high molecular weight are liquid or solids in nature. Usually, low molecular weight amines have a rotten fish-like smell. Diamines typically have a pungent smell. For instance, cadaverine and putrescine, depicted in Figure 1, are two molecules responsible for decaying tissue.
01:14NMR Spectroscopy of Aromatic Compounds
Aromatic compounds can be identified or analyzed using proton NMR and carbon‐13 NMR. Typically, aromatic hydrogens or hydrogens directly bonded to the aromatic rings are strongly deshielded by the aromatic ring current. Therefore, they absorb in the range of 6.5–8.0 ppm in proton NMR spectra. For instance, aromatic hydrogens directly bonded to the benzene ring absorb at 7.3 ppm. However, aromatic hydrogens of larger rings absorb farther upfield or downfield than the ideal range. Consider...
01:19NMR Spectroscopy Of Amines
In proton NMR spectroscopy, primary amines and secondary amines showcase their N–H protons as a broad signal in the chemical shift range between δ 0.5 and 5 ppm. The exact position in this range depends on several factors, including sample concentration, hydrogen bonding, and the type of solvent used. Since amine protons undergo fast proton exchange in solution, the protons are labile and therefore do not participate in any splitting with adjacent protons. Thus, the observed peak is broad and...